Amphibians of the Parque Natural Metropolitano, Panama A ... · Envr 451- Research in Panama . A....
Transcript of Amphibians of the Parque Natural Metropolitano, Panama A ... · Envr 451- Research in Panama . A....
Envr 451- Research in Panama April 25th, 2008
Amphibians of the Parque Natural Metropolitano, Panama
A study of amphibians and the development of an environmental education program
Guillaume Majeau-Bettez Adèle Michon
Louis-Philippe Potvin
Victor Thomasson
Presented to Dr Roberto Ibañez
McGill University
Under the Supervision of
Rafael Gómez and Amelia Muñoz
Parque Natural Metropolitano
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Executive Summary : Study of Amphibians of the Parque Natural Metropolitano By Guillaume Majeau-Bettez, Adèle Michon, Louis-Philippe Potvin, Victor Thomasson
Parque Natural Metropolitano, Ave. Juan Pablo II, Apartado 5499, Balboa, Ancón, Panamá, República de Panamá.
The Parque Natural Metropolitano (PNM) is definitely unique in many aspects. First of all, it is one of the only parks in the world that is found in the limits of a city. The Parque Natural Metropolitano is part of the Canal Zone protection corridor, along other major parks: Camino de Cruces and Soberania National Park. Due to the increasing pressure on land, it also represents one of the last refuges for dwellers of the Central-American dry tropical forest. Worldwide, the population of frogs is decreasing at an alarming rate. There is certainly fear to be felt from this change, since these creatures are considered to be indicators for environmental health. Because of their unique life traits, amphibians hold an extremely important ecological importance. They have been present on Earth for 360 millions of years, survived numerous mass extinctions periods, and so their decline should be taken very seriously. The objective of the project was to evaluate the diversity and the general state of the amphibians found in the park. Along with this, an identification guide of all possible frogs to encounter in the park was produced as a tool for visitors. In addition, an educational program on amphibians for school groups aged was designed to increase their interest for these creatures. The investigation was led during the dry season of Panama from February to April 2008. Seventeen transects of 3 meters wide by 100 meters long have been established in the PNM, and almost all transects were surveyed both during the day and during the night. Visual encounter surveys of transects were done by two investigators walking at a constant pace side by side, while moving the leaf litter with a stick. Eight wet transects, defined as transects with presence of at least a pond of water, and 9 dry transects, defined as forested areas without presence of water, were investigated in various areas of the park throughout the project. Full survey in wetter areas of a pool for a minimum of 15 minutes was done in five different regions through time-constrained surveys. The efforts spent in the field led us to encounter 14 different species of frogs. Among them, four had never been registered in the park’s directories. The latter are Hyalinobatrachium fleischmanni, Hypsiboas rosenbergi, Leptodactylus bolivianus, and Pristimantis taeniatus. A species curve analysis led us to believe that a total of 15 species could potentially inhabit the park, during dry season and using our methodology. In this sense, five of the species that are known to live in the park have not been encountered during our research. In terms of diversity, three species account for 90% of the individual encountered, whereas 11 species account for the remaining 10%. The density as well as the diversity of amphibians was significantly higher in humid areas. In conclusion, the amphibian diversity of the Parque Natural Metropolitano is quite high if we take into account its size and its proximity to anthropogenic disturbances. Our research effort shows that considerable time investment on the field may reveal the presence of species never encountered before. Amphibian diversity is not to be neglected at the PNM and thus, its
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conservation is crucial. It is recommended that there should be further research on amphibians at the park in order to monitor populations and evaluate the impact of increasing pollution.
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Resumen Ejecutivo : Estudio de los anfibios del Parque Natural Metropolitano
Por Guillaume Majeau-Bettez, Adèle Michon, Louis-Philippe Potvin, Victor Thomasson Parque Natural Metropolitano, Ave. Juan Pablo II, Apartado 5499, Balboa,
Ancón, Panamá, República de Panamá. El Parque Natural Metropolitano (PNM) es definitivamente único en muchos aspectos. En primer lugar, es uno de los únicos parques del mundo que se encuentra en los límites de una ciudad. El Parque Natural Metropolitano es parte del corredor protegido de la Zona del Canal, para la migración de varias especies entre dos otros parques importantes: Camino de Cruces y parque nacional Soberania. Debido a la presión creciente sobre la tierra, también representa uno de los refugios para los habitantes del bosque tropical seco centroamericano. Por todo el mundo, las poblaciones de anfibios están disminuyendo a un ritmo alarmante. Hay ciertamente miedo que se sentirá de este cambio, porque estas criaturas están consideradas como indicadores de la salud de los ecosistemas. Debido a sus rasgos distintivos de vida, los anfibios tienen una gran importancia ecológica. Han estado presentes en la tierra hace desde 360 millones de años, sobrevividos a numerosos períodos de extinciones, y entonces su declinación se debe tomar muy seriamente. El objetivo del proyecto era de evaluar la diversidad y el estado general de los anfibios encontrados en el parque. También, una guía de identificación de ranas y sapos del parque fue producida para los visitantes. Además, un programa educativo para grupos escolares de niños de 9 años sobre los anfibios fue diseñado para aumentar su interés sobre estas criaturas. La investigación fue realizada durante la estación seca de Panamá a partir de febrero hasta abril de 2008. Diecisiete transectos de 3 metros por 100 metros de largo se han establecido en el PNM, y casi todos fueron examinados por el día y la noche. Las investigaciones de encuentro visual de los transectos fueron hechas por dos investigadores que caminaban en un paso constante uno al lado del otro, mientras que movían la litera de la hoja con una ramita. Ocho transectos húmedos, definidos como transectos con presencia por lo menos de una charca del agua, y nueve transectos secos, definidos como áreas boscosas sin la presencia de agua, fueron investigados en varias áreas del parque a través del proyecto. Investigaciones completas en áreas más húmedas como estanques para un mínimo de 15 minutos fueron hechos en cinco áreas con exámenes específicamente por tiempo limitado. Nos esfuerzos en el campo nos llevaron a encontrar 14 especies de ranas. Entre ellas, cuatro nunca habían sido registrados en el parque. Estés último son Hyalinobatrachium fleischmanni, Hypsiboas rosenbergi, Leptodactylus bolivianus, y Pristimantis taeniatus. Una análisis con curva de especies nos llevó a creer que un total de 15 especies podrían potencialmente vivir en el parque, durante la estación seca y usando nuestro metodología. En este sentido, cinco de las especies que se sabe que viven en el parque no se han encontrado durante nuestra investigación. En términos de diversidad, tres especies valen por 90% de los individuos encontrados, mientras que 11 especies explican el 10%. La densidad así como la diversidad de anfibios eran perceptivamente más altas en áreas húmedas.
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En conclusión, la diversidad de anfibios del Parque Natural Metropolitano es muy alta si consideramos su tamaño y su proximidad a disturbios antropogénicos. Nuestro esfuerzo de investigación demuestra que la inversión de tiempo en el campo puede revelar la presencia de especies nunca encontradas antes. La diversidad de anfibios no debe ser descuidada en el PNM y su conservación es crucial. Se recomienda de hacer investigación adicional sobre los anfibios en el parque, para supervisar las poblaciones y evaluar el impacto de la contaminación cada vez mayor.
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Table of Contents Executive Summary : Study of Amphibians of the Parque Natural Metropolitano ...................................... 2
Resumen Ejecutivo : Estudio de los anfibios del Parque Natural Metropolitano ........................................ 4
1.0 Profile of host institution ................................................................................................................ 8
1.1 Coordinates ............................................................................................................................. 8
1.2 Main characteristics and brief history .......................................................................................... 8
1.3 Host Gratification .................................................................................................................... 10
2.0 Introduction ................................................................................................................................ 11
2.1 Natural History of Amphibians .................................................................................................. 11
2.2 Amphibians as Environmental Indicators................................................................................... 12
2.3 Visual Encounter Survey ......................................................................................................... 14
2.4 Species richness and species accumulation curves ................................................................... 15
2.5 Significance of subpopulation distinctions ................................................................................. 16
3.0 Goals, Objectives and Expected Results....................................................................................... 17
4.0 Methodology .............................................................................................................................. 18
5.0 Results ...................................................................................................................................... 21
5.1 Global Inventory ..................................................................................................................... 21
5.2 Species Richness ................................................................................................................... 23
5.3 Impact of water availability on amphibian populations ................................................................ 25
5.4 Spatial distributions within the park ........................................................................................... 27
6.0 Data Analysis ............................................................................................................................. 29
7.0 Discussion ................................................................................................................................. 31
8.0 Recommendations for further researches on amphibians in the PNM .............................................. 32
8.1 The sampling season .............................................................................................................. 32
8.2 The ANAM permit ................................................................................................................... 33
8.3 Other sampling methods ......................................................................................................... 33
8.3.1 Audio strip transects/calling survey .................................................................................... 33
8.3.2 Straight-line drift fences and pitfall traps ............................................................................. 33
8.4 GIS and remote sensing techniques ......................................................................................... 34
8.5 Areas to investigate ................................................................................................................ 34
8.6 Conservation issues................................................................................................................ 35
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8.6 GIS Map ................................................................................................................................ 35
8.7 Website ................................................................................................................................. 36
9.0 Acknowledgments ...................................................................................................................... 36
10.0 Cited Literature ......................................................................................................................... 37
Appendix I – Miscellaneous ............................................................................................................... 41
Annex 1. Chronogram of activities ..................................................................................................... 42
Annex 2: Schedule of Sampling ......................................................................................................... 43
Annex 3. Time spent on the project, divided between PNM and Panama .............................................. 44
Annex 4. Material and Budget ........................................................................................................... 45
Annex 5: Species list of the amphibians of the Parque Natural Metropolitano. ....................................... 46
Annex 6. Amphibian Monitoring - Transect Survey Sheet ................................................................... 47
Annex 7. Quantitative studies, capture-recapture, and amphibian marking techniques ........................... 48
Annex 8. Species richness and abundance distribution profiles for wet and dry transects ....................... 51
Annex 9. News Species encountered in the PNM ................................................................................ 53
Actividades educativas (version en español)....................................................................................... 56
Educational Activities (english version) ............................................................................................... 72
Identification Guide .......................................................................................................................... 87
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1.0 Profile of host institution
1.1 Coordinates Paque Natural Metropolitano Ave. Juan Pablo II Final Apdo. 0843-03129 Panamá, Rep. de Panamá Teléfono : 232-5552/232-5516 www.parquemetropolitano.org
1.2 Main characteristics and brief history The Parque Natural Metropolitano protects 232 hectars (1,159.43 m2) of natural area. Within the
watershed of the Panama Canal, it forms a chain with the Parque Nacional Camino de Cruces and the
Parque Nacional Soberanía. In such, it is a constituent of the Canal protection corridor, which conserves
an almost uninterrupted belt of forested land from the Atlantic coast all the way to the Pacific Ocean. This
protection corridor offers the important ecological service of regulating water runoffs in the Canal, along
with diminishing the erosion and sediment deposition in the Canal. The park protects one of the ultimate
representants of the dry pacific tropical forest in Central America.
However, it is its proximity to the city centre that makes this park so unique. It is the only park in all
Central America to be located within the limits of a metropolitan city. In thus, the park constitutes a bold
experiment attempting to demonstrate the cohabitation potential of wildlife and urban reality. The park is
under tremendous human pressure. During our internship alone, we witnessed proof of poaching and
dumped garbages from the road. The main portion of the park is cut from the Curundú River by the
Corredor Norte highway, which constitutes a major ecological problem since this river used to constitute an
important source of water for the fauna of this relatively dry park. In any case, some parts of the Curundú
River are polluted to a state of extreme desolation. Compensating for this diminished water access, a small
pond was dug and a network of artificial troughs were set-up in diverse regions of the park. The latter
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stopped working relatively shortly after its installation due to a technical problem with the pumping
apparatus (personal communication Mequizama). Nonetheless, some troughs were observed to still hold
significant amounts of rainwater even at the worst of the dry season.
The Parque Natural Metropolitano is the only important public park not run directly by the Autoritad
National del Ambiente (ANAM), but rather by a board of administrators from different spheres influence.
These include representants of local governments, the ANAM, nongovernmental organizations (NGO's)
and natural research institutions (e.g. Smithsonian Tropical Resarch Institute). The park was founded and
developed upon five operational mandates. First of all, it is entrusted to preserve the natural environment
of the park and contribute to a balance between urban activity and wildlife. Secondly, it is expected to
deliver recreational opportunities and services for the urban population of Panama. Thirdly, it should
facilitate environmental education. Also, it is part of the park's mandate to protect and clean the Curundú
River. Finally, the promotion and facilitation of scientific research within the park is one of its fundamental
priorities. (PNM 1999). Great effort is invested to achieve the first protection objective, notably through the
constant presence and patrol of forest guards in the park. The recreational offer of the park seems also
quite appropriate. Though Panamanians represent a minority of the visitors of the park (personal
communication), the park is still enjoyed by a great number of them and used for local events and local
company socialization activities. As far as environmental education is concerned (3rd objective), the park
works in partnership with local schools to give training to elementary teachers and organize field classes. It
is questionable whether the park has the financial means and tools necessary to effectively protect the
Curundú River. Finally, the present work is in direct agreement with the fifth objective of the park's
administration, which has facilitated our research to the best of their capacity.
Before the creation of the park, the land was administered by the Armed Forces of the
United-States of America. Many vestiges of the army's use of the land are still visible to this day (old rusted
military equipment, containers, storage building ruins, forest patterns indicating relatively young regrowth
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on former army campsite, vestige of trenches, etc.). Under presidential order, the first version of the park
was implemented in 1983, as the Area Recreativa de Curundú. It was shortly replaced legislatively in 1985
by the actual administrative structure under Ley No. 8. The Parque Natural Metropolitano was then
inogurated in 1988, to be fully operational in 1989.
Before the present investigation, the amphibian species registry of the park reported the presence
of one species of Gymnophiona and 13 species of Anura, encompassing four families: Oscaecilidae,
Bufonidae, Hylidae and Leptodactylidae (PNM 1999). A new species, Agalychnis spurelli, had been then
been inventoried in 2003 (Heffef et al. 2003).
1.3 Host Gratification The team that worked on the amphibians at the PNM requests that McGill sends a personal thanking letter
to the personal of the park.
• Amelia Muñoz • Rafael Gómez • Luis Peña • All park keepers that went with us in the park by night, but more specifically Sixto Mequizama
All of these people may be contacted at
Parque Natural Metropolitano Avenida Jean Pablo II, Final Apartado 5499, Balboa, Ancon
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2.0 Introduction
Since more than 25 years, studies show that amphibian populations in different parts of the world
are declining (Pechmann & Wilbur 1994). In the Monteverde Cloud Forest Reserve of Costa Rica, 18 of the
36 species of aquatic-breeding frogs would have disappeared after 1987 (Pounds et al. 1997). This study is
an example of how amphibian populations are declining even in pristine habitats. At a larger scale, 32.5%
of all described species of amphibians (5743 according to the IUCN Species Survival Commission) were
shown to be globally threatened. In addition, the percentage of amphibians on the brink of extinction (7.4%)
is higher than for birds (1.8%) or mammal (3.8%) (Stuart et al. 2004). Even though data are often missing,
the rate of extinction of amphibians is thought to be increasing. The IUCN – World Conservation Union
Global Amphibian Assessment (GAA) believes that 122 species of amphibians are possibly extinct, 113 of
which have probably disappeared since the 1980 (IUCN 2004). With the increase in human activity,
amphibian populations are also quickly declining. The population of 43.2% of all amphibian species has
decreased (Stuart et al. 2004). In this context, monitoring amphibian diversity and population sizes
becomes essential in order to assess changes in amphibian communities through time.
2.1 Natural History of Amphibians The first tetrapods to live on our planet were amphibians. They appeared when certain species of
lobe-finned fish gradually evolved limbs and became terrestrial. Ichthyostega is thought to have been the
first tetrapod and would have looked like a fish with four legs. It is believed that amphibians appeared in the
Late Devonian around 360 million years ago (University of Waikato 2007). Two morphologically distinct
forms of amphibians have emerged, but at different times. The labyrinthodonts appeared in the Late
Devonian, while the lepospondyls appeared in the Early Carboniferous (Heatwole and Carroll 1999). These
amphibians are now extinct but they are thought to have been the ancestors of modern amphibians (Carroll
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et al. 1999). Today, amphibians are defined as “any member of the class Amphibia, vertebrates
distinguished by their ability to exploit both aquatic and terrestrial habitats” (Encyclopædia Britannica 2007).
Class Amphibia encompasses three orders: Anura (frogs and toads), Caudata (salamanders and newts)
and Gymnophiona (caecilians). Frogs and toads are the most diverse group and can be characterized as
jumping amphibians that have no tail. Salamanders and newts have four legs and are found in a variety of
environments. Finally, caecilians are limbless, relatively long and are found in the tropical environments
worldwide (McDiarmid 1994).
Amphibians are found in an assortment of terrestrial and aquatic environments, from tropical
rainforest canopy to deserts. However, most species depend on water sources for reproduction. These
creatures are extremely important ecologically, as they consume large quantities of insects and provide
food to all sorts of different organisms (Ibáñez et al 1999). In a top-down perspective, they contribute to the
control of pest insect populations. They are also thought to play a role in the movement of nutrients
between aquatic and terrestrial systems (Ibáñez et al 1999). Finally, salamanders contribute to soil
dynamics by building burrows (David & Welsh 2004).
2.2 Amphibians as Environmental Indicators Anthropogenic activity is thought to be responsible for most of the problems that amphibians are
currently facing. Due to the decrease in stratospheric ozone, ambient levels of UV-B radiation have
increased significantly. This higher level of UV-B radiation is known to have a negative impact on
populations of amphibians (Blaustein and Wake 1995). It is thought to affect amphibians at all stages: the
embryo, the larval stage and after metamorphosis. Developmental abnormalities, embryo mortality and
reduced larval survival have been noticed in several species (AmphibiaWeb 2008). Chemical contaminants
also have various effects on amphibian communities and are partly responsible for this global amphibian
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crisis. Pesticides, heavy metals and fertilizers were all found to have an impact on amphibians. While
certain pesticides can alter their endocrine system and cause hermaphroditism, high levels of nitrate will
lead to developmental anomalies (Rouse et al. 1999; Hayes et al. 2002b; Hayes et al. 2003). With human
activity always increasing, many diseases are now resurging and spreading. For example, a chytrid fungus,
Batrachochytrium dendrobatidis, was found to decimate amphibian populations in Europe, Australia, New
Zealand and in the Americas (Berger et al. 1998). In western Panama, mass mortalities in amphibian
populations were associated to fungus infection (Lips 1999). The introduction of exotic species has also
changed amphibian populations. Introduced species of fish, such as bluegill sunfish and smallmouth bass
was found to be a serious menace to amphibian populations (Moyle and Light 1996). Finally, over-
exploitation and climate change have also played a role in the decline in amphibians throughout the world
(AmphibiaWeb 2008).
Because of their complex life history and unique anatomy, amphibians are believed to be great
environmental indicators. Most amphibians in larval stage require wet environment while adults will often
pass a considerable amount of time out of the water. Their permeable skins also absorb most chemical
contaminants (Duellman & Trued 1986). Finally, amphibians are ectothermal animals and rely on
behavioural adaptation to select particular microhabitats. For these reasons, the health of amphibian
communities strongly depends on the condition of their environment. By looking at amphibian
communities, we can infer on how healthy a certain environment is (Roy 2002). By allowing for a better
understanding of the current status of its amphibian community, the present study will constitute an
important indicator of the environmental state of the Parque Natural Metropolitano.
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2.3 Visual Encounter Survey Many monitoring techniques are applied on a standard basis for amphibian studies. Such
techniques include complete species inventory, visual encounter survey, audio strip transect, quadrat
sampling, drift fences and quantitative larvae sampling. Among these techniques, however, visual
encounter survey (VES) is the only method with low requirements in both cost and time investments
(Crump & Scott 1994). This technique is based on a search along a predetermined path through an area
of interest for a given period of time. Some VES surveys are time-constrained, while others are
spatially-constrained. Results are then expressed in terms of sightings per investigator-hour or per surface
area, respectively (Lips et al 2001). Visual encounter survey techniques assume that all individuals present
have the same chance of being observed, regardless of the species or the sampling session (e.g. no
seasonal variability). It is further assumed that individuals are encountered only once per survey session
and that observer-related effects are negligible.
Time-constrained visual encounter surveys constitute a suitable approach for the study of
populations confined to restricted areas, such as temporary ponds in the dry season. (Crump & Scott
1994). Since time is the only strict constraint, the investigation may be conducted in a variety of manners,
such as along a stream, a transect, or a random walk in a plot. While it can be used to determine species
richness and relative abundance of species in an area, this technique is not by itself an appropriate method
to measure population densities. The latter may be reasonably achieved, however, if time-constrained VES
is combined with mark-recapture (Donnelly 1989) (see Annex 7).
Spatially-constrained surveys — also referred to as transect sampling surveys — directly provide
population density and local species richness measurements, and do so across habitat gradients (Jaeger
1994). In addition to the basic assumptions presented above, density studies assume that the transect
sampling area is representative of the whole area studied. Consequently, transects should be randomly
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disseminated over the studied area. In this, spatially-constrained surveys differ greatly from
time-constrained ones, which are sometimes focused on areas of greater population abundance.
2.4 Species richness and species accumulation curves For conservation, ecological research, and macroecology, species richness is the most common
biodiversity indicator (Hortal et al. 2006). It is defined as the total number of species present in a given
area. Since the completeness of species inventories depends strongly on factors such as sample size,
sampling strategy, environmental parameters, species richness inventories are often difficult to compare.
In order to account for the effect of these different parameters and minimize their associated biases, a
number of extrapolation and rarefaction mathematical algorithms are available. All of them attempt to
account for species present yet not encountered in calculating total species richness. One numerical
methodology plots the number of encountered species as a function of sampling effort — defined in terms
of number of transects, hours of work, encountered specimens, etc. — producing a species accumulation
curve. The size of the “data cluster” defining a unit effort is often referred to as grain size, the smallest
possible grain size being an individual observation. The species accumulation curve is normally smoothed
free of any experimental fluctuation by averaging multiple equivalent versions of the curve, each one
calculated with the data (“effort units”) in a different randomized order. The species accumulation curve
can then be extrapolated asymptotically to an “infinite sampling effort”, thus accounting for probable non-
observations due to lack of sampling. Furthermore, species accumulation curves are routinely used to plan
sampling protocols effectively and to determine the pertinence of further investigation in a given are (Mao et
al 2005). Some other species richness estimators do not rely on asymptotic extrapolation, such as non-
parametric estimators and species-area curves. While the former interprets the species
abundance/occurence relationships within the sample with predetermined population criteria to estimate
total species richness, the latter achieves the same goal by using the relationships between species
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richness and sampled surfaces to extrapolate to the whole area of study (Hortal et al 2006). An ideal
species estimation model is (1) independent on sample size or sampling effort, (2) insensitive to sample
order or grouping, (3) insensitive to unevenness of species distribution (Chazdon et al 1998). Each of
model has its limitations however, and will be more appropriate for a certain type of population, sample
size, or grain size. Also, some models are more appropriate for abundance data (e.g. number of
individuals of a species per transect), while others are more appropriate for incidence data (e.g.
presence/absence of a species in a transect). Upon testing different grain and sample sizes, Hortal et al
(2006) concludes that smaller grain sizes “produce the most precise and unbiased estimations”. Certain
non-parametric estimators, such as ICE, Jackknife 1, Jackknife2, and Chao2, are reported to work
particularly well with such grain size, for incidence based data.
2.5 Significance of subpopulation distinctions Upon comparing sets of observations, it is routine work to estimate the probability that the null
hypothesis could explain the observations. In wildlife biology, this often means demonstrating that two
compared populations have little probability of actually corresponding to random internal variations within a
unique population. While the Student t-test is most often used for this sort of analysis, it is not always
possible due to violated assumptions. The t-test assumes normal distribution around the mean for the two
compared populations. Alternatively, in cases where the normality of the studied populations is doubtful,
some non-parametric tests should be applied. The Mann-Whitney U test can be used with fewer
assumptions to demonstrate that two samples are unlikely to originate from the same distribution. The
Mann-Whitney U test is based on the comparison of medians, does not assume Gaussian distribution, but
does assume that the distributions of the two populations are identical (Motulsky 1999).
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3.0 Goals, Objectives and Expected Results
In response to the park’s needs, the objectives of the present internship were to update the list of
amphibians living in the PNM and to create activities on environmental education and amphibian
conservation. This study therefore aimed at providing a clear description of the present status of the
amphibian community of the Parque Natural Metropolitano, Panamá.
It was hypothesized that the presence of species known to exist in the canal watershed but never
recorded in the park will be confirmed. This hypothesis was based on the assumption that the protection of
the park from anthropogenic disturbance will have allowed for an increase in amphibian biodiversity since
the census of 1999. Also, the year 2008 is characterized by La Niña climatic pattern, leading to more
humid conditions, and thus to better detection probabilities of amphibians. This research is expected to
broaden the current knowledge of amphibian species richness and population state in the park, and may
induce subsequent adjustments in specific area management.
The complementary part of the project aimed to initiate an educational program on amphibians,
with a focus on students from 8 to 9 years old. It was designed to teach them about the biology of
amphibians, their role in the environment, their fragility, and their importance as health indicators of
ecosystems. This part of the project will help the park to offer a program of discovery activities to
elementary schools, hence leading to better publicity, recognition, and access to funding. Also, as part of
the park objectives, the activity is expected to enable children to experience a profound contact with nature.
In turn, this should kindle their desire to learn more about amphibians and their habitats, and should
stimulate their early willingness to protect their environment.
A discovery pamphlet was also be designed for a broader public, detailing the species found in the
park and their dominant characteristics. It is expected to be a tool for people interested in knowing more
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about amphibians and their habitats. It should increase their general knowledge and appreciation of the
park as well as their willingness to protect their environment.
4.0 Methodology
After inspection of the different areas of the park, seventeen transects were established. Among
them, eight were located in “wet areas”, and nine in “dry areas” (see figure 1). In the present work,a wet
area is defined as any area with at least one pool of water larger than a small short-lived puddle. On the
other hand, dry transects were areas almost totally free of any surface water, with at most a small short-
lived puddle. While dry transects were consistently located in forests, a few wet transects were located in
more open areas. Dry transects were located rather randomly of the park, although their location was
highly dependant on density of the forest and ease of access. Transects were 3 meters wide and their
distance totalled 100 meters.
Five time-constrained pool surveys were also conducted in wet areas. The latter were natural or
artificially created pools of water. None of them completely dried out during the whole period of study,
although some lost significant volumes of water. During time-constrained pool surveys, pools of water were
entirely surveyed for a minimum of 15 minutes, with no limit of time, nor restriction on the number of
investigators. Strategically positioning the investigators around the pool made it possible for them to
search for amphibians to an approximate maximum distance of 3 meters from the water located on the
sides of the pool. Finally, the number of encountered individuals were reported as observations per hour
per investigator.
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Figure 1 Location of the different wet and dry transects on the Parque Nature Metropolitano, along with time-constrained pools
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Visual encounter surveys (VES) constituted the modus operandi of transect investigations. It
consisted in walking along the transect in pairs while looking for amphibians using a stick to move leafs
lying on the ground. Except for individuals whose identification was trivial and obvious, encountered
individuals were captured and photographed. Nets were used in order to reduce its chances of escaping.
It was later identified using the identification guide The Amphibians of Barro Colorado Monument,
Soberania National Park and Adjacent Areas by Roberto Ibañez (1999). Each time an individual was
captured, numerous pictures of several specific body parts were taken in a systematic manner. Dorsal,
lateral, ventral and frontal pictures of the captured individuals were routinely taken. As experimenters
walked the transect, a measuring tape was unrolled, and so each individual could be assigned a certain
distance at which it was found. The captured amphibians were rapidly released at their site of capture.
With only a few unfortunate exceptions, all transects and pools were investigated both during the
day and the night from February 22nd to April 11th 2008. The sampling hours for the morning shift started at
6h and never went beyond 11h. The night shifts started at 18h and usually ended around 23h.
Statistical treatment of the field data included the creation of a species accumulation curve, the use
of diverse non-parametric species richness estimators, among which ICE, Jackknife1, Jackknife2, and
Chao2 were retained. The distinct character of the populations in wet environments compared to dry
environments was quantified using theMann-Whitney U-test. All these tests and statistical tools were
provided by two free programs, EstimateS and Past.
The delay in obtaining the permit from the ANAM allowing us to mark amphibians made it
impossible to quantitatively evaluate the population of each species of the park through capture-recapture
(see Annex 7). The record of frog calls was not included in the methodology. Also, the specific
methodology did not focus on caecilians, and so records of caecilians were not expected. No identification
or record of larvae was performed. All research activities were performed in full awareness, understanding,
and respect of the McGill University Code of Ethics.
21
5.0 Results
5.1 Global Inventory The present results are based on the identification of 732 amphibians encountered during transect
and time-constrained surveys. In total, 14 species of amphibians were encountered, of which four species
were absent from the park's species inventory. Hence, the Hyalinobatrachium fleischmanni, the Hypsiboas
rosenbergi, the Leptodactylus bolivianus, and the Pristimantis taeniatus were added to the list of known
species present in the park. What is more, our inventory confirmed the continued presence of all but five of
the previously observed species (see Table 1). Of these, one is a caecilian (Oscaecilia ochrocephala) and
would have required significantly different investigation methodology. Similarly, experimental limitations are
most probably responsible for the non-observation of Craugastor crassidigitus, which resembles the
abundant Craugastor fitzingeri to the point of requiring physical capture for proper identification (vide infra).
22
Table 1 Species observations and abundance in the 2008 dry season investigation. These are compared to
previous inventories of the Parque Natural Metropolitano. Species with an asterisk constitute new species in the
park's inventory.
Agalychnis callidryas 3 — observed
Agalychnis spurrelli — observed —
Craugastor crassidigitus — observed observed
Craugastor fitzingeri 210 observed observed
Dendropsophus ebraccatus — — observed
Dendropsophus microcephalus 22 — observed
Dendropsophus phlebodes — — observed
Engystomops pustulosus 50 observed observed
Hyalinobatrachium fleischmanni* 4 — —
Hypsiboas rosenbergi* 10 — —
Leptodactylus bolivianus* 10 — —
Leptodactylus fragilis 4 — observed
Leptodactylus poecilochilus 2 — observed
Leptodactylus savagei 7 — observed
Oscaecilia ochrocephala — — observed
Pristimantis taeniatus* 1 — —
Rhinella alata 401 observed observed
Rhinella marina 5 observed observed
Smilisca sila 3 observed observed
Present InvestigationPFSS Internship
(2008)
Heffez et alPFSS Internship
(2003)
Management plan of the Parque Natural Metropolitano
(1999)
A better feel for the relative importance of each species is obtained if the abundance data in the
above table is reported as a pie graph, as in figure 2. The relative success of the two dominant species —
Rhinella alata and Craugastor fitzingeri, which respectively account for 54.8% and 28.7% of all encountered
amphibians — is incontrovertible.
23
Figure 2. Relative abundance of amphibian species in the Parque Natural Metropolitano, 2008 dry season survey
54.8%
28.7%
6.8%
3.0%4.0%1.4%1.4%
Rhinella alataCraugastor fitzingeriEngystomopspustulosusDendropsophusmicrocephalusOtherHypsiboas rosenbergiLeptodactylusbolivianus
5.2 Species Richness In order to estimate the total species richness of the Parque Natural Metropolitano, and also to
evaluate the appropriateness of our sampling effort, a randomized species accumulation curve was
produced. The smooth and thick curve in figure 3 represents the mean expected increase in observed
species as a function of the sampling effort. In accordance with the recommendations of Hortal et al
(2006), a small grain size was chosen for our data treatment. In fact, for the purpose of the species
accumulation curve, every encountered individual amphibian was treated as a separate sample, and hence
as an independent unit of sampling effort. This allowed us, among other things, to include observations
indiscriminately from both the transects and the time-constrained surveys in the total sampling experiment.
24
As a consequence of this choice of grain size, our species accumulation curve treatment corresponds to
that of an incidence data set (presence/absence), rather than that of an abundance data set.
0 100 200 300 400 500 600 7000
12
3
456
7
89
10
11
121314
15
1617
Singletons MeanChao 2 MeanICE MeanJackknife1Jackknife2Species AccumulationCurve (Sobs) (Mao Tau)
Number of encountered individuals
Numb
er of
Spe
cies
Figure 3. Species accumulation curve and species richness estimations for the Parque Natural
Metropolitano 2008 dry season inventory
The species accumulation curve on figure 3 displays a definite levelling out behaviour, hinting that the
investigation effort was appropriate. This was further confirmed and quantified by the use of four
non-parametric incidence-based species richness estimators, namely Chao2, Jackknife1, Jackknife2, and
ICE. As reported in Table 2, all these models estimated the total species richness to lie between 14 and 15
species, each with high levels of certainty. Hence, during the dry season and with the investigation
technique described in the methodology, one would not expect to encounter many additional species,
ceteris paribus.
25
Table 2. Summary of species accumulation curve and species richness estimates produced from the sum of all 732 individual samples (N = 732) by the program EstimateS
Numerical models Estimate
14.0 ± 1.4 (95% CI)ICE Mean* 14.4Chao2* 14.0Jackknife1* 15.0Jackknife2* 15.0 * NB. All Species Richness Estimations produced by the program EstimateS presented a null standard deviation for N>728
Species Accumulation Curve (Sobs)
5.3 Impact of water availability on amphibian populations In accordance with our hypothesis, this study demonstrated the importance of water bodies and
humid areas for the amphibian populations, especially during the dry season. As reported in table 3,
significant differences were noted in species richness, species relative abundance, and total amphibian
abundance. While all species but one were encountered at least once near water bodies, only half of the
species encountered (7) were ever located in “dry” forested regions of the park. Similarly, the mean
number of amphibians encountered in a “wet” transect is more than 8 times that of a “dry” transect, though
important standard deviations strongly diminish the significance of these averages. Also very tricking is the
change in the population profile. The two pie charts embedded in Table 3 clearly illustrate the diminished
relative importance of Rhinella alata in wetter areas, mostly to the relative benefit of Craugastor fitzingeri.
26
Table 3. Comparison of the amphibian populations of normal forested areas and wet areas of the Parque Natural Metropolitano during the dry season.
Normal Forested Areas Wet areas
Abundance (individuals per 100 m) (p = 0.0024)
5 (SD = 8)
40 (SD = 37)
Species incidence (p = 0.0385) 7 13
Species Relative Abundance (%)
74%
15%
5%5%
54%
31%
7%
9%
Rhinella alata Craugastor fitzingeri Engystomops pustulosus Others
NB. The Mann-Whitney U test was used to produce the p-values; the abbreviation SD. refers to the standard deviation from mean
The small p-values obtained when comparing observations in “wet” and “dry” regions of the park for
both amphibian abundance and species incidence — 0.0024 and 0.039, respectively — bring confidence
to the distinctions presented above. The probability that the observed species and population distributions
could be explained by random fluctuations within a single population thus fall bellow 4%. The p-values
were obtained using the Mann-Whitney U test, since this non-parametric statistical tool does not assume
normal distribution of either population, though it does assume that the two compared ensembles have
identical distribution profiles. As can be seen in Figure 5 of Annex 8, this latter condition is very well
respected for the species richness comparison, for which both samples present very similar profile shapes.
This less for the abundance comparison. Figures 6 and 7 of annex 8 present profiles without much
27
resemblance, and hence some bias may affect the p-value of the abundance comparison presented in
table 3 above.
5.4 Spatial distributions within the park Building onto figure 1 in the methodology section, figure 4 presents the labelled transects and
time-constrained pool surveys, with the total number of species and individuals observed on each of them.
This map may efficiently used to identify amphibian “hotspots”, as well as locations neglected by the
present study and appropriate for further investigation.
28
Figure. 4. Basic information on all transects and time-constrained pools : label name, species richness, number of encountered individuals. Labels with an asterisk (*) correspond to transects visited only once. All other results correspond to the sum of diurnal and nocturnal investigations. sp. = species ind. = individuals
29
6.0 Data Analysis
Many experimental parameters are suspected of either having cause a bias in the results or a limit
their precision. Typically, these fell into two main categories: an uneven sampling effort leading to samples
not fully representative of the parks environment or sampling techniques leading to uneven detectability of
different frog species. First, all data was collected between the months of January and April 2008, in the
middle of the dry season. In certain areas of the park, the leaf litter was particularly thick and it became
very hard to sample the ground. Amphibians are also highly dependant of water and many species will
decrease their level of activity when conditions are harsh. This can explain why the mean number of
amphibians encountered in a “wet” transect is more than 8 times that of a “dry” transect and why all species
except one were observed in wet areas but only half of the species were observed in wet areas. While
many species reproduce in wet season, only few species will do so in dry season. A majority of the
individuals encountered were in fact made of species that also reproduce in dry season (Rhinella alata
54.8% and Engystomops pustulosus 6.8%). Though most amphibian species are active at night, half of
samples were taken early in the morning when luminosity was relatively high. This is suspected to have
lead to an over-representation of diurnal species.
The areas sampled were also limited to the ones that were physically accessible. Most forest
present in the park is considered of secondary-growth and invasive bamboo species are dominating many
parts of the park. These areas were hard to sample and were therefore partly neglected.
Even tough a few species of new world caecilians are considered aquatic, most species are
thought to spend most of their life buried in the soil (Malonza & Measey 2005). Since the soil has not been
30
seriously investigated in this study, the only species ever recorded in the park could not have been
encountered during our investigation.
The transects sampled were also chosen with some preference for wet areas. The same number of
humid and dried transects were sampled, which does not reflect the ratio of wet and dry areas of the park.
This has probably lead to an over-representation of the species that are highly water dependant and a
diminished representation of species that are successful in drier conditions. The behaviour of certain
species also made them very hard to capture and observe. With its outstanding capacity to jump great
distances, Craugastor fitzingeri was the most difficult to capture. Other species were found deep in the leaf
litter, which made them difficultly detectable. Thirty minutes of intense search were required to uncover a
Leptodactylus poecilochilus calling deep in the humid leaf litter. Finally, searching for arboreal species was
challenging, especially at night. Not only was our vision limited, but no leaf or branches were investigated
over two meters of height.
Identification has also been a serious issue. Many members of the former genus Eleutherodactylus
are almost identical and it became necessary to carefully observe each individual in order to identify its
species. For example, one of the only characteristics that differentiate Craugastor fitzingeri from Craugastor
crassidigitus is the presence of small pale spots on its posterior surface of thigh(Ibáñez et al 1999).
Unfortunately it was impossible to capture all individuals, and it was difficult to systematically do so.
Species identification mistakes could have been done and it may explain the absence of Craugastor
crassidigitus in our registry.
Finally, all areas sampled are shown on the map of figure 1 and 4, but it does not represent their
exact location. The GPS used was unable to catch enough signals thus making it impossible to record
31
geographic points. The maps that were available were also imprecise and of poor quality. The ANAM even
had some GIS maps that disagreed on the location and shape of the park. The location of each transect
was therefore estimated using various approximated reference points.
7.0 Discussion
This study confirms the presence of 14 species of amphibians, four of which have never been
included in the registry of the park. Even though amphibian communities are dynamic, the authors believe
the reason why these four species had not yet been included in the registry of the park is because previous
research efforts were insufficient. The Parque Natural Metropolitano is more polluted today than ever
before and now receives thousands of visitors each year. It is therefore difficult to believe that the
amphibian diversity could have increased. Hence, the relative importance of Craugastor fitzingeri (210)
could be associated to the fact that the park is highly affected by anthropogenic activity and because this
species is though to be the most tolerant to disturbed habitats of its genus (AmphibiaWeb) . On the other
hand, the retreat of both military forces (American and Panamanian) could have allowed the expansion of
certain population. Old artificial structures such as the small “Castillo” are rapidly being recovered by
vegetation and become once again suitable environments for amphibians. A few frog species were seen in
high densities, breeding, at both the “Castillo” and at the troughs. As for the five amphibian species that
were not observed during this study but that had been seen in the past, it is difficult to say whether or not
they are extirpated. These species could very possibly be present in other areas of the park or be
significantly less active during the dry season. Only 5 years ago, in 2003, and during the same
investigation period, two species were observed that were not seen during this investigation. Further study
would be required to evaluate their current status in the park. The lack of extensive anterior studies also
makes the interpretation of our results very difficult, as we have no recent data to compare our data with.
Regular investigations would therefore be a key to evaluate the status and the dynamics of the amphibian
32
community of the park. Still, the data that we have obtained confirms the presence of different species in
specific areas of the park and gives a good indication of the status of several species. For example,
Agalychnis callidryas was observed in three different extremities of the park, while Smilisca sila and
Pristimantis taeniatus were observed in one area only of the park. Finally, we believe that the presence of
14 amphibian species (possibly 19 if none were extirpated) in the PNM is positive considering its proximity
to the city. Even though 55 species of amphibians are found in El Parque Nacional Soberania, El Parque
Natural Metropolitano is more than 70 times smaller (265ha vs. 19 341 ha), significantly drier, and
considerably more fragmented (Autoridad Nacional del Ambiente 2006). The relatively high amphibian
diversity of the park therefore makes it an ideal place to educate the public and to show the world that
conservation projects can be successful even in highly disturbed areas. Our data demonstrates the
importance of protection for the development and survival of biodiversity, especially in locations of intense
anthropogenic activity. Regular monitoring of amphibian populations, both qualitatively and quantitatively,
should hence be a priority for the park in the future, in order to assess the continued effectiveness of the
parks protection.
8.0 Recommendations for further researches on amphibians in the PNM
8.1 The sampling season Our survey has been conducted during the dry season. However, the vast majority of frogs and
toads encountered in the park reproduce during the rainy season. The probabilities of encountering
individuals are substantially higher if they are heard from their calls, research efforts should be
concentrated in this period of the year.
33
8.2 The ANAM permit It would be relevant to assess the abundance of the most commun species of the park, in order to
make a data comparison through time (every five or ten years). Monitoring the fluctuations in amphibian
populations would help in determining the impacts of the increasing pressure on their habitats. For this
matter, we recommend leading a capture-recapture investigation. However, this technique requires a
research permit from ANAM in order to have the authorization of marking individuals, and this may imply a
long administrative process. If a census is to be put forward, the next researchers should be aware that it
must imperatively be obtained early enough to start investigating , as field efforts will be considerable and
there no time can be lost if a good investigation is wanted.
8.3 Other sampling methods In order to be complementary to our research, alternative methods of sampling may be considered. In fact,
different methodologies will capture different species.
8.3.1 Audio strip transects/calling survey Audio strip transect would be particularly useful if an investigation is done during the rainy season. This
sampling technique allows to target a habitat (e.g. stream or pond) and to measure the relative
abundance of calling males, of adults, and the relative species composition. Also, it is a good
complement in the sense that it may record species living in higher strata of the forest, and which might
not have been counted using visual survey encounter techniques. Indeed, it gives equal weight to all
microhabitats of the forest, especially to the higher stratum and fossorial ones. Special attention should
be put on the recording equipment in order to achieve a highly reliable inventory.
8.3.2 Straight-line drift fences and pitfall traps The use of straight-line drift fences and of pitfall or funnel traps are to be considered for abundance
investigations. The latter are short barriers that direct animals traveling on the substrate surface into
traps placed at the end or on the side of the barrier. This could determine the species richness as well
34
as enable the detection of rare species of terrestrial amphibians, especially salamanders which have
hardly been recorded in the park yet. Furthermore, this technique could be conjointly used along with
the capture-recapture technique to assess species abundance at specific sites. There are several biases
to this technique and it is highly labour-intensive because one needs to go on the field on a daily basis,
yet it remains an option.
8.4 GIS and remote sensing techniques The use of cartography and databases for planning further researches is highly recommend for
further research. A powerful enough Global Positioning System (GPS) should be used to identify transects
and other on-site features, whereas the Geographic Information System (GIS) would be efficient in order to
produce high quality maps showing diversity hotspots.
8.5 Areas to investigate The researches performed in the park leaved various areas of interest not surveyed.
8.5.1 Northern section: Hence, forthcoming investigations should focus on sampling the northern section
of the park, where there is a potential for high species richness. This section is hardly perturbed, and the
formal through system left suitable areas for amphibian survival through the dry season. Also, the area
close to the national park Camino de las Cruzes should be further researched, since there is a potential
for species exchanges.
8.5.2 Canalized stream: A relevant sector to monitor would be the canalized stream running from the
workman’s hut through the ranch. This artificially wet area has been identified as having the highest
number of species.
8.5.3 El Castillo: The wet area near the Castillo has also been identified as an area of interest, from high
concentration of calling behaviour.
35
8.5.4 Forested areas: Furthermore, the discovery of a new arboreal species (Pristimantis taeniatus) in a
dry control transect (high forest near La cieneguita trail) reenforces the relevance of surveying areas that
may not be thought of as hotspots because of their lack of water.
8.6 Conservation issues Further researches should be done on the amphibian populations. Long term monitoring of
fluctuations should be considered as the amphibians are a good proxy to ecosystem health. The areas of
the park that remain wet during the dry season are crucial for amphibian survival. For this reason, the pump
of the formal trough system that has been constructed to counter the highway negative impacts on the
park’s hydrology should be operating again. Amphibians as well as all the fauna of the park would benefit
from this abandoned project. Preservation of the artificial concreted stream running from the workman’s hut
through the ranch seems essential since it is where the highest diversity has been encountered, and also
where three of the four new species have been found.
Furthermore, the Curundú River pollution is dramatically increasing, threatening the flora and fauna of the
park. Measures should be taken in order to stop the infernal pollution running through the Curundú River,
which was initiated by a pulp and paper and beer factory.
8.6 GIS Map
The administration of the park should meet with the ANAM in order to delimit official boundaries.
Different ones were found during our research, and it is a crucial tool in terms of use of space in
managing biodiversity.
36
8.7 Website
The Parque Natural Metropolitano website is well designed. However, regular updates are
essential to keep it optimally useful. Essential information is lacking, and many links are not working. First,
a map of the park trails should be included, as well as the map of directions to get there. Also, the picture of
the Dendrobate auratus should be removed, as this species and its family have never been found to live in
the park. Furthermore, a complete list of species inhabiting the park should be included (i.e different list for
mammals, birds and amphibians). This would work as an incentive for visitors to come and appreciate the
wonderful wildlife it has to offer. Finally, the product of our research should be available for the public on
the website, especially the list of amphibians, the identification guide and the research results.
9.0 Acknowledgments
We would like to thank our supervisors, Luis Peña, Amelia Muñoz y Rafael Gómez without which this
investigation would have not been possible. We would also like to express a special thanks to Sixto
Mequizama, as well as to all the people of El Parque Natural Metropolitano which have been of a great help
throughout our research. We are also grateful to Roberto Ibañez, who has helped us in the identification of
the amphibians encountered and responded to our countless emails. Our results could have also never
been analyzed without the statistical software EstimateS and Past; many thanks to their creators. We also
thank The Smithsonian Tropical Institute and McGill for the facilities, material and support they have
provided us. Finally, we are thankful to Ricardo Cossio who has allowed us to use his picture in the creation
of the guide to the amphibians of Panama.
37
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fluctuations and human impacts. Herpetologica 50:65-84.
40
Pounds, J.A., M.P.L. Fogden, J.M. Savage, and G.C. Gorman. 1997. Tests of null models for amphibian declines on a tropical mountain. Conservation Biology 11:1307-1322.
Robertson, J.G.M. 1984. A technique for individually marking frogs in behavioural studies. Herpetological
Review 15:56-57. Roy, D. 2002. Amphibians as environmental sentinels. Journal of Bioscience 27:187-188. Rouse, J. D., C. A. Bishop, and J. Struger. 1999. Nitrogen pollution: An assessment of its threat
to amphibian survival. Environmental Health Perspectives 107:799-803. Stille, W.T. 1950. The loss of jaw tags by toads. Chicago Academy of Science, Natural History Misc. 74:1-
2. Stuart, S., J.S. Chanson, N.A. Cox, B.E. Young, A.S.L. Rodriguez, D.L. Fishman, and R.W. Waller. 2004.
Status and trends of amphibian declines and extinctions worldwide. Science 306:1783-1786. University of Waikato. 2007. Plant and Animal Evolution [Online] Available at:
http://sci.waikato.ac.nz/evolution/AnimalEvolution.shtml#evolutionofamphibian [accessed 10 February 2008]
Wengert, G.M. and M.W. Gabriel. 2006. Using chin spot patterns to identify individual mountain yellow-
legged frogs. Northwestern Naturalist 87:192. Woodbury, A.M., Wm. E. Ricker, C. Cottam, R. D. Taber and R. C. Pendleton. 1956. Uses of marking
animals in ecological studies. Ecology 37:665-689.
Note: Bibliography was done following the standards of Journal of Herpetology
42
Annex 1. Chronogram of activities
Table 4 : Chronogram of activities
Dates Activity
Jan 4th Meeting with Luis and Amelia (Internship cocktail) Jan 5th First visit to park Jan10/Feb13 Park familiarization, literature review, permit forms Feb 13-14 Transects set up Feb 21 Beginning of sampling March 10-14 Internship week, sampling March 20 Informal presentation (premiliary data) March 20-21 No internship March 24-25 No internship April 7-11 Internship week, sampling April 11th End of sampling April 14-18 Data analysis and Final report writing April 23rd Symposium and Closing Ceremony April 25 Submission of final research reports
43
Annex 2: Schedule of Sampling
February 21st 5am - 10am 22nd 5am - 10am 27th 6pm - 10pm 29th 5am - 10am March 5th 6pm - 10pm 7th 5am - 10 am 10th 6pm - 10 pm 11th 5am -10am 6pm - 10 pm 12th 5am -10am 6pm - 10 pm 13th 5am -10am 6pm - 10 pm 14th 5am -10am April 7th 6pm - 10 pm 8th 5am -10am 6pm - 10 pm 9th 5am -10am 6pm - 10 pm 10th 5am -10am 6pm - 10 pm 11th 5am -10am
44
Annex 3. Time spent on the project, divided between PNM and Panama
Table 5 : Time spent on the project
Time spend working in the PNM
Time spend working in Panama
Total time spend on the project
January 24x3 = 72 h 8x4x3 = 96 h 168 h February 25x3 = 75 h 8x4x4 = 128 h 203 h March 40x2 = 80 h 10x4x4 = 160 h 240 h April 50x2 = 100 h 15x6x4 = 360 h 460 h Total of hours 327 hours 744 hours 1071 hours Days of work* 10.21 days 23.25 days 33.47 days
*Since we are a team of four, the number of hours have been summed up for the whole team, and then divided by 8 hours per day and per person.
45
Annex 4. Material and Budget
Table 6: Material and Budget
Material Quantity Cost
Walky-talky 2 Provided by PNM Camera 2 Provided by students
Frog Net 2 15$ Identification guide 2 Provided by students Working Gloves 3 5$ Machetes 2 Provided by students Flagging tape 3 3$ Measuring tape (20m) 2 Provided by students Ruler 2 Provided by students Transparent bags (Ziplok style) 500 10$ Thermometer 1 3$ Pluviometer 2 5$ Rubbing Alcohol and Antiseptic cream 1 10$
46
Annex 5: Species list of the amphibians of the Parque Natural Metropolitano.
Table 7: Actualized nomenclature of amphibians Formal Scientific Name Actualized Scientific Name English Common Name Spanish Common Name
Agalychnis callidryas Agalychnis callidryas Gaudy Leaf Frog Rana arbórea calzonuda Agalychnis spurrelli Agalychnis spurrelli Spurell's Flying Frog Rana voladora de Spurell Bufo marinus Rhinella marina Cane Toad Sapo Gigante Bufo typhonius Rhinella alata Leaflitter Toad Sapo Crestado Eleutherodactylus crassidigitus Craugastor crassidigitus Spot-shouldred Rain Frog Rana de lluvia de dedos anchos Eleutherodactylus fitzingeri Craugastor fitzingeri Common Rain Frog Rana de lluvia común Eleutherodactylus taeniatus Pristimantis taeniatus n.a. n.a. Hyalinobatrachium fleischmanni Hyalinobatrachium fleischmanni Fleischmasnn's Glass Frog Ranita de vidrio de Fleischmann Hyla ebraccata Dendropsophus ebraccatus Hourglass Treefrog Rana arbórea variegada Hyla microcephala Dendropsophus microcephalus Small-headed Treefrog Ranita arbórea grillo Hyla phlebodes Dendropsophus phlebodes Veined Treefrog Ranita arbórea venosa Hyla rosenbergi Hypsiboas rosenbergi Gladiator Frog Rana arbórea gladiatora Leptodactylus insularum Leptodactylus bolivianus Bolivian Frog Rana boliviana Leptodactylus labialis Leptodactylus fragilis White-lipped Whistling Frog Rana silbadora labiblanca Leptodactylus pentadactylus Leptodactylus savagei Smoky Jungle Frog Rana ternero / Sapo Toro Leptodactylus poecilochilus Leptodactylus poecilochilus Turbo white-lipped frog Rana de labios variados Oscaecilia ochrocephala Oscaecilia ochrocephala n.a. n.a. Physalaemus pustulosus Engystomops pustulosus Mud Puddle Frog Rana túngara Smilisca sila Smilisca sila Pug-nosed Smilisca Esmilisca nariz chata
47
Annex 6. Amphibian Monitoring - Transect Survey Sheet
Site: Transect name/number: Date: Dd/mm/yy
Starting time: Ending Time: No of observers: 1 2 3 4
Observer's names:
Weather
Sky: Cloudy Clear Fog Rain Air Temperature ºC Water Temperature ºC Relative humidity % Today's precipitations mm morning afternoon night Recent days dry light rain heavy rain flooding Moon tonight new 1st quarter full 3rd quarter No. Species Sex SVL Substrate Activity Time Comments 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
48
Annex 7. Quantitative studies, capture-recapture, and amphibian marking techniques
Capture-recapture Irrespective of the investigation method used, the probability of detecting amphibian specimens is
expected to differ depending on the season, the local environment and species of study. This makes
quantitative comparisons between population studies difficult (Mazerolle 2007). In order to account for
differences in detectability, the capture-recapture technique has been used frequently by herpetologists
since the 1920's (Woodbury 1956). With this methodology, a certain number of marked individuals are
released at their capture site and allowed to disseminate in the environment. This known subpopulation is
then used as a standard against which to evaluate the level of detection of the research. For example, if on
a given day half the marked individuals of a species are recaptured, it can be extrapolated that the
non-marked individuals captured represent half of the non-marked population. With multiple sampling
sequences, mark-recapture studies may also be used to evaluate demographic parameters such as death,
birth, and migration rates.
All mark-recapture models share two fundamental assumptions (Donnely & Guyer 1994). It is first
assumed that marked individuals are representative of the whole population, and that they remain so after
being marked. Should marked individuals present a bias in age or sex — or should the mark significantly
affect their behaviour, chance of recapture, or chance of survival — this primary assumption would be
considered violated. This assumption also implies that the released individuals must be given enough time
to randomly disseminate within their original population. It is further assumed that the marks are
permanent and remain intelligible throughout the study period. In addition to these two assumptions,
different mathematical models present secondary assumptions which vary depending on the number of
sampling events and the demographic parameters of interest. In the most basic population studies with
49
minimal numbers of sampling events, a closed population is generally assumed (i.e. no migration, no birth
and no death) (Donnely & Guyer 1994).
Marking techniques
Toe-clipping is the least expensive and most commonly used marking technique for anurans
(Donnelly & Guyer 1994; Ferner 2007). With the systematic removal of different combinations of toes,
thousands of individuals may be marked with the removal of no more than two toes (Donnelly 1989). Many
researches have been conducted with toe clipping without noting any significant impact on amphibian
survival and behaviour (Dole 1965; Halliday 1995; Dexter & Reaser 1996). Ferner (2007) concludes that
the sum of these publications has “far reaching” implications in favour of toe clipping. This technique
remains controversial, notably with publications from Clark (1972) and Daughtery (1976) reporting
significant negative impacts of toe clipping. McCarthy and Parris (2001) report that the return rate
diminishes by 4-11% for each toe removed, and that the impact of each toe removal increases linearly with
the number of toes removed. Frogs with two toes clipped present a return rate 96% of those with only one
clipped.
Other marking techniques found in the scientific literature for amphibians include the use of various
tags and waistbands, the injection of polymers or pigments, the implantation of passive integrated
transponders (PIT), radioactive tagging and branding (Ferner 2007). Jaw tagging was associated to
significant tag loss (Stille 1950) and considerable irritation (Woodbury 1956). Similarly, toe tags were
associated with pierced webbing of the foot (Kaplan 1958), and knee tags were found to cause frequent
lacerations (McAllister et al 2004). Waistbands, which must be both loose enough not to harm the subject
and snug enough not to catch in the vegetation, have also been associated with negative impacts on
amphibian survival (Robertson 1984) and should be removed after study period (Donnelly et al 1994). The
50
complexity and high cost of injection, implant, and branding techniques render them generally impractical
for small scale or low budget researches (Funk et al 2005). Funk et al (2005) also argue that little is known
on possible negative consequences of these marking techniques.
Pattern mapping constitutes a non-invasive alternative to marking for individual recognition in a
mark-recapture study. Using detailed photographs — lateral, dorsal, ventral and frontal — subjects have
been distinguished based on body marks (Kurashina et al 2003). Pattern mapping may prove especially
useful in situations where investigators do not hold the necessary permits to physically mark amphibian
subjects. However, comparisons of pictures for individual recognition can become very time consuming
when studying a large population of amphibians. Also, some species are known to present variation
through time in spot patterns, which renders this method less reliable for long term studies (Wengert &
Gabriel 2006).
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Annex 8. Species richness and abundance distribution profiles for wet and dry transects
The histograms bellow represent the distributions of the populations used for the Mann-Whitney U-test. The relative similarity or dissimilarity of their distribution profile shape can be visually evaluated, so as to evaluate the level of conformance to the Mann-Whitney assumptions.
Figure 5 : Histograms presentation of the species richness distribution
0 1 2 3 4 5 6 7 80
1
2
3
4
5
6
Dry TransectsWet Transects
Number of Encountered species
Num
ber o
f tra
nsec
tsco
rresp
ondi
ng t
o ob
serv
atiio
ns
52
Figure 6: Distribution of abundance data among dry transects. For transects visited twice, an average of the two surveys was used
0—2 2—4 4—6 6—8 8—10 10—12 12—14 14—16 16—18 18—20 20—22 22—240
1
2
3
4
5
6
Number of amphibians individuals per 100 m
Num
ber o
f Tra
nsec
tsco
rresp
ondin
g to
obs
erva
tion
Figure 7 Distribution of abundance data among wet transects. For transects visited twice, an average of the two surveys was used.
0—10 10—20 20—30 30—40 40—50 50—60 60—70 70—800
0.5
1
1.5
2
2.5
3
3.5
Number of encountered individuals
Num
ber o
f tran
sects
cor
resp
ondin
g to
obs
erva
tions
53
Annex 9. News Species encountered in the PNM
Figure 8. Hypsiboas rosenbergi
Figure 9: Hyalinobatrachium fleischmanni
56
APPENDIX Parte II : Programa de educación sobre los anfibios
Actividades educativas (version en español)
La parte complementaria del proyecto se dedica a recoger la información necesitada para la iniciación de un programa de educación sobre los anfibios. El programa se centra sobre los estudiantes de 8 o 9 años de edad. La intención es de enseñarlos sobre la biología de los anfibios, sus funciones en el medio ambiente, su estado frágil, y su importancia como indicadores de salud de los ecosistemas. Este parte del proyecto debe ayudar el parque a ofrecer un programa de actividades de descubrimiento para escuelas primarias, y así a mejorar su publicidad o su reconocimiento en la comunidad. También, los objetivos del parque incluyen de permitir a los niños de vivir una experiencia acercada de la naturaleza. Sucesivamente, estas actividades deberían aumentar sus deseo de aprender más sobre los anfibios y sus hábitats, y también estimular su voluntad de proteger el medio ambiente.
El proyecto de educación que presentamos está separado en bloques de actividades con los cuales los profesores podrán creer sus propios programas (Tabla 9). Estará del elección del profesor de enseñar la materia y de adaptar las actividades a las necesidades de los estudiantes y de manejar su tiempo.
La primera actividad de descubrimiento es una introducción al mundo de los anfibios. Inicia a los estudiantes a las divisiones del reino animal usando la llave taxonómica, así como explica las distinciones entre las subdivisiones importantes de los anfibios (i.e. ranas, sapos, salamandras y cecilias). El uso de un juego de asociaciones ayudará a los niños a entender la materia.
La segunda actividad explica las varias adaptaciones evolutivas de ranas y sapos a su ambiente, así como trae a la luz su anatomía y su metamorfosis. Pedirán a los niños identificar los órganos internos de una rana. Después, tendrán que colorear los etapas de vida de las ranas, y habrá una competencia en la cual el mejor dibuja será expuesto.
La tercera actividad es una lista de problemas matemáticos a resolver usando ejemplos de ranas. Se debe utilizar el conocimiento de la escuela de los estudiantes para enseñarles sobre la vida de los anfibios. La cuarta será centrada en el aprendizaje de las ranas y de los sapos del parque, incluyendo sus llamadas. La clase se continuará por una caminata hasta la laguna para intentar oír ranas y sapos.
La quinta actividad de descubrimiento se centrará en las adaptaciones de pies y de manos de los anfibios, y abarcará un juego de saltar “sistemáticamente” como las ranas. Para la actividad siguiente, los
57
niños tendrán que imitar comportamientos de ranas. Utilizarán sus creatividad juntada al conocimiento de las actividades anteriores para eso.
Para la séptima actividad, los niños aprenderán sobre la declinación mundial de los anfibios. Una corta caminata temática en el parque demostrará a los estudiantes que existe muchos tipos de amenazas, y que ellos mismos pueden ayudar a disminuirlas. Debe ayudar el estudiante a pensar en las varias mañeras que pueden ayudar para proteger los anfibios y sus hábitats.
La actividad ocho debe aprender a los niños cómo buscar para los anfibios, como los científicos verdaderos hacen sus investigaciones. Los sensibilizarán a la importancia de las medidas de seguridad en el campo, y les ensañara sobre los varios hábitats de ranas y sapos.
La novena actividad se concentra más sobre los mecanismos de defensa que los anfibios utilizan a contra de sus depredadores. El foco estará en las ranas veneno-de-dardo, los Dendrobates, que son famosas por sus colores brillantes y su uso humano ancestral de cuál tienen su nombre.
La última actividad sugerida es utilizar una rana como animal doméstico. Es un caso especial que requeriría una preparación anterior y pudo requerir un permiso del ANAM. Los niños serán enseñados a hacer como los científicos y buscar ranas en su propio patio.
La última actividad sugerida es utilizar una rana como animal doméstico. Éste es un caso especial que requeriría una preparación anterior y pudo requerir un permiso de ANAM. Los niños van a participar a la creación del acuario. Además, el parque ganaría de tener acuario para anfibios. Esto se podría incorporar en las actividades pues sería una gran oportunidad a los niños y el público en general de ver más cerca los animales que habitan el parque.
Tabla 9: Actividades educativas # Título de la actividad Contenido Afuera Duración 1 Introducción a los anfibios Taxonomía y subdivisiones de anfibios 1h 2 Adaptationes de los anfibios Cyclo de vida y organos 1h 3 Matemática de ranas Factos sobre ranas 30 min
4 Llamada de ranas Ranas y sapos del parque, identificación y llamados X 1h
5 La últimamima Facts on amphibians X 30 min 6 Ranas que saltan Adaptaciones de pies X 30 min
7 ¿Quién es responsable? Declinación de los anfibios y soluciones para contradecir amenazas X 1h
8 La rana perdida Investigación científica sobre los anfibios X 1h 9 Veneno mortal Presentacion oral del profesor 30 min 10 Nuestra Mascota La Rana Acuario para anfibios X 1h
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Título: 1. Introducción a los Anfibios Objetivos:
Familiarizar los niños al uso y a los principios básicos de las llaves taxonómicas Demonstrar las diferencias entre los anfibios y el resto del reino animal Diferenciar las subdivisiones principales de los anfibios (ranas, sapos, salamandras)
Lugar: Adentro
Duración: 1 hora
Números de participantes: 10-30, no limitación
Material: Un gran papel con la llave taxonómica Fotos de animales plastificadas
Consideración especial (de seguridad): Nada
Descripción: 1. En la primera parte de la actividad, el profesor muestra a los niños un animal familiar (gato,
perro, pollo, gusano) o de un anfibio (rana, sapo, salamandra). 2. Los niños deben contestar a una serie de preguntas sistemáticas de forma “sí o no” y
identificar el animal como correspondiendo a una rana, a un sapo, a un salamandra, o a un no-anfibio. Las preguntas y sus implicaciones serán visualmente accesibles en el papel pintado con la llave taxonómica. El profesor debe acentuar el mecanismo de la identificación deslizando la foto del animal plastificado al lado de las flechas de las llaves taxonómicas.
3. Después, el profesor demostrará las fotos de ranas, sapos, salamandras y cecilias, mientras que explicara a los niños las diferencias entre ellas.
Hechos relacionados: Los sapos tienen piernas más cortas y así que salte menos lejos que ranas. También tienen piel
seca mientras que las ranas tienen la piel mojada. Las salamandras tienen una cola. Cecilias son anfibios sin piernas que viven en la tierra. Se parecen a gusanos o a serpientes.
¡Pueden ser hasta 1,50m! ¿Las ranas tienen dientes? ¡Sí!! ¡Solamente en la quijada superior, así que ellas trague su presa
en la una sola pieza, glup!
Illustración: Un gran papel con la llave taxonomía
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Título: 2. Adaptaciones de las ranas Objetivos:
Enseñar a los niños la adaptación de ranas a su ambiente Explicar la metamorfosis que caracterice ellos Explicar la anatomía y la morfología de una rana Permitir que los niños se expresen dibujando Demostrar a los niños que las ranas son casi como nosotros
Lugar: Adentro
Duración: 1 hora
Números de participantes: 10-30, no limitación
Material: Lápices para colorar Fotocopias de nuestra plantillas Un libro simple de la biología para el
profesor
Consideración especial (de seguridad): Nada
Descripción: La clase entera mirará cada órgano y parte del cuerpo uno por uno. El profesor será
responsable de describir cada órgano y dirá a los niños cuáles son sus funciones. Los niños simplemente deberán llenar los espacios en blanco.
Después, el profesor hablara de la metamorfosis de los anfibios, y los niños tendrán que colorear la plantilla. El mejor dibujo será expuesto
Hechos relacionados: Metamorfosis de los anfibios:
• Los anfibios son caracterizados por su transformación del renacuajo al adulto. • Los huevos se ponen generalmente en el agua, muchas parecen espuma flotante. • Los renacuajos emergen de los huevos y de nadada en el agua. Tienen papadas, una cola y una
pequeña boca. • La metamorfosis comienza por las primeras piernas traseras, después las piernas delanteras, el
desarrollo del pulmón, la migración de ojos, la ampliación de la boca, y finalmente la resorción de la cola es la etapa pasada para las ranas.
Papel de cada órgano:
• Boca: Orificio a través del cual un organismo admite el alimento y el agua. • Cerebro: El centro de control del sistema nervioso. • Esófago: Tubo muscular a través del cual el alimento pasa de la faringe al estómago. • Pulmón: Transporte el oxígeno de la atmósfera en la circulación sanguínea, y lanzar el dióxido
de carbono. • Hígado: Varias funciones tales como secretar la bilis usada para la digestión. • Pequeño intestino: Absorción de las sustancias nutritivas • Intestino grande: Absorción del agua y colección de basura
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• Estómago: Degradacion del alimento • Páncreas: Glándula que tiene dos funciones, tiene características de las glándulas endocrinas y
exócrinas. • Corazón: órgano muscular que bombeo el sangre a través de los vasos sanguíneos. • Bazo: Destruye a los viejos glóbulos rojos y sostiene un depósito del sangre. • Vejiga urinaria: Almacene las orinas • Cloaca: Donde la esperma, los huevos, la orina, y las heces salen. • Ano: Donde las heces se expelen del cuerpo.
También
• Las ranas adultas son carnívoras, comen insectos, arañas, crustaceas, gusanos, sanguijuelas, así como caracoles y otros moluscos.
• Las ranas tienen una lengua adhesiva que se mueva de un tirón afuera para coger su presa. AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2008. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Apr 15, 2008).
Illustración: Hoja del estudiante, metamorfosis de rana:
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Título: 3. Matemática de ranas Objetivos:
Utilizar el conocimiento matemático de los estudiantes para aprender sobre las ranas
Lugar: Adentro
Duración: 30 min
Números de participantes: 10-30 no limitación
Material: Lápices y hoja de papeles Los problemas indicados en la hoja
Consideración especial (de seguridad): Nada
Descripción: Los niños ya deben tener el conocimiento sobre las ranas de las actividades anteriores. Para introducir la actividad, pregunte a los niños si saben como pequeño/grande son las ranas
del parque, o que comen ranas. El profesor puede escribir las preguntas en un tablero (si es disponible) o dar una hoja a cada
estudiante. Los niños pueden trabajar en solo o en pequeños grupos Las preguntas se hacen para ser de simple más difícil, y comprensivas.
Hechos relacionados: Referirse a las actividades anteriores
Ilustración: Problemas matemáticos Pregunta 1 Hay 11 ranas que llaman en una pequeña charca. Una serpiente viene y come 2 de ellos. ¿Cuánto la rana permanece? Respuesta: 11 - 2 = 9 ranas Pregunta 2 La rana más pequeña del parque es de medida 2.5 cm, es la Pristimantis taeniatus, mientras que la más grande, el Leptodactylus savagei, es 7.2 veces más grande. ¿Entonces, cuál es su tamaño? Respuesta: La Leptodactylus savagei mide 2.5 x 7.2 = 18 cm Pregunta 3 Las ranas deben hacer frente a muchas amenazas de los huevos al renacuajo al adulto. Diga que una madre rana pone 1000 huevos, y solamente la mitad de ellos sobrevive a la etapa del renacuajo. ¿Si de los renacuajo solamente ¼ se metamorfosean en adultos, cuántas ranas sobrevivieron? Respuesta: 800/2 = 400/4 = 100
Pregunta 4 Una rana Hyalinobatrachium fleischmanni puede comer 1 araña, 3 gusanos y 8 mosquitos en una noche. ¿Cuánto la presa él ha comido? ¿Y cuántos insectos este rana comería en 5 noches? Respuesta: 12 presas por noche
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Respuesta: 60 presas en cinco noches Pregunta 5 La rana Craugastor fitzingeri es una saltadora excepcional. Puede saltar tanto como 1.5 m de largo y puede saltar 5 veces en una fila. ¿Hasta dónde puede ir? Respuesta: 1,5m x 6 = 9 m Pregunta 6 Durante la estación seca, la rana Engystomops pustulosus emigra por las charcas, que recogieron el agua a partir de la estación lluviosa. ¿Si una charca de 20cm2 puede sostener 6 ranas, cuántas ranas pueden sobrevivir en una charca de 1m2? Respuesta: 5 x 6 = 30 ranas Pregunta 7 Una rana está buscando a su amigo que se esta sentando en el otro lado de un gran tronco. El registro mide 40cm por 30cm. La rana está vagando cuál sería la distancia si él utiliza sus piernas largas para saltar sobre el tronco. Ayúdele a determinarla. Respuesta: √402 + 302 = 50
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Título: 4. Llamadas de ranas Objetivos:
Familiarizar los niños con la diversidad de ranas y de sapos, así como a sus llamadas
Lugar: Interior y exterior
Duración: 1 hora
Números de participantes: 10 a 30, ninguna restricción
Material: CD de llamadas de ranas y sapos Fotos de ranas y sapos
Consideración especial (de seguridad): - Cuando al lado de la laguna, los niños deban
estar bajo la supervisión del profesor - Las serpientes son un asunto importante - Siempre mire delante de usted cuando camina- Nunca pone su mano en alguna parte que no
puede ver - Los profesores deben asegurarse en que la
trayectoria es seguro
Descripción:
Para presentar la actividad a los niños, pregúntele de imitar lo que piensan son las llamadas de ranas.
Después, como iniciación a las llamadas, juegue las que viven en el parque y, al mismo tiempo, demuestre sus fotos y dice las características importantes (eg. rana arbórea, nocturnas,…) cuáles serían escritos detrás de las fotos.
Después de esta iniciación, juegue con los niños, dividiendo la clase en equipos de dos. La meta del juego es de identificar la especie de la rana por su llamada. El equipo que gana es el que recoge más puntos.
El profesor pone las fotos para que los niños pueden verlos. Juegue la llamada de una rana y el niño del primer equipo debe buscar cuál es la buena foto. Si el niño no sabe, él podría pedir una por una indirecta (una de las características) pero vale solo medio punto. Si el niño da una respuesta incorrecta, la vuelta va al otro equipo. Para animar el espirativo de equipo, los niños tienen que coger un nombre de la rana.
La segunda parte de la actividad es una caminata para oír las llamadas de ranas y sapos. Pedirán a los niños de caminar reservado para oído bien. Una parada a la laguna será hecha porque es el lugar más seguro por los niños, y el más probable de oír llamas. Ni se espera de los niños ni del profesor se recuerden todas las llamadas de las especies, los niños voluntarios serán pedidos de imitar las llamadas para identificarlas cuando regresaran a la clase.
Hechos relacionados: La llamada de ranas se llama “croar” y es diferente para cada especie. El sonido es hecho por
el varón y la hembra, pasando a través de sus cuerdas vocales (laringe) en su garganta. Los varones también tienen sacos vocales permitiendo que croen más ruidosamente que las hembras. Esos sacos son membranas de piel situados debajo de la garganta o al lado de la boca, y que expenden para amplificar la llamada. Algunas ranas no tienen saco vocal.
Las ranas llaman principalmente en la estación de la reproducción para atraer a compañeros,
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pero también para comunicar en otra situación de vida. Muchas especies también tienen llamadas específicas para defender su territorio, antes de la lluvia o llamadas de socorro. Un ciertas especies se llaman de su llamada, como la rana falsa-grillo en los E.E.U.U.
Ilustración: Debe incluir las fotos de ranas, con las características estrito detrás. Debe incluir el CD de llamadas de ranas y sapos.
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Título: 5. El último sapo-mimo! Objetivos:
Compartir el conocimiento y las perspectivas sobre los anfibios Hace una actividad dinámica en cuales los niños pueden expresarse Developer las habilidades artísticas y la creatividad de los niños con el lenguaje del cuerpo
Lugar: Interior y exterior
Duración: 30 min.
Números de participantes: 10-30, no limitación
Material: Algunas lápices y papel
Consideración especial (de seguridad): Nada
Descripción: Cada niño debe escribir sobre un trozo de papel algo que sus compañeros deberán expresar con
mímicas, que esta relacionado a los anfibios (ej. Saltar, comer, dormir, nadar, escalar..) Después, doblar los papeles y mezclarlos en un sobrero o otro Sentar los niños para formar un circulo, para que todos pueden ver las hazañas Uno después del otro, los niños escogerán un mime del sombrero y realizarán el mime Sus compañeros de clase tendrán que conjeturar lo que mima el ejecutante Después de cada hazañas, el profesor debe agregar algunos comentarios sobre cómo es en la
naturaleza
Hechos relacionados: IDEAS Muchos anfibios pueden comer casi cualquiera presa si sea bastante pequeña para caber en su
boca! Muchos anfibios cogen sus presas con su boca y pinzas pero utilizan sus piernas delanteras
para rellenar su garganta. Mientras que algunas ranas pueden saltar sobre distancia grande otra puede hacer solamente
pequeños saltos. Las cecilias se mueven como serpiente Algunas ranas arborícolas se mueven casi como monos. La metamorfosis de la mayoría de los anfibios tiene un mínimo de de tres fases: huevo,
renacuajo, adulto. Para conservar su humedad, los anfibios se cerrarán los ojos y traerán sus piernas firmemente a
su cuerpo. Para evitar la depredación, algunas ranas se hinchan como una bola o extienden sus piernas y
caminan como un perro.
Ilustración:
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Titulo: 6. Ranas Saltan! Objetivos:
Explicar las adaptaciones de las piernas de ranas a sus ambientes Dar a los niños un sentido de la importancia del salto para el sobreviviendo de las ranas a contra de los predadores. Dar a los niños la oportunidad de hacer ejercicio físico al exterior Developer las habilidades de competición y cooperación con el espirativo de equipo
Lugar: Interior y exterior
Duración: 1 hora
Números de participantes: 10-30, no limitación
Material: Cinta métrica de 30 metros Algunas marcas por las distancias Una cuerda para marcar el punto de partida
Consideración especial (de seguridad) Nada
Descripción: El profesor explicara la varias evoluciones de los manos y pies con sus ambientes Después de la classe, un juego siguiera. Los niño s esperan al punto de partida y, uno despues
del otro, saltaran para saber quien puede saltar mas lejos. Las distencias seran grabadas. El profesor debe decir a los niño s que las ranas pueden saltar 20 veces sus tamanos, y
entonces, los niño s podrian saltar mas de 20 metros en un solo salto! Con los niño s, el profesor medira 20m desde el punto de partida. Eso es la distancia que los
niño s habrian podido si estarian ranas! Que prático para escapar de sus predadores! Actividad de cooperacion: Los niño s deben completar un distancia de 20 metro, juntos. El
primero niño salta, como un metro y desde este punto el niño siguiente salta, para llegar a hacer los 20 metros. Cuantos niño s deben trabajar juntos para saltar un solo salto de tamano-humano-rana.
Hechos relacionados: La capacidad de saltar es una distinction importante entre los anfibios. Las ranas pueden saltar
muy lejos, pero los sapos solo pequenas distancias. Las salamandras y las cecilias no pueden saltar.
La rana-chapulín, Acris crepitans, es la mejora saltadora de todas las ranas porque puede saltar hasta 36 veces su tamaño! (http://www.kiddyhouse.com/Themes/frogs/)
En términos de distancia, el salto mas lejo fui en Africa Del Sur, en partidos con equipos locales, y el salto media 10,19 m (allaboutfrogs.org)
Adaptaciones de piernas La estructura de las patas de ranas evolucionaron con su ambiente y su estilo de vida (vida en
árboles, en la agua..) Los piernas con membranas pálidas para nadar Discos de succión sobre los dedos para trepar a los arboles Extra-grande membranas pálidas para saltar en el aire, como volar Espinas sobre los pies de los machos para agarrar las hambras durante la reproduccion Los saltadores especialistes como las Hylidaes tienen piernas especiales para mejor saltos.
Ilustración:
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Título: 7. ¿Quién está responsable? Objetivos:
Ensenar a los niños el declive de los anfibios y sus causas Mostrar a los niños que es importante de proteger su medio ambiente Tomar el tiempo de estar afuera y deshacerse de las basuras
Lugar: Al exterior
Duración: 1 hora
Números de participantes: 10-30, no limitación
Material: Pantalones Zapata Poner su calcetín sobre los pantalones
Consideración especial (de seguridad): - Hay serpientes en el parque, es un tema muy
serio. - Siempre debe mirar en frente cuando camina - Nunca pone tu mano en un sitio que no puede
mirar bien! - Entonces el maestro siempre debe caminar al
frente de los niños.
Descripción: El profesor debería empezar la actividad con una clase sobre el declive de los anfibios. Se
debería explicar porque las poblaciones de anfibios están disminuyendo en todo el mundo. Las causas deberían estar indicada claramente.
Con el profesor, el niño caminara en la selva. Toda la clase buscara por objetos o cualquiera fuente de polución que podría tener un impacto
negativo sobre los anfibios. El profesor hacera comentarios sobre lo que encontraran. Estará una buena oportunidad de limpiar el parque.
Hechos relacionados: Más que 6300 especies de anfibios viven en el mundo. Desafortunadamente, 1/3 de estas
especies están en peligroso. Aunque los anfibios viven sobre la planeta por mas de 300 millones de anos, en solo 20 anos
se ha perdido 168 especies y la tasa de extinción esta creciendo. Las especies más amenazadas se encuentran en America Central, Asia e Indonesia. Las causas del declive están muy diversas, como la destrucción de los hábitats, las especies introducidas, los cambios climáticos, la explotación excesiva, contaminantes químicos y enfermedad (patógeno fungicida).
En Panamá, el hongo patógeno B. dendrobatidis es un problema serio. Es la causa principal del declive de la famosa Rana Dorada. Ese hongo tiene un impacto negativo sobre las poblaciones de anfibios del mundo, especialmente en Australia, Central America, EE.UU., America del Sur y España.
Limpiar nos zapatos con un detergente es importante cuando vamos de un parte del país al otro para evitar de propagar el hongo.
Sin embargo, varias acciones pueden ayudar el estado de los anfibios. La conservación de sus hábitat, reproducción en cautividad y el retiro de los especies invasivas puede ayudar las poblaciones de especies nativas!
AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2008. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Apr 15, 2008).
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Illustración:
Título: 8. La rana perdida! Objetivos:
Encontrar, observar y estudiar anfibios en su ambiente natural. Ayudar los niños a ganar una apreciación para la naturaleza en general. Ensenar a los niños ecología y biología del bosque tropical con énfasis sobre los anfibios. Pasar tiempo a fuera, en el bosque.
Lugar: En el bosque cerca de los caminos
Duración: 1 hora
Números de participantes: 10-30 minutes
Material: Pantalones Zapatos Poner su calcetín sobre los pantalones Un red para el maestro Un guía a los anfibios de Panamá
Consideración especial (de seguridad: - Hay serpientes en el parque, es un tema muy
serio. - Siempre debe mirar en frente cuando esta
caminando. - Nunca pone tu mano en un sitio que no puede
mirar bien. - Entonces el maestro siempre debe caminar al
frente de los niños. - Un permiso de ANAM puede ser necesario
Descripción: • Niños van caminar sobre los senderos del parquet y buscar ranas.
Serán permitidos de buscar dos metros de cada lado del sendero. Es muy importante que el maestro debería caminar al frente del grupo siempre para verificar
que no hay unos peligros y para supervisar la actividad. Varios hábitats van a ser visitados como el pequeño laguna a la entrada del parque. Una conversación corta seguirá cada animal observado o capturado. Una tentativa debería ser
hecho para clasificar el individuo y analizar sus características morfológicas. (Porque parece come eso?)
Aunque, el objetive de este ejercicio es de ensenar a la niños la ecología los anfibios, varios organismos van a ser encontrados como reptiles y los niños van a aprender conceptos de biología y de ecología en general.
Hechos relacionados: Un mínimo de 20 especies de anfibios viven en el parque natural metropolitano de Panamá, incluso la famosa rana con los ojos rojos. Hay especies activas durante el día como la Rhinella alata y otras activas en la noche. Aunque anfibios son muy dependientes del agua, ellas todavía se encuentran en una variedad de hábitat diferentes incluso ciénaga, praderas y bosques de tierras bajas. Algunas especies son terrestres como Craugastor fitzingeri y otras pasan la mayoridad sus tiempos en la cubierta forestal. Finalmente, la mayoridad de la cecilias pasa sus vidas en el suelo. La razón porque los anfibios son encontrados cerca de agua es porque su piel es permeable. Áreas húmedas son también ricas en insectos, lo comen anfibios. Mientras algunas especies son comunes, la mayoridad es rara. Este concepto puede ser aplicado a cuales que tipo de organismo! Niños van a realizar muy rápidamente que eso es verdad cuando ellos siempre van a encontrar las mismas especies.
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Ilustración:
Título: 9. Veneno Mortal Objetivos:
Introducir los niños a los mecanismos de defensa utilizados para los anfibios, especialmente las ranas.
Mostrar a los niños que las ranas venenosas de dardo son muy diversas. Ensenar a los niños conceptos básicos de biología, química y geografía que están relacionados
con los anfibios tóxicos.
Lugar: Adentro
Duración: 30 minutos
Números de participantes: 20-30, no limitación
Material: Algunos libros sobre los anfibios
Consideración especial (de seguridad: Ningún
Descripción: El maestro dará una pequeña conferencia interactiva, con un apoyo visual.
Hechos relacionados: Varios anfibios producen o liberan químicos tóxicos por la piel. Estos químicos incluso alcaloides
de gran alcance como batrachotoxina. Mientras varias especies de anfibios secretan toxinas benignas, otras secretan toxinas extremadamente potente.
Miembros de la familia Dendrobatidae son especialmente tóxicos. En Columbia, hay comunidades indígenas que usan las secreciones de algunas especies de estés ranas para cazar. Las secreciones serian aplicados a la punta de las flechas y de los dardos a soplar. La rana la mas toxica del mundo es la Phyllobates terribilis. Aunque los especies de ranas de Panamá son menos toxicas, uno tiene que hacer mucho cuida cuando manipula lo. Es importante de saber que no es la rana que sintetiza estas moléculas y que es en verdad los insectos que las ranas comen que da la partida toxica a estas ranas. En cautividad, las ranas a dardo pueden perder su veneno muy rápidamente. La toxina que se encontró sobre la piel de las Dendrobatidae juegan dos rolas. Primero, proteja las ranas de la ataques de depredador, y segundo, proteja las ranas de infección de bacterias y de hongos.
Las toxinas pueden ser de las glándulas granulares o las glándulas de moco, pero algunos anfibios producen alto niveles de tóxicos con glándulas parotoideas. Estes glándulas son muy visibles en el caso de la Sapo de Cana. Los anfibios tóxicos con frecuencia tienen colores muy vovos y eso es para advertir sus depredadores que son peligrosos. Estés colores como el vivo amarillo, rojo, naranja y azul se llaman coloraciones aposematicas.
Algunos especies de anfibios pueden imitar las colores de otras especies sin ser venenosos! . Hay también otras técnicas contre los depredadores. Por ejemplo, anfibios pueden tener técnicas
defensivas pasivas como se poner en una posición de manera que los depredadote pueden ver sus colores vivos cuando se sienten en peligro. Este técnica de defensiva se llama el Eunkenreflex.
http://www.venomdoc.com http://www.livingunderworld.org/amphibianArticles/article0011.shtml http://www.ansci.cornell.edu/courses/as625/2005term/Elaine/Dendrobates.htm#Meet
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Illustración:
Titulo: 10. Nuestra Mascota La Rana Objetivo:
Estudiar un anfibio en cautividad donde podemos mirarlo bien! Ensenar a los niños como cuidar una mascota. El mas importante es de ensenar a los niños cómo ser responsable
Locación: Al exterior, cerca de los caminos
Duración: 1 hora
Números de participantes 10-30, no hay restricción!
Material: Pantalones Zapatos Poner su calcetín sobre los pantalones Un red para el maestro! Un pequeño acuario
Consideración especial (de seguridad) : - Hay serpientes en el parque, es un tema muy
serio. - Siempre debe mirar en frente cuando esta
caminando. - Nunca pone tu mano en un sitio que no puede
mirar bien! - Entonces el maestro siempre debe caminar al
frente de los niños. - Un permiso de ANAM puede ser necesario!
Descripción: Los niños van a participar a la creación del acuario. Ellos van a buscar objetos naturales, a fuera, que pueden ser utilizados para decorar el
aquarium. Después, los niños van a caminar en el bosque, con el maestro para capturar una rana. Ellos van a traerla a la oficina y ponerla en su aquarium! Finalmente, los Niño serán responsable de cuidar para la rana. Ellos serán responsable también de darla agua y comida!
Hechos relacionados: • Sugerimos de usar Bufo marinus o Bufo typhonius. • Recuerda que los anfibios necesitan de quedarse húmedo y que ellos siempre necesitan un
plato de agua. • Una rana adulta debe ser alimentar una vez cada dos días. • El acuario debe ser adaptado a la rana. Debe parecer el más natural posible y ser un ambiente
seguro. • La rana debe tener bastante espacio para mover normalmente. • La rana puede ser manipulada pero con moderación. Es importante que los niños saben que las
ranas no les gusta ser manipuladas y que ellas tensionan muy rápidamente • ¡El acuario debe ser verificada un o dos veces por día para asegurarse que la rana esta bien! • Finalmente, el acuario debe ser limpiado regularmente y los residuos deben ser poniendo en la
basura!
Ilustración:
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Educational Activities (english version)
Part II : Educative Program on Amphibians
The complementary part of the project aims to initiate an educative program on amphibians, with a focus on students from 8 to 9 years old. It has been designed to teach them about the biology of amphibians, their role in the environment, their fragility, and their importance as health indicators of ecosystems. This part of the research project will help the park to offer a program of discovery activities to elementary schools, hence leading to better publicity, recognition, and access to funding. Also, as part of the park objectives, the activity is expected to enable children to experience a profound contact with nature. In turn, this should kindle their desire to learn more about amphibians and their habitats, and should stimulate their early willingness to protect their environment.
The educational project presented is separated into blocs of activities from which the teacher will create its own program (table 7). It will be at its own discretion to teach the matter, to adapt the activities to the students needs and manage its time.
The first discovery activity is an introduction to the world of amphibians. It initiates the students to the divisions of the animal kingdom using a taxonomic key, as well as explains the distinctions between the important subdivisions of amphibians (ie. frogs, toads, salamanders and cecilians). The use of a game of associations will help the children to understand the matter.
The second activity friendly explains the various evolutionary adaptations of frogs and toads to their environment, as well as bring to light their internal anatomy and their peculiar metamorphosis. The children will be asked to fill the blank identifying frog internal organs. Then, they will have to color the frog lifestages, and there will be a contest in which the best draws will be exposed.
The third activity is a set of mathematical problems to resolve using frog examples. They aim to use the scholar knowledge of students to teach them about the life of amphibians. The fourth one will be focussed on learning the frogs and toads of the park, including their specific calls. The class will be fallowed by a walk to the lagoon to try to see or ear frogs and toads.
The fifth discovery activity will focus on the various feet and hand adaptations of amphibians, and will encompass a jumping like a frog game. For the next activity presented, the children will have to mime frog behaviour. They will use their creativity coupled with the knowledge from previous activities to acheive the performance.
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For the seventh activity, the children will learn about the worldwide decline of amphibians. A short thematic hike in the park trail will show the students that many source of threats exist, and that they can help to diminish those threats. It should bring the student to think about the various ways they can help protect the amphibians and their habitats.
The eight activity is to learn to kids how to search for amphibians, as the real scientists do in their monitoring. They will be sensibilized to the importance of safety measures in the field, and will be teach about the various suitable habitats.
The nineth activity focuses on the defence mechanisms that amphibians uses in front of their predators. The focus will be on the dart-poison frogs, the Dendrobates, which are known for their bright colors and their human ancestral from which they have their name.
The last activity suggested is the pet frog. This is a special case that would require previous preparation and might require a permit from ANAM. The children y will participate in the creation of the frog terrarium. Furthermore, the park would gain from having a terratium with amphibians. This could be incorporated in the activities as it would be a great opportunity for children and the general public to see from closer the inhabiting animals of the park.
Table 7 : Discovery activities # Title of the activity Content Outside Duration 1 Introduction to amphibians Taxonomy and subdivisions of amphibians 1h 2 Adaptation of amphibians Lifecycle and internal organs 1h 3 Math problems Facts on frogs 30 min
4 Frog Calls Frogs and toads of the park, identification and calls X 1h
5 The ultimate amphi-mime Facts on amphibians X 30 min 6 Frog leap! Adaptations of feet X 30 min
7 Who is responsable? Amphibians decline and solutions to counter threats X 1h
8 In search for the lost frog Scientific research on amphibians X 1h 9 Deadly venom Normal lecture 30 min 10 Our pet frog Creation of a terrarium X 1h
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Title: 1. Introduction to amphibians Objectives: - Familiarize kids with the basic usage and principles of taxonomic keys - Emphasize what differentiates amphibians from the rest of the animal kingdom - Make clearer the differences between the main subdivisions of amphibians (frogs, toads,
salamanders) Location: Inside Duration: 1 hour Number of Participants: 10-30, no limit Material: - A big taxonomic key wallpaper - plastified animal pictures
Special (safety) consideration: none
Description: - In the first part of the activity, children are presented with the picture of a familiar animal (cat,
dog, chicken, worm) or of an amphibian (frog, toad, salamander). - By answering a systematic series of yes/no questions, the kids have to identify the animal picture
as corresponding to a frog, a toad, a salamander, or a non-amphibian. The questions and their implications will be visually accessible on the taxonomic key wallpaper. The teacher should emphasize the mechanism of the identification by sliding the animal picture along the arrows of the taxonomic keys..
- The teacher will then show the pictures of frog, toads, salamander and ceacilian while explaining to the children the differences between them.
Related Facts: Taxonomy of amphibians (..) Toads have shorter legs and so jump less far than frogs. They also have dry skin whereas frogs
have wet skin. Salamanders have a tail Caecilian are amphibians without legs that live in the ground. They ressemble to earthworms
or snakes. They can be as long as 1,50m!! Do frogs have teeth? Yes!! Only in the upper jaw, so they swallow their prey in one piece,
glup!
Illustration:
A big taxonomic key wallpaper
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Title: 2. Adaptation of Frogs Objectives: - Teach children the adaptation of frogs to their environment - Explain the metamorphosis that caracterize them - Explain the anatomy and morphology of a frog - Allow children to express themselves through the coloring - Show children that frogs are almost just like us! Location: Inside
Duration: 1 hour
Number of Participants: 10-30, no restriction
Material: - Coloring pencils - Photocopies of our stencils - A simple biology book for the teacher
Special (safety) consideration: none
Description: The entire class will look at each organ and body part one by one. The teacher will be
responsible of describing each organ and tell the children what are their functions. The children will simply fill-in the blanks!
The teacher will talk about the metamorphosis through which the amphibians go, and the children will have to color the stencil. The best drawns will be exposed.
Related Facts: Amphibian metamorphosis:
• The amphibians are characterized by their transformation from tadpole to adult. • In general, eggs are laid in water, many look like floating foam. • The tadpoles emerges from eggs and swim in water. They have gills, tail and small mouth. • The metamorphosis begin by the first hind legs, then front legs, lung development, migration
of eyes, enlargment of mouth, and finally the resorbtion of tail for frogs is the last stage. Role of Each Organ:
• Mouth: Orifice through which an organism takes in food and water • Brain: The control center of the nervous system. • Esophagus: Muscular tube through which food passes from the pharynx to the stomach. • Lung: Transport oxygen from the atmosphere into the bloodstream, and to release carbon
dioxide. • Liver: Various functions such as secreating the bile used for digestion. • Small intestine: Absorbtion of nutrients • Large intestine: Absorbtion of water and collection of waste • Stomach: break down of food • Pancreas: Dual-function gland, having features of both endocrine and exocrine glands. • Heart: muscular organ pumping blood through the blood vessels.
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• Spleen: Destroys old red blood cells and holds a reservoir of blood. • Urinary Bladder: Stores Urine • Cloaca: Where sperm, eggs, urine, and feces exit. • Anus: Where feces are expelled from the body.
Also The adult frogs are carnivorous, they eat insects, spiders, crustaceas, worms, leeches, as well as
snails and other mollusks. Frogs have a sticky tongue which it flips out rapidly to catch its prey.
AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2008. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Apr 15, 2008).
Illustration: Student sheet on frog metamorphosis:
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Teacher Sheet:
MOUTH
BRAIN
ESOPHAGUS
HEART
LUNG
LIVER
PANCREAS
STOMACH
SMALL INTESTINE
LARGE INTESTINE
URINARY BLADDER
SPLEEN
ANUS
CLOACA
MOUTH
BRAIN
ESOPHAGUS
HEART
LUNG
LIVER
PANCREAS
STOMACH
SMALL INTESTINE
LARGE INTESTINE
URINARY BLADDER
SPLEEN
ANUS
CLOACA
Students sheet - fill the blanks:
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Title: 3. Frog Maths Objectives:
To use the mathematical knowledge of students to learn about frogs Location: Inside
Duration: 30 min
Number of Participants: 10-30 no restriction
Material: - Pencils and sheet of papers - The problems stated in the sheet
Special (safety) consideration: None
Description: The children should already have some knowledge on the frogs from the previous activity. To introduce the activity, ask the children if they know how small and big are the frogs and
toads of he park, what does a frog eat? The teacher can write the questions on a board (if available) or give a sheet to each student. The children may work alone or in small groups. The questions are made to be from simpler to harder, and comprehensive.
Related Facts: See previous activities Illustration: Mathematical problems Question 1 There are 11 frogs calling in a small pond. A snake comes and eat 2 of them. How many frog remain? Answer: 11 - 2 = 9 frogs Question 2 The smallest frog of the park is the Pristimantis taeniatus measure 2,5 cm, whereas the biggest, the Leptodactylus savagei, is 7,2 times bigger, what is its size? Answer: The Leptodactylus savagei measures 2,5 X 7,2 = 18 cm Question 3 Frogs must cope with many threats from eggs to tadpole to adult. Say a mother frog lay 1000 eggs, and only half of them survive to the stage of tadpole. If of the tadpoles only one quarter will become adults, how many frogs will survived? Answer: 800/2 = 400/4 = 100 Question 4 A Hyalinobatrachium fleischmanni can eat 1 spider, 3 worms and 8 mosquitoes in one night. How many prey has it eaten? And so how many insects would the frog eat in 5 nights? Answer : 12 preys per night
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Answer: 60 preys in five nights Question 5 The frog Craugastor fitzingeri is an exceptional jumper. It can jump as much as 1,5 m long and can hop 5 times in a row. How far can he go? Answer: 1,5m X 6 = 9 m Question 6 During the dry season, the frogs Engystomops pustulosus migrate to ponds, which collected the water from the rainy season. If a 20cm2 pond can hold 6 frogs, how many frogs can survive with a 1m2 pond? Answer: 5 X 5 = 30 frogs Question 7 A frog is looking for its friend whom is sitting on the other side of a big log. The log measures 40cm by 30cm. The frog is wandering what would be the distance if he uses its long legs to jumps over the log. Help him to determine it. Answer: √(402 + 302) = 50 cm
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Title: 4. Frog Calls Objectives:
Familiarize children to the diversity of frogs and toads, as well as their calls Location: Inside and outside (trail to lagoon)
Duration: 1 hour
Number of Participants: Even number, from 10 to 30, no restriction
Material: - CD of frog calls - Pictures of the frogs
Special (safety) consideration: - When next to the lagoon, the children must be under the
supervision of the teacher. - Snakes is a serious issue! - Always look in front of you when you walk - Never put your hand somewhere you can’t see - Teachers should therefore lead the way and make sure
the path is safe Description:
To introduce the children to the activity, ask them to imitate what they think sound the call of frogs.
As an initiation to the calls, play the ones of the frogs living in the park and, at the same time, show their picture telling them the important characterisctics (eg treefrog, nocturnal,...) which ones would be written in the back of pictures.
After this initiation, play a game with children, dividing the class into two team. The goal of the game is to identify the frog species by its call. The winning team is the one with the higher score at the end. Having all the pictures exposed, play the call of a frog and the child of the first team must guess which one is it, by chosing the right picure. If the child wouln’t know, he could ask for a hint (one of the characteristics) but it would only counts for haft point. If the kid gives a wrong answer, the turn goes to the other team. To encourage the team spirit, the children have to pick up a frog name.
The second part of the activity is a walk in the trail to ear frog calls. The children will be asked to walk quietly in order to ear the frogs. A stop at the laggon will be done because it is the safest for children, and the most probable to ear calls. Since nor the children nor the teacher is expected to remember all the species call, volunteer kids will be asked to be able to imitated the calls in order to identify them back in the classrom.
Related Facts: The call of frogs is called «croak» and is different for each species. The sound is made by both
male and female, going through their vocal cords (larynx) in their throat. The males also have vocal sacs allowing them to croak louder than females. Those sacs are skin membranes located under the throat or next to the mouth, and which expend to amplify the call. Some frogs do not have vocal sac, and they tend to be
Frogs call mainly in the reproduction season to attract mates, but also to communicate in other life situation. Many species also have specific calls to defend their territory, before rain event or distress calls. Some species are called from their call, like the false-cricket frog in the US.
Illustration: Must include the pictures of the frogs, with the characteristics written on their back. Must include the CD of frog calls.
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Title: 5.The Ultimate Amphi-Mime! Objectives: - To share people’s knowledge and perceptions on what are amphibians. - To provide kids with a dynamic activity in which they can express themselves - To develop artistisc abilities and creativity through body language! Location: Outside, in an open area
Duration: 30 minutes
Number of Participants: 20-30, no restriction
Material: - A few pencils and paper!
Special (safety) consideration: None
Description: Each child writes on a piece paper something that one of their classmate will have to mime,
which relates to amphibians. (ex:jumping, climbing, feeding, sleeping) The pieces of papers are then folded in half and mixed in a hat or a bowl The children will form a circle so that everyone sees the performances. One after the other, the children will pick a mime from the hat and will perform the mime Their classmate will have to guess what the performer is miming! After each performance, the teacher should add a few comments on how it takes place in
nature Related Facts: IDEAS
Many amphibians are able to eat almost any prey item as long as it is small enough to fit in their mouth!
Many amphibians catch their prey with their mouth and tong but use their front legs to stuff the food down their throat.
While some frogs can jump over large distance other can only make small leaps. The cecilians move just like snake. Some arboral tree frogs move about almost like monkeys. The metamorphosis of most amphibians has a mimimum of three stage: egg, tadpole, adult. To retain their moisture, amphibians will close their eyes and bring their legs tightly along
their body. To avoid predation some frogs will either puff-up like a ball or extend their legs and walk like
a dog. Illustration:
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Titulo: 6. Frog Leap! Objetivos: - To explain the adaptation of frogs legs t their environment - Dar a los niños un sentido de la importancia del salto para el sobreviviendo de las ranas a contra
de los predatores. - Dar a los nilños la oportunidad de hacer exercisio fisico y - Provide kids with a dynamic activity in which they can exercise outside and take some fresh air - Develop both competition and cooperation abilities, along with team spirit. Location: Inside and Outside, in an open area
Duration: 1 hour
Number of Participants: 10-30, no restriction
Material: - 30 meter measuring tape - A few “flags” to mark distances - A rope or a string to mark the “starting line”
Special (safety) consideration: None
Description: The teacher will explain the difference in hands and feet evolution to their environment. The clecture will be fallowed by a game. Kids stand along a “starting line” and, one after the
other, compete to see who can jump farthest. The best distance is recorded. Kids are told that frogs can jump 20 times their length, and hence, had they been frogs, they
could have jumped more than 20 meters in length! With the help of the kids, the professor measures 20 m from the starting line. That is the
distance they could have jumped had they been frogs! How practical to escape predators! Cooperation activity: The kids relay each other to complete the 20 meters. A first kid jumps a
distance, say 1m. Starting from his landing point, a second kid jumps as far as he can (say another 1m, to add-up to 2 m), and so on. How many kids need to work together to add up to one “human size frog”
Related Facts: The capacity to leap is an important distinction between amphibians. While frogs are excellent
leapers, toads only jump over short distances. Salamanders and caecilians do not jump. Cricket frog, Acris crepitans, are the best jumpers among the frogs. They can jump 36 times
their length! (http://www.kiddyhouse.com/Themes/frogs/) In terms of distance, the record jump was set in South Africa during a frog derby. It measured
10.19 m (allaboutfrogs.org) Legs adaptation:
The structure of the paws and legs of frogs have evolved to fit to their environment and their life style, depending if they are living on the ground, in the water or in trees.
Webbed feet for swimming, but suction disks on the tip of toe for climbing (Arboreal Frogs) Extra-large webs for better gliding in the air, almost like flying Spines on the males' front feet for a better grip on the female during mating The specialist jumpers like the Hylidaes have special legs to inpower their jumps.
Illustration
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Title: 7. Who is Responsible? Objectives: - Teach children on the downfall of amphibians - Show children what is causing the decline of amphibian populations - Show chlidren that it is important to protect the environment! - Spend time outside and get rid of garbage. Location: Outside, along the trails
Duration: 1 hour
Number of Participants: 20-30, no restriction
Material: - Pants - Shoes - Socks over the pants
Special (safety) consideration: - Snakes is a serious issue! - Always look in front of you when you walk - Never put your hand somewhere you can’t see - Teachers should therefore lead the way and
make sure the path is safe Description:
The teacher should start the activity by giving a short lecture on the decline of amphibians. This short lecture should explain why amphibian populations are declining everywhere in the world. The causes should be clearly stated.
Along with the teacher, the children will go hicking in the forest People will then search for object or any sources of polution that may have a negative impact
for amphibians. The teacher will comment each visual encounters Finally, it may be a great opportunity to clean the park.
Related Facts:
Over 6 300 species of amphibians are thought to live on our planet. Unfortunatly, one third of these species are threatnned. Eventhough amphibians have been on this planet for over 300 milions years, in only 20 years we have lost 168 species and their rate of extinction will only increase! Most threatened species are found in tropics, especially in Central America, Asia and Indonesia. A variey of different causes are attributed to this decline such as: habitat destruction, introduced species, over-exploitation, climate change, UV-B radiation, chemical contaminants and disease (fungal pathogen).
In Panama, a the pathogenic fungus B. dendrobatidis is a serious issue! It is causing the decline of the famous “Rana dorada”. This fungus is having a devastating impact in the entire world, especially in Australia, Central America, USA, South America and Spain. Washing your shoes with a detergent becomes very important when going from one part of the country to another!
Various actions can be done to help this amphibian downfall. Habitat conservations, captive breeding and the removal of invasive species have been found to help native species.
AmphibiaWeb: Information on amphibian biology and conservation. [web application]. 2008. Berkeley, California: AmphibiaWeb. Available: http://amphibiaweb.org/. (Accessed: Apr 15, 2008).
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Illustration:
Title: 8. In search for the lost frog! Objectives: - Find, observe and study amphibians in their natural environment - Help the children gain an apreciation for wilflife and nature - Teach children on the ecology and biology of tropical rainforest, with a special interest on
amphibians! - Spend time outside! Location: Outside, along the trails
Duration: 1 hour
Number of Participants: 10-30, no restriction
Material: - Pants - Shoes - Socks over the pants - Nets for the teacher if possbible - A guide to the amphibians of Panama
Special (safety) consideration: - Snakes is a serious issue! - Always look in front of you when you walk - Never put your hand somewhere you can’t see - Teachers should therefore lead the way and
make sure the path is safe
Description: Kids will walk along the trails of the park and will search for frogs They will be allowed to search two meters on each side of the trails The teacher should always stay in front and supervise the activity Various habitats should be visited such as the small pond at the entrance of the park A short discussion should follow any animals seen or captured. An attempt should be made to
classify the animal and analyse its morphological features (why does it look the way it does?). Even though the goal of this exercise is to teach children about amphibians, a wide range of
different organisms will be encountered and kids will gain knowledge on biology and ecology in general.
Related Facts: At least 20 species of amphibians are thought to inhabitate the metropolitan nature park of
Panama including the famous red eyed-tree frogs! While some of these frogs are diurnal, such as Rhinella alata, others are completely nocturnal. Even though amphibians are highly dependant of water, they are still found in a variety of different habitats including swamps, grasslands and lowland forests. Some species are terrestrial such as Craugastor fitzingeri and others will spend almost all their life in the forest canopy. Finally, caecilians spend most of their time in the ground! The reason why most amphibians are found near water sources is because their skin is highly permeable. Wet areas are also rich in artropods which constitute an important part their diet! While few species are common, most species remain rare. This concept applies to any type of organisms! Children will quickly realize how true this is as they will always encounter the same species over and over again!
Illustration:
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Title: 9. A Deadly Defence Mechanism Objectives: - Initiate the children to the defence meachanisms used by amphibians, focus on frogs. - Show children how diverse poison arrow frogs are! - Teach children basic biology, chemistry and geography concepts relateds to venemous
amphibians! Location: Inside
Duration: 30 minutes
Number of Participants: 20-30, no restriction
Material: - A few books on frogs
Special (safety) consideration: None
Description: Normal lecture given by the teacher
Related Facts:
Many amphibians produce or simply release toxic compounds through their skin. These coumpounds include powerfull alkaloids such as batrachotoxin. While most species of amphibians produce only mild toxins, others produce extreamly potent compounds.
Members of the family Dendrobatidae are especially toxic. In Columbia various indigenous communities used the secretions produced by certain species for hunting. These secretions would be applied at the tips of arrows and blowdarts. Phyllobates terribilis is known to be one of the most toxic dart frog on earth! Even though species of frogs present in Panama are less toxic, great caution should applied when manipulating them. It is also important to know that it is not these frogs that synthesize these molecule but the insects on which they feed. In captivity, dart frogs quickly lose their venom. These toxins found on the skin of dart frogs are thought two play two role. It protects these frogs from predators and bacterial and fungal infections.
While most amphibians produce toxins thorugh granular glands and mucous glands, some amphibians also produce high concentration toxins through their paratoid glands. These glands are especially appearant in the cane toad!
Toxic amphibians are often highly colorated to warn their predators! These warning colors, such as bright yellow, red, orange, and blue are know as aposematic coloration!
Various amphibians will simply mimic other toxic species but may not secrete any toxic coumponds at all.
Anti-predation behaviors and passive defense posture often go hand in hand with toxic secretions. When feeling threatened, many amphibians will lies on their back or twist their body to expose and show their bright warning coloration. This adaptive behavior is known as the unkenrelfex!
http://www.venomdoc.com http://www.livingunderworld.org/amphibianArticles/article0011.shtml http://www.ansci.cornell.edu/courses/as625/2005term/Elaine/Dendrobates.htm#Meet
Illustration:
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Title: 10. Our Pet Frog! Objectives: - Study a real amphibian from up close! - Teach children how to take care of a pet animal. - Most importantly, teach children how to be responsible Location: Outside, along the trails
Duration: 1 hour
Number of Participants: 20-30, no restriction
Material: - Pants - Shoes - Socks over the pants - Nets for the teacher if possbible - A small terrarium
Special (safety) consideration: - Snakes is a serious issue! - Always look in front of you when you walk - Never put your hand somewhere you can’t see - Teachers should therefore lead the way and
make sure the path is safe - A permit from ANAM might be necessary!
Description: Children will participate in the creation of the frog terrarium. They will look outiside for natural objects that will be used to setup the frog’s terrarium. Kids will then walk along the trails of the park and will search of a frog. They will gently capture it and bring it back to the office. Finally, they will be responsible of the well being of the frog. They will provide it water and food and clean the terrarium.
Related Facts: • We suggest using either Bufo marinus or Bufo typhonius • Remember that amphibians always need to stay moist and that it will require a water dish
permenantly. • The adult frog should be fed every two days ! • The terrarium should be adapted to the frog. It should look as natural as possiblle but ramain a
safe environment. • The frog should have enough space to move normally! • It can be manipulated but with moderation. It is important to know that amphibians do not
particularly enjoy being manipulated. They will quickly stress. • The terrarium should be checked once or twice daily to verify that the frog is doing well. • Finally, the terrarium should be regurlarly cleaned and waste products should be removed.
Illustration: