El Camino Real Master Naturalist Trainingtxmn.org/elcamino/files/2010/03/TMN-Mammalogy-Pres.pdf ·...
Transcript of El Camino Real Master Naturalist Trainingtxmn.org/elcamino/files/2010/03/TMN-Mammalogy-Pres.pdf ·...
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Mammalogy El Camino Real Master Naturalist Training
John M. Tomeček
11 Major Characteristics:
Hair
Integument
Teeth
Movable Eyelids, External Fleshy Ears
Four Limbs
Four-Chambered Heart
Respiration with lungs, larynx, and muscular diaphragm.
Highly developed Brain
Endothermic and Homeothermic
Internal Fertilization and Development of Eggs
Mammary Glands
What is a Mammal?
Monotremes
Marsupials
Placentals
Three Major Groups:
Lay Eggs
Mammary Glands, but no teats
Special Hairs
3 living species-All in Australia and New Zealand
Monotremata
Bear Live Young Mammary Glands and Teats Pouch called “Marsupium”, poorly developed offspring
leave cloaca and crawl to pouch. Limits adaptations for forelimbs. Why?
How does this benefit survival? Most in Australia, some in North America
Why? Where there more in the Americas?
Marsupials
Most mammals we are familiar with.
Mammary Glands and Teats
Bear fully developed live young.
Widest evolutional diversity of species.
What are the survival advantages?
Placentals
3 Million Years Ago
Isthmus of Panama finally became connected
Familiar Species with know came to N. America!
Birds, Freshwater Fish, Mammals, Reptiles, and Amphibians.
Lasted long enough for slow-dispersal species to migrate.
Great American Interchange
Mammal Skulls
Four Types
Incisors
Canines
Premolars
Molars
“I-C-P-M”
Homodont vs. Heterodont Dentition
“Peg-Like Teeth”
Teeth
Marsupials (1)
Insectivores (5)- Shrews, Moles
Bats (30)
Carnivores (28)
Seals (1)
Rodents (63)
Rabbits (5)
Hoofed Mammals (8)
Armadillos (1)
Manatees (1)
Whales and Dolphins (14)
Texas Mammals
Hairy legged vampire bat
-One Specimen taken in May 1967 an abandoned railroad tunnel near Comstock, Val Verde County.
Little brown myotis- One Specimen near Fort Hancock, Hudspeth County
Northern myotis- One Specimen near Winterhaven, Dimmit Co.
Accidental Mammals
Kangaroo Rat (Dipodomys elator)- STATUS-State Threatened
Gulf Coast Kangaroo Rat (Dipodomys compactus)-STATUS: Not well known. THREATS-development on Mustang and Padre Islands.
Attwater’s Pocket Gopher (Geomys attwateri)- STATUS-locally common. Threatened by fireants and hybridization.
Texas Pocket Gopher (Geomys personatus) STATUS: Good
Llano Pocket Gopher (Geomys texensis)-STATUS: Locally abundant, threatened by limited range.
Strecker’s Pocket Gopher (Geomys streckeri)- STATUS: Unkwnown. Threatened by limited range, and full range unknown.
Our Unique Texas Mammals
Southern Short-tailed Shrew: Eastern one-fourth of Texas; venomous; highly reproductive; few survive 2 years.
Elliot’s Short-tailed Shrew: Aransas, Montague, and Bastrop Counties; slightly venomous
Least Shrew: Eastern and Central Portions of Texas, West in Panhandle to NM; inhabit grasslands and consume only animal matter.
Desert Shrew: Western 2/3 of Texas, do not use underground burrows; eat larval stage of insects
Eastern Mole: South, East, Central, and Panhandle. Nature of Soil restricts their distribution.
Order Insectivora
30 Species in Texas
One species- Mexican long-nosed bat-is only known from Big Bend National Park.
3 Species Threatened
Order Chiroptera
Only true flying mammals
Amazing Adaptations for Flight and Locations of prey.
2nd most number of species of all mammals (around 925)
Consume wide variety of food items, from fruits, pollen, meat, fish, and blood.
As a result lots of specially adaptated mouths, tongues, and limbs.
Order Chiroptera
Southern Yellow Bat:
Status: State Threatened
Threats: Limited Distribution, Limited Roost Sites (Palm Trees)
Common in Cameron County, present to Corpus Christi along coast
State Threatened Bats
Rafinesque’s big-eared Bat
Status: State Threatened
Occurs: Eastern Portions of the state, notably pine forests.
Threats: Habitat Degredation: Commercial logging and lack of species understanding
State Threatened Bats
Spotted Bat
Statsu: State Threatened
Occurs across N. American
Known in Texas from Big Bend National Park
State Threatened Bats
69 Species in Texas
3 State Threatened Species
Order Rodentia
By far the most speciose order of mammals.
Range in size from small mice, barely weighing half an ounce, to Capybara which weigh over 140 pounds.
Inhabit all areas of the globe.
Single pair of incisors followed by a gap (diastema) before other teeth.
Incisors are self-sharpening.
Order Rodentia
White-footed Mouth
Hispid Cotton Mouse
Prairie Vole: Uncommon, only in Lipscomb and Hansford Counties
Presidio Mole
Gray-footed Chipmunk
Prairie Dog-An ongoing success story
Texas Rodents-Common and Uncommon
12 Species, formerly 9! Why?
Texas Pocket Gophers
Hares, Pikas, Rabbits
Native to all continents but Australia and Antarctica---but now many in Australia
Two Incisors-An easy way to separate from rodents
Testes in males located in front of penis-as in marsupials
Order Lagomorpha
Swamp Rabbit-Eastern 1/3 of Texas
Eastern Cottontail- Eastern ¾ of Texas
Davis Mountains Cottontail-Uplands in Wester ½ of State
Black-tailed Jackrabbit- All areas except the Big Thicket
Texas Lagomorphs
Artiodacyla includes deer, camels, pigs, javelina, etc.
“Even-toed Ungulates”
Cannon Bones
Perissodactyla-Horses, Donkeys, Zebras, Rhinos
“Odd-toed Ungulates”
Why the heck am I mentioning things that aren’t Texan?
Orders Artiodactyla and Perissodactyla- The Hoofed Mammals
Pronghorn Antelope
Javelina
Elk
Bison
Texas Hoofed Mammals
Feral Hogs
Texas’ Original Wildlife Restoration Success Story
White-Tailed Deer
Mule Deer
Consume other food items than meat, but large part of diet is meat.
Specialized tooth combination: the carnassial pair. The fourth upper premolar and first lower molar.
Skulls, Bodies Diverse
Also aquatic carnivores: Seals, sea lions, and walrus.
Order Carnivora
Felidae: Cats, 6 Species in Texas
Margay only known from one historical record
Jaguar extirpated
Canidae: Wolves, Coyotes, Foxes, 6 Species in Texas
Procyonidae: Raccoons and Coatis, 3 Species
Ursidae: Bears
Historically Grizzly and Black Bears, now Grizzly extirpated
Mustelidae: Weasels, Skunks, Otters
11 Speices-6 of which are skunks
Order Carnivora in Texas
Status: Federally Endangered
Extant Populations: Laguna Atascosa NWA and northern Willacy County
Threatened by loss of range and habitat and small population size.
Ocelot
Status: Federally Endangered
Range: Far South Texas: Cameron, Hidalgo, Starr and Willacy Counties
Last known report in 1986.
Thought to be extirpated, but not confirmed
Jaguarundi
State Threatened
Why?
Loss of riparian woodland
Very little is known about their life histories and ecology in our region.
Coati
Three Areas: East Texas
Panhandle
West/South Texas
Is there any hope for bear recolonization? TPWD East Texas Habitat
Suitability
Sightings in East Texas! Where the heck from?
Bears from Mexico.
Panhandle Bears?
Will the West Texas and East Texas Populations meet in Central Texas/
Black Bears in Texas
Livestock Concerns
Highway Concerns
Landowner Attitudes
Bear Season in TX until 1986
Encroachment of Urban Spaces
What can we do to help address everyone’s concerns?
Human-Bear Conflicts
Furbearers of Texas
Many furbearers are not endangered, but special tags must be acquired from TPWD for their take and transport.
Why?
Some things to know:
Populations in Texas recovering from previous lows.
Why did they decline?
Species widely distributed from Texas to Canada
Otter face issues from habitat loss, highways, dams, and human conflicts.
River Otter
Widely distributed across Texas in all ecoregions.
Range 35-50 Lbs on average.
Tail usually 6-12 in long.
Individual Spot Patterns.
Populations seem stable.
Bobcat
Water-dwelling.
Eastern ½ of Texas to North Panhandle
Mink
Little known about this mammal.
Very little significance as furbearer.
Inhabits Eastern, Southern, and Western Texas.
Long-tailed weasel
Foxes of Texas
Inhabit Western ½ of Texas
Smallest of Foxes (4-6 lbs)
Natural habitat is grasslands, deserts. Have adapted to pastures, rangeland, and fields.
They tend to inhabit areas with sandy soils to dig dens.
Currently threatened by habitat loss.
Swift Fox (Kit Fox)
Introduced to Texas in 1895 for hunting.
Expanded rapidly to occupy possible habitats.
Occurs in all but far West Texas.
Red Fox
Statewide Distribution
Native species of Fox
Only canid that can climb trees!
Populations seem stable to expanding, but much room for expansion of research.
Grey Fox
Populations growing and growing.
Recovered from lows last century.
Populations centered around non-flowing water in Eastern, South, and Central Texas.
Are they rodents? Yes!
Beaver
Hooded Skunk
Western Spotted Skunk
Eastern Spotted Skunk
All three in decline, but unclear why. Several studies ongoing. Habitat decline likely the key.
Hog nosed skunk: 2 subspecies, 1 extirpated, 1 still common.
Research needs are great for information on ecology, behavior, and management recommendations
Skunks of Texas
Both found throughout state, except ringtail in extreme South Texas.
Raccoon Population Stable.
Ringtail Populations Unknown.
Is it a cat?
Nope, they are both members of the raccoon family.
Ringtails and Raccoons
Inhabits all but Deep East Texas, but fairly uncommon in most of central Texas.
Does not tolerate habitat fragmentation and modification well.
Extremely territorial, burrowing animal.
Abundant where present.
American Badger
Coyotes and Wolves
Formerly inhabited Western 2/3 of State.
Last authenticated report in Brewster County in 1970.
Gray Wolves in Texas
Once abundant throughout SE US, especially forests, swamps, and coastal prairies.
Recent studies suggest it may have been a hybrid species of grey wolf and coyote.
Though extirpated in Texas, a wild population exists in North Carolina.
Red Wolves
Tracks
Scat
Hair
Other Sign
Recognizing Mammal Sign
Tracks
Scat
Hair
Other Sign
Estimating/Surveying Populations
Capture Techniques
How do Wildlife Biologists Study Mammals?
Why do we need to estimate population size?
Why should the average citizen care?
Who does it?
Census vs. Survey vs. Index
How do we figure it all out?
Why survey?
What does it mean?
How popular is it?
How do you do it?
Tags
Collars
GPS
Radio Telemetry
Remote Cameras
Mark/Recapture.
Distance Sampling
What is it?
Who uses it?
How does it work?
Other Sampling Methods
Live Capture?
Live Traps.
“Virtual Capture” with Cameras
Leg-hold Traps
Body Traps
Enfenced Areas.
Lethal Capture
Snares
Crush-type traps.
Why use these? Who?
Capturing Mammals
Melanism.
You are the ambassadors of the wildlife profession to the public.
Thank you so much!
Thank you!