Chapter 17:Preserving Earth’s Biological Diversity

What is a species?

Related terms

• Biological diversity: the # and variety of organisms.

• Genetic diversity: variation within a species.

• Species Diversity: the # of species

• Ecosystem diversity: variation within an ecosystem.

I. How many Species are there?

• 99.95 % of species that have existed are now extinct.

• ~1.8 million species identified at present.• # may range from 5-100 million species, we

don’t know.• 270,000 plant species• 45,000 vertebrate species• 950,000 insect species!• 10,000 new species identified each year.

Why bother conserving?

• Why do we need all of of these species?

• Can’t some be eliminated without any real consequences?

II. Why we need organisms

Salix babylonicaSalix babylonica

Aspirin The discovery of aspirin dates back to the 5th century B.C., The discovery of aspirin dates back to the 5th century B.C.,

when Hippocrates used a powder from the bark of a willow tree when Hippocrates used a powder from the bark of a willow tree to ease minor pains, reduce fevers and to help with childbirth. to ease minor pains, reduce fevers and to help with childbirth.

The willow tree powder was actually salicin, the The willow tree powder was actually salicin, the

pharmacological ancestor to the family of drugs known as salicypharmacological ancestor to the family of drugs known as salicy

                                                                                          

                                    

Ecosystem Services & Organisms

A. Ecosystem Services & Organisms

• Organisms provide essential ecosystem services.

• Ex: Bacteria and Fungi are decomposers that cleanse and recycle nutrients within an ecosystem.

• Forests recharge groundwater, hold soil, act as a Carbon sink.

Genetic Reserves

Maintaining a broad genetic base is critical for long-term health and survival of a species.

Scientific Importance of Genetic Diversity

Medicinal, Agricultural, & Industrial Importance of

Organisms

Aesthetic, Ethical, & Spiritual Importance of Organisms

Endangered & threatened Species

Protected Species Threatened species endangered species Extinct Species

• Extinction: the permanent loss of a species, therefore a permanent loss in species diversity.

• There has always been low amounts of “background extinction.” Occasionally, there are mass extinctions.

• Current rate of extinction is 100- 1,000 x the usual rate!

• Endangered species have populations that are so low that they are in danger of extinction throughout all or a significant part of their range.

• Threatened species have numbers that are quite low.

Species Preservation

Species Preservation

Species Preservation

Species Preservation

Endangered & threatened Species

• Endangered & threatened species often have limited natural ranges & low population densities.

• Endangered & threatened species may also have low reproductive rates or very specialized nutritional or reproductive requirements.

• Many island species are Endangered species.

• Habitat fragmentation: the break up of large areas of habitat into small, isolated patches (islands) is a major threat to the long-term survival of many species.

Species Preservation

Where are the greatest problems?

• Tropical rain forests- Loss of 1 acre/sec.

• “Hotspots”- Small areas that contain many species.

• 43% of all endangered species need wetland habitat to live.

• 60,000 acres of wetlands are destroyed in the US annually.

Human Causes of Species Endangerment

• Most human activities contribute to a reduction in biological diversity

• Habitat Destruction and fragmentation are the major causes of the current decline in biological diversity.

• This loss of habitat reduces a species biological range & ability to survive.

Human Causes of Species Endangerment• Biotic pollution: the introduction of

of a foreign species into an area where it is not native.

• Humans have accidentally and/or intentionally imported organisms to areas where they have no natural enemies leading to the disruption of existing ecosystems.

• Examples include the Japanese beetle and the Gypsy moth.

Introduction of Exotic Species

Introduction of Exotic Species

• Examples: Zebra Mussels,

Human Causes of Species Endangerment

• Exotic Species may compete with native species for food or habitat (niche) or may actually prey upon the endemic species. (aka Invasive species such as purple loosestrife)

Human Causes of Species Endangerment• Pollution, such as acid rain, pesticides,

O3 depleting compounds, as well as climate warming atmospheric pollutants (CO2, CH4) contribute to the decline of species.

• Major air pollutants include: carbon monoxide, hydrocarbons, and particulates.

• Nitrogen oxides and sulfur dioxide combine with water vapor creating acid rain problems.

Water Pollution

• Major water pollutants include: heat, sewage, and chemicals such as phosphates, heavy metals, and PCB’s.

Human Causes of Species Endangerment• Commercial harvest is the removal of live organisms from

nature. Illegal commercial trade of rare animals & plants supplies a thriving black market, but regulated commercial harvest may sustain species from an economic standpoint.

Human Causes of Species Endangerment

• Uncontrolled hunting, trapping, and fishing still occur in many parts of the world.

• The extinction of the dodo bird and the passenger pigeon resulted from such activities.

Human Causes of Species Endangerment

The last known individual of the species, a female named Martha, died in 1914 in the Cincinnati Zoo and is now on display in the U.S. National Museum of Natural History.

Human Causes of Species Endangerment• Overexploitation of species: the

over hunting or harvesting of species without regard to their biotic potential.

Human Causes of Species Endangerment• Efforts to eradicate a pest species or predator.

• Illegal commercial hunting has a great impact (especially on larger animals. (K selected)

Species Warning signs…

• Bellwether species (Sentinel species or Indicator species)

• Ex. Amphibiams

Conservation biology

• The scientific study & protection of biological diversity.

• In situ conservation addresses loss of diversity in nature.

• Includes parks, sanctuaries, refuges, & other protected areas.

• Restoration ecology attempt to restore a degraded area (derelict lands) by applying ecological principles.

• Species population community ecosystembiome

Conservation biology

• Ex situ conservation addresses loss of diversity in controlled settings & involve captive breeding programs & storing genetic material- “Conservation in a human controlled setting.”

• (Zoos, Aquaria, botanical gardens, and seed banks are examples of Ex situ conservation.)

Species Preservation• Some efforts to sustain endangered

species have included habitat protection (wildlife refuges and national parks) and wildlife management (game laws and fisheries).

• Animals which were once endangered are now successfully reproducing and increasing their numbers.

• Examples of endangered animals which are responding to conservation efforts and beginning to make a comeback are the bald eagle Haliaetus leucocephalus and the peregrine falcon Falco peregrinus .

Endangered Species Act

• Law enacted in 1973

• Protects endangered and threatened species in the USA.

• Legal protection for about 1,200 species.

• Requires an “action plan” for recovery

• Has resulted in some economic distress

Species Preservation• The peregrine falcon

Falco peregrinus .

Species Preservation

http://www.state.ia.us/government/dnr/organiza/fwb/wildlife/pages/falconindex.htm

Species Preservation

Species Preservation

Species Preservation

Species Preservation

Species Preservation

Species Preservation

Species Preservation

Species Preservation

Wildlife Management

• An applied field of conservation biology that focuses on the continued productivity of plants & animals.

• Involves the regulation of hunting & fishing & the management of food, water, & other habitat components.

• One species which is a major problem in the Artic is the snow goose- Very adaptable!

Conservation organizations• Various organizations help to

educate policy makers and the public about the importance of biological diversity. Organizations also take direct action in addressing the problem.

• Sierra Club• W.W.F.• EarthFirst!• U.S. Fish & Wildlife Service• Greenpeace

• There are laws which regulate and guide the use of natural habitats.

• Ex: SEQR- State Environmental Quality Review Act

• A New York State law designed to provide the opportunity for citizen review and comment of the environmental impact of any proposed development that has been determined to have significant effect on the environment.

Policies & Laws

What can we do about declining biological diversity?

• Increase Public Awareness

• The general public & lawmakers must become more aware of the importance of our biological heritage.

What can we do about declining biological diversity?

• Support research in Conservation Biology

• Funding must be found for additional research in both basic & applied fields relating to conservation biology.

What can we do about declining biological diversity?

• Support the establishment of an International System of parks with a minimum of 10% of the Earth’s land area.

What can we do about declining biological diversity?

• Control pollution which damages humans as well as other organisms.

What can we do about declining biological diversity?• Provide economic incentives

to landowners & other local people to manage their lands in an environmentally sustainable way.

Ex: Ecotourism in Costa Rica

The End