Biodiversity

1. Biodiversity Chapter 13 Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

2. Outline: • Biodiversity and Species Definitions • Benefits of Biodiversity • Threats to Biodiversity • Human Caused Reductions • Biodiversity Protection • ESA • Minimum Viable Populations • CITES • Captive Breeding Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

3. BIODIVERSITY AND SPECIES • Biodiversity Types: • Genetic Diversity - Measures variety of different versions of same genes. • Species Diversity - Measures number of different kinds of organisms within a community. • Ecological Diversity - Measures richness and complexity of a community. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

4. What Are Species • Species - Organisms of the same kind that are able to breed in nature and produce fertile offspring. • Underlying idea is that reproductive isolation prevents gene exchange and gives rise to new species. • Hybridization creates a dilemma. • Species identification often based on morphological characteristics. • DNA sequencing Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

5. How Many Species • Currently 1.4 million species identified. • Estimates range between 3-50 million. • May be 30 million insect species. • May be 10 million species on ocean floor. • Invertebrates make up 70% of all known species, and probably most of yet to be discovered species. • Tropical rainforests and coral reefs are biodiversity hotspots. • NA and Europe only contain 10-15%. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

6. BENEFITS OF BIODIVERSITY • Food • As many as 80,000 edible wild plant species could be utilized by humans. • Drugs and Medicines • More than half of all prescriptions contain some natural product. • Pharmaceutical companies actively prospect tropical countries for products. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

7. Benefits of Biodiversity • Ecological Benefits • Soil formation, waste disposal, air and water purification, nutrient cycling, solar energy absorption, and biogeochemical and hydrological cycles all depend on biodiversity. • Can a system function without all its integral parts ? Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

8. Benefits of Biodiversity • Aesthetic and Cultural Benefits • Cultural diversity inextricably linked to biodiversity. • USFWS estimates Americans spend $104 billion annually on wildlife-related recreation. • Ecotourism can be an important form of sustainable economic development. • Existence (intrinsic) value. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

9. THREATS TO BIODIVERSITY • Extinction - Elimination of a species. • Normal process • In undisturbed ecosystems, background rate appears to be one species per decade. • In this century, human impacts have accelerated that rate, causing perhaps hundreds to thousands of extinctions annually. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

10. Natural Causes of Extinction • Fossil Record suggests more than 99% of all species ever in existence are now extinct. • Most went extinct before humans arrived. • End of Cretaceous - Dinosaurs and 50% of existing genera disappeared. • Permian period - Two-thirds of all marine species and nearly half of all plant and animal families died out. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

11. Human-Caused Reductions in Biodiversity • Habitat Destruction • Biggest reason for current increase in extinction is habitat loss. • Habitat fragmentation divides populations into isolated groups vulnerable to catastrophic events. • Hunting and Fishing • Over-harvesting of game species. • American Passenger Pigeon • Whales Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

12. Habitat Fragmentation - Cadiz Township, WI Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

13. Human-Caused Reductions in Biodiversity • Commercial Products and Live Specimens • Wildlife smuggling is very profitable. • Leopard fur / Rhinoceros horns • US Annual pet trade in wild species: • 2 million reptiles • 1 million amphibians and mammals • 500,000 birds • 128,000 tropical fish (often caught with cyanide above coral reefs) Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

14. Predator and Pest Control • Many animal populations have been greatly reduced or exterminated because they are regarded as dangerous to humans or livestock. • Animal control costs $20 million in federal and state funds annually. • 700,000 birds and mammals annually. • 100,000 coyotes Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

15. Predator and Pest Control • Exotic Species Introductions • Exotic organisms - Organisms introduced into habitats where they are not native. • Biological Pollution • Kudzu Vine • Purple Loosestrife • Zebra Mussels • Asian Long-Horned Beetles Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

16. Predator and Pest Control • Diseases • When a disease is introduced into a new environment, natural balance may be tipped, leading to an epidemic. • Pollution • Toxic Pollutants • Pesticides • Lead • Genetic Assimilation Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

17. BIODIVERSITY PROTECTION • Hunting and Fishing Laws • By 1890’s, most states had enacted some hunting and fishing laws. • General idea was pragmatic, not aesthetic or moral preservation. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

18. Endangered Species Act • Established in 1973. • Endangered are those considered in imminent danger of extinction. • Threatened are those likely to become endangered, at least locally, in the near future. • Vulnerable are those that are naturally rare or have been locally depleted to a level that puts them at risk. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

19. Endangered Species Act • ESA regulates a wide range of activities involving Endangered Species: • Taking (harassing, harming, pursuing, hunting, shooting, killing, capturing, or collecting) either accidentally, or on purpose. • Selling • Importing into or Exporting out of the US • Possessing • Transporting or Shipping Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

20. Endangered Species Act • Currently, US has 1,500 species on its Endangered and Threatened lists, and about 500 candidate species waiting for consideration. • Number reflects more about human interests than actual status. • Invertebrates make up 75% of all species, but only 9% of T/E list. • Listing process is extremely slow. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

21. Recovery Plans • Once a species is listed, USFWS is required to propose a recovery plan detailing the rebuilding of the species to sustainable levels. • Total cost of all current plans = $5 billion. • Opponents have continually tried to require economic costs and benefits be incorporated into planning. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

22. Private Land and Critical Habitat • Eighty percent of habitat for more than half of all listed species is on non-public property. • Supreme Court has ruled destroying habitat equates to taking. • USFWS has been negotiating Habitat Conservation Plans (HCP) with private landowners. • Landowners allowed to harvest resources as long as species benefit. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

23. Reauthorizing ESA • ESA officially expired in 1992. • Proposals for new ESA generally fall into two general categories: • Versions that encourage ecosystem and habitat protection rather than individual species. • Safe Harbor policies that allow exceptions to critical habitat designations. • (Economic Considerations) Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

24. Minimum Viable Populations • Minimum Viable Population is the minimum population size required for long-term viability of a species. • Island biogeography - Small islands far from a mainland have fewer terrestrial species than larger, closer islands. • MacArthur and Wilson proposed that species diversity is a balance between colonization and extinction rates. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

25. Minimum Viable Populations • Diversity Loss in Small Populations: • Founder Effect • Few individuals start a new population. • Demographic Bottleneck • Few individuals survive catastrophe. • Genetic Drift • Random reduction in gene frequency. • Inbreeding • Mating between related individuals. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

26. Habitat Protection • Latest management strategy is preservation of ecosystems supporting maximum biological diversity rather than species-by-species approach. • Gap Analysis - Conservationists and wildlife managers look for unprotected landscapes that are rich in species. • Broad-scale, holistic approach. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

27. Biodiversity Map Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

28. International Wildlife Treaties • Convention on International Trade In Endangered Species (CITES) - 1975. • Regulated trade in living specimens and products derived from listed species. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

29. CAPTIVE BREEDING • Breeding programs in zoos and botanical gardens are one method of saving threatened species. • Repositories of genetic diversity. • Most mammals in NA zoos are now produced from captive-breeding programs. • Some zoos now participating in reintroduction programs. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

30. Captive Breeding • Zoos have limited space for captive breeding. • How many can / should we save ? • Ultimate problem is that natural habitat may disappear while we are conserving the species itself. • Another alternative is to attempt to save species in the wild. • Provide funding for protection in native habitats. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

31. Summary: • Biodiversity and Species Definitions • Benefits of Biodiversity • Threats to Biodiversity • Human Caused Reductions • Biodiversity Protection • ESA • Minimum Viable Populations • CITES • Captive Breeding Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.

32. Cunningham - Cunningham - Saigo: Environmental Science 7th Ed.