1. Ch 10 Biodiversity

2. What Biodiversity Means
Variety of organisms in a given area
Genetic variation within a population
Variety of species in a community
Variety of communities in an ecosystem.

3. Biodiversity Certain areas contain extraordinary variety of species.
Need to understand and preserve biodiversity for our own survival

4. Biodiversity
about 1.7 million spp (species) most of which are insects.
Actual number is unknown.
Estimate of greater than 10 million total # of species
Exist in remote wilderness, deep ocean & even cities

5. Unknown Diversity

6. Species Are Connected to Ecosystems
Species play an important role in any ecosystem.
Every species is dependent on or depended upon by at least 1 other spp.
1 species disappears, a strand in a food web is removed.

7. keystone species
critical to functioning of ecosystem in which it lives
Affects survival and abundance of many other species in its community
Pacific Coast Kelp →Sea Urchins →Sea Otter
Prairie Dogs aerate soil in grasslands

8. Genetic diversity within populations
Critical factor in species survival
Increases chances for survival in environmental changes
Small and isolated populations are less likely to survive such pressures.

9. Bottleneck Effect Population decreases, genetic diversity decreases
Even if population is able to  again, an inbreeding within a smaller variety of genes will occur.
Population members may be more likely to inherit genetic diseases

10. Benefits of Biodiversity
Medical – Drugs
Industrial – Chemicals
Agricultural
Hybrid crops resistant to disease
Ethics
Aesthetics & recreation
Pets, wildlife viewing, nature enjoyment

11. Biodiversity at Risk
Sec. 10-2

12. Current Extinctions Midst of another mass extinction.
Rate is estimated to have  by a multiple of 50 since 1800
 25% of all species on Earth becoming extinct
Different from past b/c humans are primary cause of extinctions.
Amphibians extremely sensitive to environmental change

13. Species at Risk Migrating spp
Those that require large or special habitats
Those exploited by humans
Not illegal to hunt polar bears in Canada

14. Endangered species
In danger of extinction throughout all or a significant part of its range
Is under protection by regulations or conservation measures

15. Threatened species
species that has been identified to be likely to become endangered in the foreseeable future
983 species of plants and animals that are threatened or endangered (2002)

16. How Do Humans Cause Extinctions?
human population growth has accelerated and so has the rate of extinctions
Major causes:
destruction of habitats
Introduction of nonnative species
Pollution
Overharvesting of species

17. How Do Humans Cause Extinctions?

18. Habitat Destruction and Fragmentation
Humans build and harvest resources
Destroy & fragment habitats of other spp.
75% of extinctions are due to habitat loss
Cougars – Florida Panther
<80 left east of MI River

19. Invasive Exotic Species
Not native to a particular area
Familiar organisms are exotic if brought into area not normally found – cats & rats
Non-native: alien, exotic, foreign, non-indigenous, invasive
Threaten native spp.
Non-native sword fern in Hawaii rainforests – facilitates fire

20. Imported Species Aggressive & spread over large areas
Disrupt ecosystem
Interfere with human activity
One of the biggest threats to endangered species & biodiversity
Bio-Invasion –rapid expansion of species by direct or indirect human activities, to areas where they did not previously exist

21. Birds Starlings Congregate in large flocks Make lots of noise & mess
Drive away song birds by competing for food
Some feed on farm crops

22. Plants Intentional/accidental importation Purple loosestrife
Accidentally by a ship from Europe
Displacing food supply of many wild animals
Reduces carrying capacity (the number of species it can sustain) of wetlands it invades

23. Plants Water Hyacinth Crabgrass/dandelions/crown vetch
Considered a weed – a plant that grows in an unwanted location
Turning waterways into wetlands & choking life out of wetlands
Crabgrass/dandelions/crown vetch
weeds

24. Plants
Kudzu
Imported from Japan in 1876 for 100th celebration in Philadelphia
Used to help prevent erosion
Vines destroy forests by competing for sunlight
May take up to 10 yrs to kill

25. Kudzu
Kudzu – introduced to SE United States grows rampant, overtaking trees. In its native China, cold winters cause it to die back in cold weather, and several insects are natural predators

26. Invertebrates Zebra Mussel Native to Caspian Sea in Soviet Union
1st Spotted in US in 1988 in Lake St. Clair (between Lake Huron/Erie)
Accidental arrival on European freighter around ’85 – ’86 caused pop. explosion

27. Invertebrates Zebra Mussel Colonizing rock bottoms where fish spawn
Filter feeders may make water too clean for fish by eating all the algae
Clog industries’ intake pipes

28. Harvesting, Hunting, and Poaching
Thousands are harvested & sold as pets, houseplants, wood, food, or herbal medicine.
Poaching is the illegal harvesting of fish, game, or other species.

29. Pollution
Pesticides, cleaning agents, drugs, and other chemicals into food webs
Long term effects may not be clear for after many years

30. Pollution
Bald eagle was endangered because of a pesticide known as DDT
Now illegal to use in the U.S.
Still manufactured here & used around world.

31. Areas of Critical Biodiversity
Areas where a large number of endemic species exist
native to and only found in a particular place
Endemic plant species as indicator species: are sensitive to environmental changes
Giant Sand Treader Camel Cricket found in CO, NM & UT

32. Tropical Rain Forests Home to over half of world’s species
Despite covering only 7% of Earth’s land surface
Most have never been described
Unknown # are disappearing as forests are cleared for farming or cattle grazing

33. Coral Reefs & Coastal Ecosystem
Provide millions of people with food
Tourism revenue,
Coastal protection
Sources of new chemicals
Poorly studied
Not as well protected by laws as terrestrial areas are

34. Coral Reefs & Coastal Ecosystem
swamps, marshes, shores, and kelp beds
Threatening human Activities
Pollution
Development along waterways
Overfishing

35. Islands Limited # of mainland spp colonize new island
In turn evolve into new spp – very distinct & limited
Become endangered b/c of invasive spp
Hawaiian honeycreeper

36. Biodiversity Hotspots
most threatened areas of high species diversity
tropical rainforests, coastal areas, and islands
Have lost at least 70% of natural vegetation

37. Biodiversity Hotspots

38. The Future of Biodiversity
Sec 10-3

39. Captive-Breeding Programs
breeding species in captivity
But the question remains whether or not these restored populations will ever reproduce in the wild
California Condor

40. Preserving Genetic Material
Germ plasm
chromosomes and genes
Contained in protoplasm of germ cells
Seeds, sperm, eggs, or pure DNA
Germ-plasm banks store material in controlled environments for future use in research or species-recovery efforts.

41. Zoos, Aquariums, Parks, and Gardens
are living museums of the world’s biodiversity
species’ last hope for survival
rarely have enough resources or knowledge to preserve

42. Preserving Habitats and Ecosystems
Small plots of land for single population is usually not enough
protecting habitats of endangered and threatened species means preserving or managing large areas

43. Conservation Strategies
Protect entire ecosystem rather than individual species
save most species in an ecosystem instead of only ones been identified as endangered

44. Conservation Strategies
identify areas of native habitat that can be preserved, restored, and linked into large networks.
promote products that have been harvested with sustainable practices

45. Legal Protection for Species
US Congress – 1973
Endangered Species Act is designed to protect any plant or animal species in danger of extinction

46. Endangered Species Act, the U.S. Fish and Wildlife Service (USFWS)
list of all endangered and threatened species
Protection from human harm
Prevention of Federal Govt projects that harm
Recovery plan for each spp
Protect or restore habitat

47. Habitat Conservation Plans
land-use plan
attempts to protect threatened or endangered species across a given area
Allows some tradeoffs between harm to species and additional conservation commitments among cooperating parties

48. International Cooperation
International Union for the Conservation of Nature and Natural Resources (IUCN)
Facilitates efforts to protect species and habitats
Red Lists of species in danger of extinction around the world

49. Private Conservation Efforts
advises governments on ways to manage natural resources
works with groups like the World Wildlife Fund to sponsor projects
attempting to stop poaching in Uganda

50. CITES-Convention on International Trade in Endangered Species
Stop slaughter of African elephants for tusks
worldwide ban on all sales, imports, and exports

51. Private Conservation Efforts
World Wildlife Fund
encourages the sustainable use of resources and supports wildlife protection
The Nature Conservancy
helped purchase millions of hectacres of habitat preserves in 29 countries
Conservation International
ID biodiversity hotspots
Greenpeace International
Organizes direct and sometimes confrontational actions