5.1 Vanishing Species

• Biodiversity– Increases as you move toward the equator.

• Tropical rainforest, coral reef, large tropical lakes

– Larger areas (islands) have more biodiversity (more habitats)

– # of Species depends on the # of habitats.

www.cspo.org/gck/images/Biodiversity%202.jpg

5.1 Vanishing Species

• Importance of Biodiversity– Living things are interdependent

• Loss of one species may have large effects on other species in the area.

– Loss of habitat, food source, niche, protection, etc.

– Provides Stability• Stop spread of disease

– Humans Count on it• Hybrid food, medicine, other products

5.1 Vanishing Species• Loss of Biodiversity - Extinction

– Background extinction: natural amount• 1-10 sp/year (based on 10 million sp)

– Current rate• 100-10,000 sp/year

– Causes• Human pop. growth, • habitat loss, • land exploitation

5.1 Vanishing Species• Extinct

– Eastern Cougar (2011)

– Carribean Monk Seal (1952)

• Endangered– California Condor– Sea Turtles– Tiger– Alligator Snapping

Turtle– W. Lowland Gorilla

• Threatened

-African elephants

-Bald Eagle

5.1 Vanishing Species• Threats

– **Habitat Loss** • Farm land, firewood, development

– Habitat Fragmentation• Decreases biodiversity, geo./genetic isolation, LF

– Edge effect• Roads, field, water, etc.

www.adb.org/.../img/biodiversity.gif

5.1 Vanishing Species• Threats cont’.

– Habitat Degradation1. Air – burning fossil fuels, volcanoes, fires

– Acid precipitation takes nutrients out of soil, damages tissues, changes pH (range of tolerance)

2. Water pollution – fertilizers, animal waste, detergents, trash– Causes Algal blooms = take O2 away

3. Land pollution- trash, pesticides, chemicals– Biological magnification

Threats Cont’

• Exotic Species (non-native)-– Not native to an area:

• Disrupt ecosystems, communities, etc

• Population explodes due to lack of predators– Use up resources

• Zebra Mussel– Introduced to Great Lakes in ballast water of ships

– Blocking food chains

» Eat algea

» Disturb fish reproduction

» Disturb nutrient flow

5.2 Conservation of Biodiversity• Conservation – to protect biodiversity

– Legal: US Endangered Species Act (1973)• Endangered and threatened sp. protected

– Preserving Habitat: National Parks • 1872 – Yellowstone Nat. park

– Habitat Corridors: protected areas for migration

5.2 Conservation of Biodiversity– Sustainable Use: use resources, but

maintain ecosystem– Reintroduction programs: breeding

endangered species, then release them back to their habitat

• California Condor

– Captivity: keeping of animals by humans• Can be the only place to find species• Animals cannot be reintroduced

– Giant Tortoise– Barbary Lion