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Sustaining Biodiversity: The Species Approach. Chapter 9. Characteristic. Examples. Low reproductive rate (K-strategist). Blue whale, giant panda, rhinoceros. Blue whale, giant panda, Everglades kite. Specialized niche. Elephant seal, desert pupfish. Narrow distribution.
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Characteristic Examples Low reproductive rate (K-strategist) Blue whale, giant panda, rhinoceros Blue whale, giant panda, Everglades kite Specialized niche Elephant seal, desert pupfish Narrow distribution Bengal tiger, bald eagle, grizzly bear Feeds at high trophic level Fixed migratory patterns Blue whale, whooping crane, sea turtle African violet, some orchids Rare Snow leopard, tiger, elephant, rhinoceros, rare plants and birds Commercially valuable California condor, grizzly bear, Florida panther Large territories Stepped Art Fig. 9-5, p. 188
Loss of Habitat Is the Single Greatest Threat to Species: Remember HIPPCO • Habitat destruction, degradation, and fragmentation • Invasive (nonnative) species • Population and resource use growth • Pollution • Climate change • Overexploitation
Case Study: A Disturbing Message from the Birds (1) • Habitat loss and fragmentation of the birds’ breeding habitats • Forests cleared for farms, lumber plantations, roads, and development • Intentional or accidental introduction of nonnative species • Eat the birds
Case Study: A Disturbing Message from the Birds (2) • Migrating birds fly into power lines, communication towers, and skyscrapers • Seabirds caught and drown in fishing equipment • Other threats • Oil spills • Pesticides • Herbicides • Ingestion of toxic lead shotgun pellets
Science Focus: Vultures, Wild Dogs, and Rabies: Unexpected Scientific Connections • Vultures poisoned from diclofenac in cow carcasses • Vultures died, dogs had less competition • More wild dogs eating the cow carcasses • More rabies spreading to people
Some Deliberately Introduced Species Can Disrupt Ecosystems • Most species introductions are beneficial • Food • Shelter • Medicine • Aesthetic enjoyment • Nonnative species may have no natural • Predators • Competitors • Parasites • Pathogens
KUDZU • Deliberately Introduced • Imported from Japan • Control soil erosion The vine that ate the South • Almost every part of the plant is edible • Leaves contain high levels of vitamins A and C
Argentina Fire Ant Accidentally Introduced into Mobile, Alabama, U.S.
Argentina Fire Ant • Accidentally introduced • Can wipe out as much as 90% of native ant population • Have killed deer fawn, birds, pets, even people
Burmese Python • Florida Everglades • Deliberately released from those who could not continue to have them as pets
Characteristics of Invader Species and Ecosystems Vulnerable to Invading Species
Case Study: Where Have All the Honeybees Gone? • Honeybees responsible for 80% of insect-pollinated plants • Dying due to? • Pesticides • Parasites • Bee colony collapse syndrome
Case Study: Polar Bears and Global Warming • Environmental impact on polar bears • Less summer sea ice • PCBs and DDT • 2007: Threatened species list
Illegal Killing, Capturing, and Selling of Wild Species Threatens Biodiversity • Poaching and smuggling of animals and plants • Animal parts • Pets • Plants for landscaping and enjoyment • Prevention: research and education
Rising Demand for Bush Meat Threatens Some African Species • Indigenous people sustained by bush meat • More hunters leading to local extinction of some wild animals
International Treaties Help to Protect Species • 1975: Convention on International Trade in Endangered Species (CITES) • Signed by 172 countries • Convention on Biological Diversity (BCD) • Focuses on ecosystems • Ratified by 190 countries (not the U.S.)
Case Study: The U.S. Endangered Species Act (1) • Endangered Species Act (ESA): 1973 and later amended in 1982, 1983, and 1985 • Identify and protect endangered species in the U.S. and abroad • Hot Spots • Habitat Conservation Plan (HCP) colony
Science Focus: Accomplishments of the Endangered Species Act (1) • Species listed only when serious danger of extinction • Takes decades for most species to become endangered or extinct • More than half of the species listed are stable or improving • Budget has been small
We Can Establish Wildlife Refuges and Other Protected Areas • 1903: Theodore Roosevelt • Wildlife refuges • Most are wetland sanctuaries • More needed for endangered plants • Could abandoned military lands be used for wildlife habitats?
Gene Banks, Botanical Gardens, and Wildlife Farms Can Help Protect Species • Gene or seed banks • Preserve genetic material of endangered plants • Botanical gardens and arboreta • Living plants • Farms to raise organisms for commercial sale