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AP Environmental Mrs. Dow Chapter 12. Species extinction 12.1. 1. Local Species disappears from an area, found elsewhere 2. Ecological # of species is low, cannot fulfill role 3. Biological Species disappeared from earth. Lost Natural Capital. Passenger pigeon. Dusky seaside sparrow.
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Species extinction 12.1 1. Local • Species disappears from an area, found elsewhere 2. Ecological • # of species is low, cannot fulfill role 3. Biological • Species disappeared from earth
Lost Natural Capital Passenger pigeon Dusky seaside sparrow Great auk Dodo Aepyornis (Madagascar)
Figure 12-3aPage 226 Kirtland's warbler White top pitcher plant Grizzly bear (threatened) Arabian oryx (Middle East) African elephant (Africa) Mojave desert tortoise (threatened) Swallowtail butterfly Humpback chub Golden lion tamarin (Brazil) Siberian tiger (Siberia) Endangered Natural Capital
Figure 12-3b Page 226 Whooping crane West Virginia spring salamander Knowlton cactus Giant panda (China) Blue whale Pine barrens tree frog (male) Swamp pink Hawksbill sea turtle El Segundo blue butterfly Mountain gorilla (Africa) Endangered Natural Capital
Figure 12-3c Page 227 Florida manatee Northern spotted owl (threatened) Bannerman's turaco (Africa) Gray wolf Florida panther Devil's hole pupfish Black-footedferret Snow leopard (Central Asia) Utah prairie dog (threatened) Symphonia (Madagascar) California condor Black lace cactus Oahu tree snail Ghost bat (Australia) Black rhinoceros (Africa)
Characteristic Examples Low reproductive rate (K-strategist) Blue whale, giant panda, rhinoceros Specialized niche Blue whale, giant panda, Everglades kite Narrow distribution Many island species, elephant seal, desert pupfish Bengal tiger, bald eagle, grizzly bear Feeds at high trophic level Fixed migratory patterns Blue whale, whooping crane, sea turtles Rare Many island species, African violet, some orchids Commercially valuable Snow leopard, tiger, elephant, rhinoceros, rare plants and birds Large territories California condor, grizzly bear, Florida panther
Going toward bio extinction • Endangered • Too few in # • Soon to be extinct • 1st to go . . . • Big, slow, tasty, valuable • Passenger pigeon • Overhunting; habitat destruction • ~21K species in U.S.
34% (51% of freshwater species) Fish 24% Mammals 20% Reptiles 14% Plants 12% Birds
Greater extinction rates due to: • Biodiversity loss due to exponential growth • “Hot spots” cause concern • Colonization sites are being eliminated
Importance of wild species 12.2 • Speciation is being reduced • Medicinal properties • Genetic info from animals of value • Recreational value • Eco-tourism generates monies • All species have important roles in keeping environment balanced
Range 100 years ago Range today (about 2,300 left) Indian Tiger
Range in 1700 Range today (about 2,400 left) Black Rhino
Probable range 1600 Range today (300,000 left) African Elephant
Figure 12-7dPage 232 Former range Range today (34,000–54,000 left) Asian or Indian Elephant
Extinction Threats 12.3 • Deforestation, loss of wetlands • Largest threat in tropical forests • Major habitat disturbances 1. Agriculture 2. Commercial development 3. Water development 4. Outdoor recreation 5. Livestock grazing 6. Pollution
Endemic species • Found nowhere else on Earth • Often on islands • Habitat islands • Habitat surrounded by different one
Figure 12-8Page 233 Cerulean warbler Sprague’s pipit Bichnell’s thrush Blacked-capped vireo Golden-cheeked warbler Florida scrub jay California gnatcatcher Kirtland’s warbler Henslow’s sparrow Bachman’s warbler Ten Most Threatened species of U. S. songbirds
Habitat fragmentation • Leads to species vulnerability, disease • 1:6 birds are threatened • Birds excellent indicator; strong environmental roles • Nonnative species big threat to birds
Figure 12-9aPage 235 Purple looselife European starling African honeybee (“Killer bee”) Nutria Salt cedar (Tamarisk) Marine toad Water hyacinth Japanese beetle Hydrilla European wild boar (Feral pig) Deliberately introduced Species
2 4 3 5 Top Six Hot Spots 6 1 Hawaii 2 San Francisco Bay area 3 Southern Appalachians 4 Death Valley 5 Southern California 6 Florida Panhandle Concentration of rare species 1 Low Moderate High
Figure 12-9b Page 235 Sea lamprey (attached to lake trout) Argentina fire ant Brown tree snake Eurasian muffle Common pigeon (Rock dove) Formosan termite Zebra mussel Asian long-horned beetle Asian tiger mosquito Gypsy moth larvae Accidentally introduced Species
Argentina Fire Ant 1918 2000
Extinction Threats from Nonnative species 12.4 • May replace native • Disrupt ecosystems • Large economic loss
Characteristics of Successful Invader Species Characteristics of Ecosystems Vulnerable to Invader Species • High reproductive rate, short generation time (r-selected species) • Pioneer species • Long lived • High dispersal rate • Release growth- inhibiting chemicals into soil • Generalists • High genetic variability • Similar climate to habitat of invader • Absence of predators on invading species • Early successional systems • Low diversity of native species • Absence of fire • Disturbed by human activities
Alien may be intro accidentally or deliberately • Threaten native species • No natural predators, competitors, pathogens • Feral cats kill 568 million birds/yr
Controlling nonnative species • Stop from being introduced (best) • Inspect imported goods • Prevent transfer w/international laws
Deer populations • Exploded in suburbs • Edge species • Kill more people in U.S. than any other animal • No good resolution • Birth control? Sharp shooters?
2/3 live animals die in transit • Tiger populations low; killed for fur • Black market demand increases w/endangered label
Extinction threats from poaching & hunting 12.5 • Killed for valuable parts • Sold live • Very profitable
Indigenous people eat local animals • 8x increase in pop • Logging roads • Restaurants serve tropical animals • Less seed-dispersing animals
Other extinction threats 12.6 • Gvt kills coyotes, prairie dogs, wolves, bobcats (all prey on livestock) • 99% of prairie dogs have been eradicated • Black-footed ferret preyed on prairie dog
Global trade • Parrots • Amphibians • Reptiles • Mammals • Tropical fish • Ex-poachers in Thailand make more money with eco-tourism
Pollution • Climate change • Global warming alters habitats • Animals cannot adapt fast enough
North American-South American flyways European-African flyways Asian flyways
Protecting wild species 12.7 • 1975 Convention on International Trade in Endangered Species (CITES) • Protects 900 species from being traded & restricts 29K that may become threatened • Some countries to not abide
Lacey Act of 1900 • Prohibits transporting live or dead wild animals w/o federal permit
Endangered Species Act of 1973 (ESA) • Identified & illegally protects endangered species in U.S. & abroad • National Marine Fisheries, U.S. Fish & Wildlife Service identify & list • Political pressure & lack of money limit ESA • (2003) DOD is exempted from protection lists
(1999) USFWS • Safe harbor agreement • Landowners voluntarily restore, improve habitat
Many want ESA weakened • National Academy of Science/biologists • Increase funding • Recovery plans • Support endangered for up to 50 years • Identify critical habitats • Incentives to those who protect
Protecting Wild Species 12.8 • Sanctuary approach • 542 federal refuges • 1/5 of U.S. endangered & threatened species • Zoos & aquariums • Egg pulling • Captive breeding • Artificial insemination
Reintroducing species into wild • Not enough suitable land • Breed in captivity not able to survive in wild • Renewed overhunting of returned species • 10,000+ need to continue evolution
Reconciliation ecology 12.9 • Learn to share spaces we dominate • Utilize native plants to attract animals • Bio-diverse yards • Rooftop gardens Government land, college campuses, schools used for laboratories
What Can You Do? Protecting Species • Do not buy furs, ivory products, and other materials made from endangered or threatened animal species. • Do not buy wood and paper products produced by cutting remaining old-growth forests in the tropics. • Do not buy birds, snakes, turtles, tropical fish, and other animals that are taken from the wild. • Do not buy orchids, cacti, and other plants that are taken from the wild.