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Texas Natural Regions. Extinction Rates. Geological Periods. Carboniferous. Cretaceous. Devonian. Jurassic. Silurian. Triassic. Tertiary. Ordovician. Permian. Quaternary. Cambrian. Mass extinctions. 800. 600. ?. 400. 200. 0. 570. 505. 438. 360. 286. 208. 144. 65. 0.
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Extinction Rates Geological Periods Carboniferous Cretaceous Devonian Jurassic Silurian Triassic Tertiary Ordovician Permian Quaternary Cambrian Mass extinctions 800 600 ? 400 200 0 570 505 438 360 286 208 144 65 0 408 245 2 Millions of years ago • Background (natural) rate of extinction • Massextinction Number of families of marine animals • Adaptiveradiations
Sustaining Wild Species Brian Kaestner and Dr. Richard Clements Saint Mary’s Hall and Chattanooga State Technical Community College
Why Should We Care About Biodiversity? Value of Nature Instrumental Intrinsic (human centered) (species or ecosystem centered) Nonutilitarian Utilitarian Goods Existence Ecological services Aesthetic Information Bequest Option Recreation • Instrumental value • Intrinsic value
Arctic Circle Arctic Circle 60° EUROPE NORTH AMERICA ASIA 30°N Tropic Of Cancer Atlantic Ocean AFRICA Pacific Ocean Pacific Ocean 0° 150° 120° 90° 30°W 0° 60°E 90° 150° SOUTH AMERICA Indian Ocean Tropic Of Capricorn AUSTRALIA 30°S Antarctic Circle 60° ANTARCTICA Critical and endangered Threatened Stable or intact Projected Status of Biodiversity 1998–2018
Human Impacts on Biodiversity Changes in water supply and temperature Deforestation Changes in water supply and temperature Deforestation Water use and pollution and soil nutrient loss Freshwater supply and demand Food supply and demand Water availability Changes in precipitation and temperature Erosion, pollution, and changes in water flow CO2, CH4, N2O emissions Habitat change and fragmentation of habitat Forest product supply and demand Loss and fragmentation of habitat Loss and fragmentation of habitat Climate change CO2 emission Changes in transpiration and albedo Loss and fragmentation of habitat Loss of crop genetic diversity Habitat change Reduced resistance to change Biodiversity loss
Decreasing Biodiversity • Large environmental disturbance • Introduction of alien species • Geographic isolation
Biome % of Area Disturbed Temperate broadleaf forests 94% Temperate evergreen forests 94% Temperate grasslands 72% Mixed mountain systems 71% Tropical dry forests 70% Subtropical and temperate rain forests 67% Cold deserts and semidesert 55% Mixed island systems 53% Warm deserts and semideserts 44% Tropical humid forests 37% Tropical grasslands 26% Temperate Boreal forests 18% Tundra 0.7%
Increasing Biodiversity • Physically diverse habitat • Moderate environmental disturbance
US Diversity 1% Probably extinct 7% Critically imperiled 67% Secure or apparently secure 8% Imperiled 16% Vulnerable 1% Other
Species Extinction • Local extinction • Ecological extinction • Biological extinction
Endangered and Threatened Species Florida manatee Northern spotted owl (threatened) Gray wolf Florida panther Bannerman's turaco (Africa) • Endangered species • Threatened (vulnerable) species • Rare species
Badger Anemone
Karner Blue Hawaian Sea Turtle
Ceratozamia Whooping Crane
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
Range 100 years ago Range today (about 2,300 left) Indian Tiger
Range in 1700 Range today (about 2,400 left) Black Rhino
Causes of Premature Extinction of Wild Species Habitat loss Habitat degradation Overfishing Basic Causes Introducing nonnative species Climate change • Population growth • Rising resource use • No environmental accounting • Poverty Commercial hunting and poaching Pollution Sale of exotic pets and decorative plants Predator and pest control • Habitat degradation • Introduction of non-native species
Type of Nonnative Organism Annual Losses and damages Crop disease $23.5 billion Crop weeds $23.5 billion Rats $19 billion Feral cats and outdoor pet cats $17 billion Crop insects $14 billion Livestock diseases $9 billion Forest insects and diseases $4.8 billion Zebra mussels $3 billion Common pigeon $1.1 billion Formosan termite $1.1 billion Fishes $1.1 billion Asian clam $1.1 billion Feral pigs $0.8 billion Starlings $0.8 billion Fire ant $0.6 billion
1918 2000 Expansion of the fire ant in southern states.
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 species • Low diversity of native species • Absence of fire • Disturbed by human activities
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
Wildlife Management • Laws regulating hunting and fishing • Harvest quotas • Population management plants • Improving habitat • Treaties and laws for migrating species
Solutions: Protecting Wild Species from Depletion and Extinction • Bioinformatics • International Treaties: CITES • National Laws: Lacey Act Endangered Species Act • Habitat conservation plans • Wildlife refuges and protected areas • Zoos, botanical gardens, and gene banks
Strategies for Protecting Biodiversity The Species Approach The Ecosystem Approach Goal Goal Protect populations of species in their natural habitats Protect species from premature extinction Strategies Strategy • Identify endangered species • Protect their critical habitats Preserve sufficient areas of habitats in different biomes and aquatic systems Tactics Tactics • Protect habitat areas through private purchase or government action • Eliminate or reduce populations of alien species from protected areas • Manage protected areas to sustain native species • Restore degraded ecosystems • Legally protect endangered species • Manage habitat • Propagate endangered species in captivity • Reintroduce species into suitable habitats • Species approach • Ecosystem approach