Fig. 9-1, p. 176 Florida scrub jay Henslow's sparrow Bachman's warbler Black-capped vireo Kirtland's warbler Stepped Art
9-1 What Role Do Humans Play in the Premature Extinction of Species? Concept 9-1 The current rate of species extinction is at least 100 times the rate that existed before modern humans arrived on earth, and is expected to increase to between 1,000 and 10,000 times the earlier rate during this century.
Three Types of Extinction Local extinction Ecological extinction Biological extinction
Ecological Smoke Alarms Endangered species Threatened species The first to go large, slow, tasty, or have valuable parts Some behaviors make species prone to extinction
Calculating Extinction Rates Extinction takes a long time, difficult to document Only identified 1.8 million species – most unknown Know little of ecological role of most species Average species survive 1–10 million years Species-area relationship
Fig. 9-3a, p. 179 Siberian tiger Grizzly bear Kirkland’s warbler Knowlton cactus Florida manatee African elephant Utah prairie dog Swallowtail butterfly Humpback chub Golden lion tamarin
Fig. 9-3b, p. 179 Black rhinoceros Giant pandaBlack-footed ferret Whooping crane Northern spotted owl Blue whale Mountain gorillaFlorida panther California condor Hawksbill sea turtle
Human Activities and Extinction Background extinction rate Current rate is 100 times background extinction Rate likely to rise 1,000–10,000 times with climate change Is a mass extinction coming?
Fig. 9-5, p. 180 25% Fish Amphibians Mammals Reptiles Plants Birds 34% (51% of freshwater species) 32% 12% 14% 20%
Current Extinction Rate Estimates Are Conservative Species and biodiversity decrease in next 50– 100 years Biodiversity hotspot rates higher than global average Degrading, simplifying, and destroying diverse environments
9-2 Why Should We Care about Preventing Species Extinction? Concept 9-2 We should prevent the premature extinction of wild species because of the economic and ecological services they provide and because they have a right to exist regardless of their usefulness to us.
Value of Species Instrumental value of biodiversity Food crops Genetic information Medicine Do not know what we lose when species go extinct
Fig. 9-6, p. 181 Cathranthus roseus, Madagascar Hodgkin's disease, lymphocytic leukemia Rauvolfia Rauvolfia sepentina, Southeast Asia Anxiety, high blood pressure Foxglove Digitalis purpurea, Europe Digitalis for heart failure Pacific yew Taxus brevifolia, Pacific Northwest Ovarian cancer Cinchona Cinchona ledogeriana, South America Quinine for malaria treatment Neem tree Azadirachta indica, India Treatment of many diseases, insecticide, spermicide Rosy periwinkle
Values of Species Diversity Recreational pleasure value Eco-tourism >$500 billion per year Ethical obligations – intrinsic (existence) value Foundation of earth’s ecosystems bacteria and other microorganisms
9-3 How Do Humans Accelerate Species Extinction? Concept 9-3 The greatest threats to any species are (in order) loss or degradation of its habitat, harmful invasive species, human population growth, pollution, climate change, and overexploitation.
Underlying and Direct Causes of Depletion Fig. 9-7, p. 183
Secondary Causes of Endangerment and Premature Extinction (HIPPCO) (1) Habitat destruction Invasive species Population growth Pollution
Secondary Causes of Endangerment and Premature Extinction (HIPPCO) (2) Climate change Overexploitation
Habitat Loss Deforestation of tropical areas greatest eliminator of species Endemic species Habitat fragmentation
Fig. 9-9a, p. 185 European wild boar (Feral pig) Deliberately Introduced Species Purple loosestrifeEuropean starling African honeybee (“Killer bee”) Nutria Salt cedar (Tamarisk) Marine toad (Giant toad) Water hyacinth Japanese beetle Hydrilla
Fig. 9-9b, p. 185 Gypsy moth larvae Accidentally Introduced Species Sea lamprey (attached to lake trout) Argentina fire ant Brown tree snake Eurasian ruffe Common pigeon (Rock dove) Formosan termite Zebra mussel Asian long- horned beetle Asian tiger mosquito
Case Study: The Kudzu Vine Kudzu introduced to control erosion Prolific growth Uses Asians use powdered starch in beverages Source of tree-free paper Japanese kudzu farm in Alabama
DDT in water 0.000003 ppm, or 3 ppt DDT in fish-eating birds (ospreys) 25 ppm DDT in large fish (needle fish) 2 ppm DDT in small fish (minnows) 0.5 ppm DDT in zooplankton 0.04 ppm
Recovery Bald eagle recovered Factors leading to recovery Ban on DDT Crackdown on hunting Prevention of habitat destruction
Climate Change and Extinction More rapid compared to the past Expected to eliminate >25% of land animal and plant species Polar bears and penguins threatened
Illegal Killing and Trading of Wildlife Poaching endangers many larger animals, rare plants Over two-thirds die in transit Illegal trade $6–$10 billion per year Wild species depleted by pet trade Exotic plants often illegally gathered
White Rhinoceros Poached for Its Horn Fig. 9-15, p. 189
The Value of Wild Rare Species Declining populations increase black market values Rare species valuable in the wild – eco-tourism Some ex-poachers turn to eco-tourism
Rising Demand for Bush Meat Traditional use of bush meat Demand increasing with population growth Increased road access Loggers, miners, ranchers add to pressure Local and biological extinctions
9-4 How Can We Protect Wild Species from Premature Extinction? Concept 9-4A We can use existing environmental laws and treaties and work to enact new laws designed to prevent species extinction and to protect overall biodiversity. Concept 9-4B We can help prevent species extinction by creating and maintaining wildlife refuges, gene banks, botanical gardens, zoos, and aquariums.
International Treaties Convention on International Trade of Endangered Species (CITES) Convention on Biological Diversity (CBD)
Case Study: Controversy over the U.S. Endangered Species Act (1) National Marine Fisheries Services – ocean species U.S. Fish and Wildlife Service – other species Listings based on biological factors Forbids federal agency projects that jeopardize listed species or habitats
Case Study: Controversy over the U.S. Endangered Species Act (2) Fines violations on private land – 90% listed species on private land Illegal to sell or buy listed species 1,180 species listed USFWS and NMFS supposed to prepare recovery plan – 25% species have a plan
Case Study: Controversy over the U.S. Endangered Species Act (3) Successful recovery plans include American alligator and grey wolf Lax enforcement Smugglers not aware of dangerous diseases in exotic species Amended to give private landowners economic incentive to save species
Case Study: Controversy over the U.S. Endangered Species Act (4) ESA protect endangered marine reptiles and mammals Challenges to protecting marine species Limited knowledge of species Difficulty in monitoring and enforcing treaties – open oceans
Hawaiian Monk Seal with Plastic Debris Fig. 9-17, p. 192
Opposition to Endangered Species Act Opponents want: Voluntary protection on private land Government compensation for land owners Bureaucratic obstacles to listing species Elimination of need for critical habitat Exemptions granted by Secretary of Interior Steps to weaken ESA
New Ecosystems Approach Inventory country’s species and ecosystems Locate and protect the most endangered ecosystems Make development biodiversity-friendly through financial incentives and technical help
Science Focus: Accomplishments of the Endangered Species Act Biologists defend limited success Need more funding Develop recovery plans more quickly Core habitat established when listed
Establish Wildlife Refuges National Wildlife Refuge System Wetland refuges 35 million American visitors 20% of listed species in refuge system
Storing Genetic Information Gene or seed banks Botanical gardens Farms – commercial sale of endangered species removes pressure
Zoos and Aquariums for Protection Collect species with long-term goal of returning them into habitat 100–500 captive individuals to avoid extinction 10,000 individuals to maintain capacity for biological evolution
9-5 What Is Reconciliation Ecology? Concept 9-5 We can help protect some species from premature extinction by finding ways to share the places we dominate with them.
Reconciliation Ecology Danger that biodiversity preserve efforts will fail Develop reconciliation ecology
Case Study: The Blackfoot Challenge (1) Blackfoot River – large Montana watershed 600 plant and 21 large animal species Seven human communities, 2,500 rural households Community established Action Team
Case Study: The Blackfoot Challenge (2) Developed Restoration, sustainable grazing, conservation easement plans Created corridor between undeveloped lands Restored wetlands, streams
Animation: Species Diversity By Latitude PLAY ANIMATION
Animation: Area and Distance Effects PLAY ANIMATION
Animation: Humans Affect Biodiversity PLAY ANIMATION
Animation: Resources Depletion and Degradation PLAY ANIMATION
Animation: Biodiversity Hot Spots PLAY ANIMATION
Animation: Habitat Loss and Fragmentation PLAY ANIMATION
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