22 Sustaining Wild Species Miller’s - Living in the Environment 13 th Edition

Factors Affecting Biodiversity Factors that increase biodiversity 1)Physically diverse habitat 2)Moderate environmental disturbance 3)Small variation in environmental conditions 4)Middle stages of succession 5)Evolution Factors that decrease biodiversity 1) Environmental stress 2) Large environmental disturbance 3) Extreme environmental conditions 4) Severe limitations of an essential resource 5) Introduction of a non- native species 6) Geographic isolation

Measuring Biodiversity Biodiversity ~ variation among organisms – –Genetic Diversity (DNA combinations) – –Species Diversity – –Ecosystem Diversity Species Diversity Species Richness - # of total species present Species Evenness – number of different types of species Species Dominance – most abundant species present ** Describe this community in terms of species diversity using key terms from above. A  Richness = 100B  Richness = 100 Evenness = 10 Dominance = Elephant Dominance = All equal Less Diversity Greater Diversity How many species are present on Earth? ~ 1.5 million have been identified by biologists BUT estimates between million still remain

Describe this community in terms of species diversity using key terms. A  Richness = 25B  Richness = 25Evenness = 5 Dominance = circlecule Dominance = All equal Less Diversity Greater Diversity

Human Impacts on Biodiversity Fig p. 561

Species are …

Declining Biodiversity Extinction  death of species, irreversible loss, never to reappear ~ 34,000 currently near extinction Endangered  species in danger of extinction within range Usually exhibit specific characteristics as warning signs Threatened  low species population

Passenger pigeon Great auk Dodo Dusky seaside sparrow Aepyornis(Madagascar) Animal species that have become prematurely extinct

‘Endangered’ and ‘Threatened’ Species Endangered speciesEndangered species –species with so few individual survivors that the species could soon become extinct over all or most of its natural range. Florida manatee Northern spotted owl (threatened) Gray wolf Florida panther Bannerman's turaco (Africa) © 2004 Brooks/Cole-Thomson Learning

Endangered and Threatened Species Threatened (vulnerable) speciesThreatened (vulnerable) species –species that is still abundant in its natural range but because of declining numbers is likely to become endangered in the near future. Florida manatee Northern spotted owl (threatened) Gray wolf Florida panther Bannerman's turaco (Africa) © 2004 Brooks/Cole-Thomson Learning

What are some characteristics of extinction-prone species?

Characteristics of Endangered Species: What makes a species more vulnerable than others? small range large territory island living (isolated habitat) low reproductive fertility success need for specialized breeding areas need for specialized feeding habits habitat fragmentation Endemic – exclusive, not found anywhere else

CharacteristicExamples Low reproductive rate (K-strategist) Specialized niche Narrow distribution Feeds at high trophic level Fixed migratory patterns Rare Commercially valuable Large territories Blue whale, giant panda, rhinoceros Everglades kite Many island species, elephant seal, desert pupfish Bengal tiger, bald eagle, grizzly bear Blue whale, whooping crane, sea turtles Many island species, African violet, some orchids Snow leopard, tiger, elephant, rhinoceros, rare plants and birds California condor, grizzly bear, Florida panther

Effects of Human Activities on Extinction Rates Before humans, extinction rate was one species per million annuallyBefore humans, extinction rate was one species per million annually Current rate of extinction is estimated at 100 to 1000 times the rate before humansCurrent rate of extinction is estimated at 100 to 1000 times the rate before humans Speciation Crisis - limiting long-term recovery of biodiversity by reducing the rate of speciation for some types of species.Speciation Crisis - limiting long-term recovery of biodiversity by reducing the rate of speciation for some types of species.

Where is biodiversity declining? Tropical Rain Forests: being destroyed at faster rate than any other ecosystem for development and farmland cleared (slash/burn) for development due to deforestation

Why Should We Care About Biodiversity?  Instrumental value – their usefulness to us  Intrinsic value – they exist, regard-less of whether they have any usefulness to us

Pacific yew Taxus brevifolia Pacific Northwest Ovarian cancer taxol

Cinchona Cinchona ledogeriana South America Quinine for malaria treatment

Rosy periwinkle Cathranthus roseus native to Madagascar Hodgkin's disease, lymphocytic leukemia

Neem tree Azadirachta indica native to India Treatment of many diseases, insecticide, spermicide

What are human causes of endangerment? 1. Habitat loss -  range,  ability to survive 2. Invasive Species (Biotic Pollution) – –Non-native foreign species into ecosystem – –Problems with competition and predators – –Usually caused by humans EX. hyacinth, cane toads, zebra mussel, kudzu 3. Pollution- acid rain, ozone depletion, global warming, chemical runoff, acid mine drainage, thermal pollution

1. Habitat Fragmentation

HABITAT FRAGMENTATION Reduction in ranges of four wildlife species, mostly due to habitat loss and overharvest.Reduction in ranges of four wildlife species, mostly due to habitat loss and overharvest.

Range 100 years ago Indian Tiger Range today (about 2,300 left)

Overfishing Habitat loss Habitat degradation Introducing nonnative species Commercial hunting and poaching Sale of exotic pets and decorative plants Predator and pest control Pollution Climate change Basic Causes Population growthPopulation growth Rising resource useRising resource use No environmental accountingNo environmental accounting PovertyPoverty HIPPO

Range in 1700 Black Rhino Range today (about 3,600 left)

Probable range 1600 African Elephant Range today

(34,000–54,000 left) Asian or Indian Elephant Former range

Figure Page 574 Florida scrub jay Sprague’s pipitBichnell’s thrushBlacked-capped vireoGolden-cheeked warbler Cerulean warbler California gnatcatcherKirtland’s warblerHenslow’s sparrowBachman’s warbler Ten most threatened species of U.S. songbirds. Habitat loss and fragmentation most common threat.

Biome% of Area Disturbed Temperate broadleaf forests Temperate evergreen forests Temperate grasslands Mixed mountain systems Tropical dry forests Subtropical and temperate rain forests Cold deserts and semideserts Mixed island systems Warm deserts and semideserts Tropical humid forests Tropical grasslands Temperate boreal forests Tundra 94% 72% 71% 70% 67% 55% 53% 44% 37% 26% 18% 0.7%

2. Biotic Pollution After habitat loss and degradation, non-native species are the biggest cause of animal and plant extinctions.After habitat loss and degradation, non-native species are the biggest cause of animal and plant extinctions. Deliberately or accidentally introducedDeliberately or accidentally introduced

Type of Nonnative Organism Annual Losses and Damages Crop disease Crop weeds Rats Feral cats and outdoor pet cats Crop insects Livestock diseases Forest insects and diseases Zebra mussels Common pigeon Formosan termite Fishes Asian clam Feral pigs Starlings Fire ant $23.5 billion $23.4 billion $19 billion $17 billion $14 billion $9 billion $4.8 billion $3 billion $1.1 billion $0.8 billion $0.6 billion

Figure (1) Page 576 Purple loosestrifeEuropean starlingAfrican honeybee (“Killer bee”) NutriaSalt cedar (Tamarisk) Marine toadWater hyacinthJapanese beetleHydrillaEuropean wild boar (Feral pig) Deliberately Introduced Species

Figure (2) Page 576 Sea lamprey (attached to lake trout) Argentina fire antEurasian muffleBrown tree snakeCommon pigeon (Rock dove) Formosan termite Zebra mussel Asian long-horned beetle Asian tiger mosquito Gypsy moth larvae Accidentally Introduced Species

KudzuVine

INVASIVE SPECIES The Argentina fire ant was introduced to Mobile, Alabama in 1932 from South America.The Argentina fire ant was introduced to Mobile, Alabama in 1932 from South America. –Most probably from ships. –No natural predators.

Expansion of the fire ant in southern states.

4. Overexploitation – –species sometimes threatened due to deliberate efforts to control populations (ferrets, prairie dogs, “pests”) by hunters, gamers, farmers, ranchers – –unregulated hunting (bison, pigeon) – –poaching (Rhino, tiger, gorillas, leopards) for value on black market – –commercial harvest ~ collection of live organisms (pet trade) on black market What are human causes of endangerment?

Ivory

International trade in wild plants and animals Live mountain gorilla ($150,000)Live mountain gorilla ($150,000) Panda pelt ($100,000)Panda pelt ($100,000) Chimpanzee ($50,000)Chimpanzee ($50,000) Imperial Amazon Macaw ($30,000)Imperial Amazon Macaw ($30,000) Rhino horn ($13,000 per pound)Rhino horn ($13,000 per pound) As commercially valuable species become endangered, the black market demand soarsAs commercially valuable species become endangered, the black market demand soars

Other Extinction Threats Predators and Pest ControlPredators and Pest Control –Gray Wolf –Carolina parakeet –Prairie dog Market for Exotic Pets and Decorative PlantsMarket for Exotic Pets and Decorative Plants Climate ChangeClimate Change –Alters wildlife habitats –Not enough time to adapt

Protecting Diversity 1. HABITAT PROTECTION ~ most effective means - -conserving entire ecosystems - -wildlife refuge, sanctuaries, forests - 1 st Wildlife Refuge = 1903 Pelican Island, FL - -Conserve 10% of total land mass ?? Is this doable? 2. RESTORATION ~ returning degraded lands to prior state - -regenerates soil, rebuilds communities - very $$$, time consuming, usually forced through legislation 3. Zoos/Seed Banks - -deliberate reproduction to save species - -captive breeding necessary - seed storage for conservation of species

Relevant Legislation 1973 Endangered Species Act 1975 Convention on Int. Trade in End. Species (CITES) 1946 International Whaling Commission

Protecting Wild Species International Treaties –Convention on International Trade in Endangered Species (CITES) Forbids trade of 900 different live specimens or wildlife productsForbids trade of 900 different live specimens or wildlife products Restricts trade of 29,000 other threatened speciesRestricts trade of 29,000 other threatened species

Protecting Wild Species Legal ApproachLegal Approach –The Lacey Act of 1900 Prohibits movement of live or dead wild animals across state lines w/o a permitProhibits movement of live or dead wild animals across state lines w/o a permit –The Endangered Species Act of 1973 Illegal for Americans to import or trade in any product made from an endangered speciesIllegal for Americans to import or trade in any product made from an endangered species

Endangered Species Act National Marine Fisheries Service (NMFS)National Marine Fisheries Service (NMFS) –Identify and list endangered ocean species US Fish and Wildlife Service (USFWS)US Fish and Wildlife Service (USFWS) –Identify and list all other endangered or threatened species Species cannot be hunted, killed, collected, or injured in the USSpecies cannot be hunted, killed, collected, or injured in the US 1250 species listed today1250 species listed today Designate and protect the critical habitatDesignate and protect the critical habitat –Private lands subject to restrictions Prepare a recovery planPrepare a recovery plan

Concentration of rare species LowModerateHigh Top Six Hot Spots 1 Hawaii 2 San Francisco Bay area 3 Southern Appalachians 4 Death Valley 5 Southern California 6 Florida Panhandle

The U.S. has set aside 544 federal refuges for wildlife, but many refuges are suffering from environmental degradation.The U.S. has set aside 544 federal refuges for wildlife, but many refuges are suffering from environmental degradation. Pelican Island was the nation’s first wildlife refuge.

Gene banks, botanical gardens and using farms to raise threatened plant species can help prevent extinction, but these options lack funding and storage space.Gene banks, botanical gardens and using farms to raise threatened plant species can help prevent extinction, but these options lack funding and storage space. Zoos and aquariums can help protect endangered animal species by preserving some individuals with the long-term goal of reintroduction, but suffer from lack of space and money.Zoos and aquariums can help protect endangered animal species by preserving some individuals with the long-term goal of reintroduction, but suffer from lack of space and money. –captive breeding –cloning