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Chapter 18: conservation of biodiversity. Sarah Blythe and Christina Reilly. Introduction: Modern conservation legacies. Decreasing biodiversity Sixth mass extinction Causes Human activity: habitat destruction, overharvesting Response Interest in conserving biodiversity Political effort
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Chapter 18: conservation of biodiversity Sarah Blythe and Christina Reilly
Introduction: Modern conservation legacies • Decreasing biodiversity • Sixth mass extinction • Causes • Human activity: habitat destruction, overharvesting • Response • Interest in conserving biodiversity • Political effort • Grant: Yellowstone National Park • Obama: Alaskan coastline critical habitat • Bush: Hawaiian marine habitats
Sixth mass extinction • Why should we care? • Instrumental and Intrinsic values • Extinction • Occurs when last member of a species dies • 50,000 extinction per year (.5% of world’s species) • First since humans have existed • Short amount of time
Global declines in genetic diversity of wild organisms • Conserving Genetic Diversity • Low population diversity • Not as well suited to change • Prone to inbreeding depression • Florida Panther, cheetah • Mutations more likely to spread
Global declines in the genetic diversity of livestock crops • Majority: Mammals and Birds • Donkeys, Buffalo, Cattle, Goats, Horses, Pigs, Sheep, Chicken, Ducks, Geese, Turkey • Trying to breed same traits for every animal, loss of genetic diversity • Endangered • Serious risk of extinction • 80% of domesticated animals either declining or facing extinction • Planting fewer varieties of crops leads to crop loss if environment changes • 1970’s- fungus kills half of corn fields in southern US • Solutions • Seed Storage Facilities (Svalbard Global Seed Vault)
Global declines in species diversity • International Union for Conservation of Nature (IUCN) • Classifications • Data deficient • Extinct • Threatened • Near-threatened • Least Concern • Estimated 10 million species on earth
Global declines in ecosystem function • Ecosystems provide valuable services • Lumber, food crops, prescription drugs • Pollinate crops, filter drinking water • Decline in species diversity associated with decline in ecosystems’ abilities to function • Millennium Ecosystem Assessment • 2006- 15 of 24 ecosystem functions in decline
Declining biodiversity has many causes • Causes • Habitat loss • Intrusion of alien species • Overharvesting • Pollution • Climate Change
Habitat loss • Causes • Human development • Deforestation • Species with narrow range of tolerance • More prone to population declines • Stats • 70% woodland/shrubland ecosystem bordering Mediterranean Sea has been lost • 50% grassland habitats lost • 30% desert habitats lost • Less than half of wetlands that existed in 1600’s • Only 10% live coral (2002) • Smaller habitat • Less genetic diversity • More interactions with predators • Restrict movement of migratory species
Alien species • Native species • live in historical range for thousands to millions of years • Alien/Exotic Species • live outside historical range • Animals, plants, or pathogens • Causes • Accidental Movement • Shipping containers (Madagascar) • Not all are threat to biodiversity • Invasive species • When alien species rapidly spread across large areas • No natural enemies • Solutions • Inspection of imported goods • Prohibition of untreated wooden packing crates
Overharvesting • Overharvesting • Individuals removed faster than can be replaced • Hunting, fishing, and poaching • Bison, passenger pigeon, dodo • Regulations • Restrict hunting and fishing of game animals at certain times of year • Limit number of animals to be harvested • Still illegal poaching of large fur animals
plant and animal trade • Trade is serious threat to ability to persist in nature • Regulation • Lacey Act 1900- prohibited transport of illegally harvested animals across state lines • Convention on International Trade in Endangered Species of wild Fauna and Flora (CITES) • IUCN
pollution • Toxic Contaminants • Pesticides, heavy metals, oil spills, and acids • BP • Endocrine Destruction • Prevent or inhibit reproduction, but not lethal • Eutrophication • Algal blooms • Thermal Pollution
Climate change • Affects temperature and precipitation • Some species not able to adapt to new conditions
The conservation of biodiversity often focuses on single species • One species at a time • When species is threatened or endangered • Try to improve conditions where it exists • Additional habitat • Reduce presence of contaminants • Captive Breeding (zoos) • Bred with intention of returning species to wild
Conservation Legislation • Marine Mammal Protection act 1972 • Prohibits killing of all marine mammals in US • Prohibits import/export of marine mammal body parts • Endangered Species act 1973 • Prohibits harming of threatened/endangered species • Allows government to purchase habitat critical to conservation of threatened/endangered species • Develop recovery plans to increase population • Controversy- restricts human activities in these areas; politicians try to weaken act
The convention on biological diversity • 1992- International treaty to help protect biodiversity • Objectives • Conserve biodiversity • Sustainably use biodiversity • Share benefits of commercial use of genetic resources • Identified Trends (2002-2010) • One quarter of plant species threatened with extinction • Natural habitats are smaller and more fragmented • Ecological footprint of humans has increased • Genetic diversity of crops and livestock still declining
The conservation of biodiversity sometimes focuses on protecting entire ecosystems • Reasons for Conservation • Aesthetic beauty • Communities of organisms • Amount of protected land has dramatically increased since 1960 • Factors to take into consideration • Size • Shape • Edge habitat: two different communities come together • Connectedness • Biosphere reserves • Protected areas with of zones that vary in amount of human impact • Preserves biodiversity without excluding all human activity • 464 in world
Working towards sustainability • Preserving biodiversity is expensive • Indirect costs (externalities) • Income loss from not using land/resources • Cost of maintaining protected area • Thomas Lovejoy (WWF) • Protect large areas of land & improve economic conditions of developing countries • Debtor nations can use position to motivate investment in biodiversity conservation • Debt transferred to environmental organizations • Helps protects country’s biodiversity • Conservation efforts in 3 main areas of land • Purchase of land • Prevention of illegal logging • Future grants to protect biodiversity