1 Biological Resources Chapter 15

2 Disappearing Frogs 168 amphibian species are though to have become extinct in the last 2 decades About 1/3 of all amphibian species are threatened No single cause of massive die-offs Habitat loss, Chemical pollutants, Infectious diseases, UV radiation, Climate change are all suspects Chytridiomycosis, rapidly spreading fungal disease has been found in 43 countries and 36 US states, exacerbates harm form other causes

3 Species Richness and Biological DiversityLearning Objectives: Describe factors associated with species richness Define biological diversity and distinguish among species richness, genetic diversity, and ecosystem diversity Relate several important ecosystem services provided by biological diversity

4 Species Richness and Biological DiversityA group of distinct organisms that are capable of interbreeding with one another in the wild but that do not interbreed with organisms outside their group How many species? 5–100 million species total estimate 10,000 new species identified per year

5 Species Richness and Biological DiversityThe number of different species in a community. Varies form community to community Related to the abundance of potential niches Inversely related to isolation of community Species have difficulty reaching and colonizing isolated places (e.g., islands) Locally extinct species are not replaced quickly Inversely related to environmental stress Usually greater at the edges of adjacent communities than at the center of a community Ecotone: a transitional zone where communities meet Edge effect: change in species composition that occurs at ecotones

6 Species Richness and Biological Diversity

7 Species Richness and Biological DiversityWhy We Need Biodiversity The number and variety of Earth’s organisms; 3 components: Genetic diversity Species richness Ecosystem diversity Humans depend on thousands of species for survival Insects for pollination, weed control, pest control Bacteria and fungi for food, antibiotics, medicines 288,000 out of 330,000 plant species have not been assessed for medicinal, agricultural, or industrial value

8 Species Richness and Biological Diversity

9 Species Richness and Biological DiversityEcosystem Services and Species Richness The activities of all organisms in an ecosystem are interrelated. When one species declines, other species linked to it may either decline or increase in number Ecosystem Services Environmental benefits, such as clean air, clean water, and fertile soil, provided by an ecosystem

10 Species Richness and Biological Diversity

11 Species Richness and Biological Diversity

12 Species Richness and Biological DiversityImportance of Genetic Diversity Evolution has taken hundreds of millions of years to produce genetic diversity we see today Diversity may hold solutions to today’s problems and to problems we have not begun to imagine Genetic engineering uses gene diversity Variation in wild relatives of crops allows us to introduce variation and resistance to diseases

13 Species Richness and Biological DiversityMedicinal, Agricultural, and Industrial Importance of Organisms Genetic resources of organisms are important to pharmaceutical industry AIDS medication AZT is a derivative of a compound extracted from sponges 20 best-selling prescription drugs in US are natural products slightly modified or synthetic chemicals derived from organisms Agricultural importance is obvious We must eat to survive Modern Industrial Technology Oils, lubricants, perfumes, fragrances, dyes, paper, lumber, waxes, latex,

14 Species Richness and Biological Diversity

15 Species Richness and Biological DiversityAesthetic, Ethical, Spiritual Value of Organisms Recreation, inspiration, spiritual solace Our world is a thing of beauty largely because of the diversity of living forms in it

16 Global Climate Change What are two determinants of species richness? Give an example of each What is biological diversity? What are ecosystem services? Describe some ecosystem services that a forest provides

17 Endangered and Extinct SpeciesLearning Objectives Define extinction and distinguish between background extinction and mass extinction Contrast threatened and endangered species Describe four human causes of species endangerment and extinction

18 Endangered and Extinct SpeciesExtinction The elimination of a species from Earth Natural part of life. Background extinction Continuous low level of extinction of species Mass extinction Large number of species disappear during a relatively short period of geologic time Although natural process, it can be greatly accelerated by human activities Human population growth has disrupted habitats Biodiversity is disappearing at an unprecedented rate 100 to 1000 times the natural rate of background extinction

19 Endangered and Extinct Species

20 Endangered and Extinct SpeciesEndangered and Threatened Species Endangered Species Act legally defines Endangered species A species is in imminent danger of extinction throughout all or a significant portion of its range Threatened species A species whose population has declined to the point that it may be at risk of extinction Represent a decline in biological diversity because as their numbers decrease their genetic variability is severely diminished Lower genetic diversity is heightens the risk of extinction

21 Endangered and Extinct SpeciesAreas of Declining Biological Diversity A concern throughout the US, but mostly Hawaii (63% of species are at risk), 2/3 of native forests are gone California (29% of species at risk) Very serious concern in tropical rain forests Being destroyed for human settlements, banana plantations, oil and mineral exploration, etc. Home to thousands or millions of species Many species are endemic (native to/confined to a particular region), not found anywhere else in the world Deforestation affects evolution

22 EnviroDiscovery Is Your Coffee Bird Friendly?Many species of migratory songbirds are in decline American’s coffee habits may play a role Sun plantations (growing coffee in full sunlight) are becoming more common High-input, outproduce shade plantations Lots of chemical fertilizers and pesticides 94–97 fewer species of birds Shade plantations (traditional) are more environmentally friendly do not require cutting rain forest Support populations of songbirds Provides variety of forest products Often organic and handpicked

23 EnviroDiscovery

24 Endangered and Extinct SpeciesEarth’s Biodiversity Hotspots Relatively small areas of land that contain an exceptional number of endemic species and are at high risk from human activities 25 hotspots for plant species contain 29% of world’s endemic species, 27% of endemic mammal species, 38% of endemic reptile species, 53% of endemic amphibian species. 20% of the world’s human population lives in hotspots 15 hotspots are tropical, 9 are mostly/solely islands

25 What a Scientist Sees

26 Endangered and Extinct SpeciesHuman Causes of Species Endangerment Loss of habitat is greatest threat Pollution Spread of invasive species Overexploitation All this is caused by Growth of human populations Economic activity Uses of technology Social, political, cultural factors

27 Environmental InSight

28 Environmental InSight28

29 Endangered and Extinct SpeciesHabitat Fragmentation The breakup of large areas of habitat into small, isolated patches (islands) Pollution Acid precipitation, stratospheric ozone depletion, climate warming degrade even wilderness habitats that are otherwise undisturbed Invasive Species Foreign species that spread rapidly in a new area if free of predators, parasites, or resource limitations that may have controlled their population in their native habitat

30 Endangered and Extinct Species

31 Endangered and Extinct SpeciesInvasive Species Introduction of non-native species into an ecosystem where it did not evolve often upset the balance among the organisms living in that area and interferes with the ecosystem’s normal functioning Maybe introduced by natural means, but in most cases is by human activity, intentionally or non-intentionally Ballast water in cargo-carrying ships  zebra mussel Economic losses and control efforts cost the US about $5 billion/yr

32 Endangered and Extinct Species

33 Endangered and Extinct SpeciesOverexploitation Sometimes species become endangered or extinct as a result of deliberate efforts to eradicate or control their numbers Ranchers, hunters, governments, farmers Unregulated hunting or overhunting Illegal hunting/Poaching Commercial harvest

34 Endangered and Extinct Species

35 Global Climate Change What is background extinction? Mass extinction?What is the difference between a threatened species and an endangered species? How do human activities cause species to become endangered or extinct?

36 Conservation Biology Learning Objectives:Define conservation biology and compare in situ and ex situ conservation Describe restoration ecology

37 Conservation Biology The scientific study of how humans affect organisms and of the development of ways to protect biological diversity In situ-’in place’ Includes establishment of parks and reserves, concentrates on preserving biological diversity in nature. Ex situ- ‘outside its place’ Involves preserving biodiversity in human controlled settings: zoos, botanical gardens, seed banks of genetically diverse plant crops

38 Conservation Biology Protecting HabitatsConserving and managing the ecosystem as a whole is the best way to preserve biodiversity Human activities adversely affect sustainability, so active management is required 3500 national parks, preserves, etc. exist worldwide-not always effective in preservation Too small, too isolated Little money/expertise to manage them Most preserves are in areas of low diversity Urgently needed in tropical rain forests, tropical grasslands and savannas, dry forests, river basins

39 Conservation Biology

40 Conservation Biology Wildlife RefugesNational Wildlife Refuge System-1903 Most extensive network of lands and waters committed to wildlife preservation in the world 545 refuges, at least 1 per state Represent all major US ecosystems

41 Conservation Biology

42 Conservation Biology Restoring Damaged or Destroyed HabitatsRestoration Ecology: the study of the historical condition of a human-damaged ecosystem, with the goal of returning it as closely as possible to its former state Reclaim disturbed lands and convert them into areas with high biodiversity, using ecological principles, to return them to a functional and sustainable ecosystem Creates habitats, regenerates soil, Requires time and expense Important component of in situ conservation

43 Conservation Biology Conserving SpeciesConservation organizations are essential part of the effort to maintain biodiversity. Educate policymakers, galvanize public support, provide financial supports for projects Work in conjunction with zoos, aquaria, botanical gardens, etc.

44 Conservation Biology Methods and Goals:Reintroduction of endangered species Captive-breeding programs Seed Banks (gene banks) Worldwide, hold millions of seed samples at low temperatures, in small space Seeds are safe from habitat destruction, climate change, neglect Have been used to reintroduce extinct species Some seeds cannot be stored Seeds must be grown up and more collected, due to longevity issues, are not continuously exposed to environment  evolutionary implications 44

45 Environmental InSight

46 Global Climate Change What is conservation biology and when is in situ conservation used? Ex situ? What are the goals of restoration ecology?

47 Conservation Policies and LawsLearning Objectives: Describe the benefits and shortcomings of the US Endangered Species Act? Relate the purpose of the World Conservation Strategy.

48 Conservation Policies and LawsEndangered Species Act-1973 Authorizes FWS to protect endangered and threatened species in the US and abroad Currently 1300 species are listed-have legal protection Requires FWS to select critical habitats and design detailed recovery plan, including Current population size, reasons for it being endangered, actions to help recovery ESA updated in 1980, 1985, 1988 Very controversial legislation, entangled in political wrangling Should be strengthened to manage entire ecosystems, rather than individual species

49 Conservation Policies and Laws

50 Conservation Policies and Laws

51 Conservation Policies and LawsInternational Policies and Laws World Conservation Strategy Plan to preserve biodiversity and essential ecosystem services on which all life depends for survival Earth Summit Each signatory nation (193) must inventory its biodiversity and develop a national conservation strategy CITES Bans the hunting, capturing, and selling of endangered and threatened species Protects about 30,000 species Enforcement varies from country to country-penalties are not severe enough Illegal trade continues Who Owns world’s biodiversity?

52 Conservation Policies and Laws

53 Global Climate Change What are the goals of the Endangered Species Act and why is the ESA considered controversial? What is the World Conservation Strategy?

54 Case Study Fighting the Asian Carp InvasionTwo species of Asian carp introduced into southern US as aquaculture species ‘escaped’ into natural environment in 1990s during floods Fast growing filter feeders, no known predators Could disturb food chain of native species in Great Lakes, and ruin commercial fisheries Illinois sought emergency closing of canals to prevent entrance of carp into the Great Lakes Rejected due to the interests of the shipping industry in the area

55 Case Study