Presentation on theme: "Chapter 12: Sustaining biodiversity (species/extinction)"— Presentation transcript:
1Chapter 12: Sustaining biodiversity (species/extinction) Land and Water Use Unit
2Types of ExtinctionLocal extinction: better known as extirpation. A species is no longer found in an area it used to inhabit, but can be found elsewhere.Ecological extinction: too few members of that species exist in an area to continue to play their role in the ecology of an area (predator, prey, etc.)Biological extinction: true extinction. No members of that species exist on Earth. Example: dinosaurs, passenger pigeon
3Remember these?Background extinction: “Normal” extinction that occurs at a low rate: 1-5 species per million. May be due to evolution…Mass extinction: Extremely high rates of extinction. There have been 5 mass extinctions and we may be in a possible 6th mass extinction.Reread 6th extinction from Ch. 1 internet activity for homework.
4Who’re you calling threatened? Endangered species: Numbers are so low that the species could soon become extinct. Protected by law. (Endangered Species Act of 1973)Threatened species: Numbers are low enough that species could soon become threatened. Protected by law.Special concern: Animals that are suspected to be experiencing problems, but no documentation has been made. Not protected by law.
5Fixed migratory patterns Commercially valuable CharacteristicExamplesWhat puts them at risk?Low reproductive rate(K-strategist)Blue whale, giant panda,rhinocerosSpecialized nicheBlue whale, giant panda,Everglades kiteNarrow distributionMany island species,elephant seal, desert pupfishBengal tiger, bald eagle,grizzly bearFeeds at high trophiclevelFixed migratory patternsBlue whale, whooping crane,sea turtlesRareMany island species,African violet, some orchidsCommercially valuableSnow leopard, tiger,elephant, rhinoceros,rare plants and birdsLarge territoriesCalifornia condor, grizzlybear, Florida panther
6Percentage of threatened/ endangered 34% (51% of freshwater species)Fish24%Mammals20%ReptilesPercentage of threatened/ endangered14%PlantsBirds12%
7Indian Tiger Range 100 years ago Range today (about 2,300 left)
8Black RhinoRange in 1700Range today(about 2,400 left)Black Rhino
9African Elephant Probable range 1600 Range today (300,000 left)
10Asian or Indian Elephant Figure 12-7d Page 232Asian ElephantFormer rangeRange today(34,000–54,000 left)Asian or Indian Elephant
11Maintenance through Conservation Maintaining and protecting wildlife consists of 3 major approaches:Species approach – protecting endangered species though legislation.Ecosystem approach – persevering balanced ecosystems
12Maintenance through Conservation 3. Wildlife management approach – managing game species for sustained yield through interaction treaties to protect migration species, improving wild life habitats, regulating hunting and fishing, creating harvest quotas and developing population management plans.
13Why should we care??? Instrumental value Gene pool/genetic information (useful for vaccines, resistance)Wildlife tourism (existential value)Recreational pleasurePlace in ecosystem (pollinator, keystone, indicator, etc)“It’s like burning books before you read them.”
14Causes of endangerment Habitat destruction (for resources, farmland, residential, pollution)Introduction of alien/non-native/invasive speciesOverexploitation (over-harvested, over-hunted, poaching)DiseasePollutionInterrupted migration
15Oops – I did it again Introduced on purpose: Kudzu vine (prevent erosion )House sparrow (eat cankerworms -1950)Carp (“world’s finest fish” )Nutria (fur)Ring-neck pheasant (hunting -1881)
20Accidentally introduced Species Figure 12-9b Page 235Sea lamprey(attached to lake trout)Argentina fire antBrown tree snakeEurasian muffleCommon pigeon(Rock dove)Formosan termiteZebra musselAsian long-hornedbeetleAsian tiger mosquitoGypsy moth larvaeAccidentally introduced Species
21Argentina Fire Ant Distribution 19182000Argentina Fire Ant Distribution
22Ecosystems Vulnerable Characteristics ofSuccessfulInvader SpeciesCharacteristics ofEcosystems Vulnerableto Invader SpeciesHigh reproductive rate, short generation time (r-selected species)Pioneer speciesLong livedHigh dispersal rateRelease growth- inhibiting chemicals into soilGeneralistsHigh genetic variabilitySimilar climate to habitat of invaderAbsence of predators on invading speciesEarly successional systemsLow diversity of native speciesAbsence of fireDisturbed by human activitiesWill we be invaded?
23It’s the law…CITES: Convention on International Trade in Endangered Species: 1975, treaty signed by 160 countries, lists 900 species that cannot be traded either alive or as products.CBD: Convention on Biological Diversity. Signed by 186 countries legally binds governments of signing countries to attempt to reverse the loss of biological diversity. Each country forms a national conservation plan.Lacey Act of 1900: US act, can’t transport live or dead wild animals or parts of them across state borders without permitsEndangered Species Act: Amended in 1982, 85, 88. Identifies animals as threatened or endangered and protects them by law.
24Zoos or Not?Read pagesUtilize the internet for additional support for your essay.Essay – should be 3-4 paragraphs on whether or not zoos/aquariums/captivity programs should be utilized for endangered/threatened species (with no intention of releasing to the wild)