Carolina Parakeet. Tasmanian Tiger. Gastric brooding frog. Panthera leo barbaricus Barbary Lion. Aldabra tortoise. Seychelle saddleback

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1 Carolina Parakeet Panthera leo barbaricus Barbary Lion extinct around 1935? (1918?) Extinct 19 Tasmanian Tiger Gastric brooding frog Extinct 1936 Extinct? Not found since 1985 Table.. A sample of once thought extinct, but rediscovered. Species name Common name Date rediscovered # yrs since last sighting Dipsochelys hololissa Seychelles giant tortoise 1997 >15 Aldabra tortoise Pterodroma cahow Bermuda petrel 1951 > Perameles bougainville Western barred bicoot Trichocichla rufa Long-legged warbler 3 9 Gastrolobium lehmannii Cranbrook pea 1 83 Hapalopsittaca fuertesi Fuertes's parrot 91 Hypsiprimnus gilbertii Gilbert s potoroo Sida inflexa Virginia pine sida Lepidoptrix (formerly Pipra) vilaboasi Golden crowned manakin 45 Seychelle tortoise Seychelle saddleback

2 Measuring Current Extinctions Direct observation are difficult Indirect observation: - area relationship Species-Area relationship Species-Area relationship Number of S S = c A z c is a taxon specific constant z is the extinction coefficient is in the range.1 to.3 log(number of S) S = c A z c is a taxon specific constant z is estimated using the slope Area A log(area A) Mac Arthur Wilson (1967): the theory of isl biogeography Fig 4.5 Small mammals in forest granivores all small mammals r = proportion of variation explained

3 Estimating extinction rates Estimating how many go extinct Log(Number of S) S now S original = Az now A z original Log(Number of S) Log(Area A) S now = S original A z now A z original Log(Area A) S now S original = caz now ca z original using z=.15 (this is arbitrary) deforestation = 1.8% per year (A now / A original = 98./) million (S original ) S now = 9,973, Difference between S now S original = 7, per year? Percent of affected Percent of affected habitat loss (less area = fewer )

4 habitat loss (less area = fewer ) habitat fragmentation Fringed prairie orchid Fig 55.6 Forest cover of Cadiz Township in Wisconsin habitat loss (less area = fewer ) habitat fragmentation Edge effects Fragmentation Fig 4.5 Small mammals in forest granivores all small mammals r = proportion of variation explained

5 loss (less area = fewer ) fragmentation Edge effects Isolation Percent of affected : introduced to regions outside of their native range Invasive : an exotic with strongly increasing populations ( most often detrimental effect on the native or habitats) Invasive Brown tree snake Kudzu Zebra mussel Introduced to Guam, predated eradicated all native endemic bird Introduced to the South- East USA for their edible leaves pretty flowers. Overgrowing forests, changing native habitats Introduced through boats into Great Lakes, clogging up water intakes, removing food more effective out of water column than natives.

6 Percent of affected Point sources Non-Point sources Air Water Global warming Acid rain Ozone depletion, smog,... Heavy metal Water Body Species Women of childbearing age, young children All Other Individuals (# of meals)* Lake Iamonia Largemouth Bass One per month One per week Water Toxins Nutrients Lake Jackson Lake Miccosukee Black Crappie, Bluegill, Largemouth Bass Bluegill Largemouth Bass One per month Two per week One per month One per week Two per week One per week eutrophic vs oligotrophic PRESS RELEASE, JULY 6, 4 LOUISIANA UNIVERSITIES MARINE CONSORTIUM AVERAGE SIZE "DEAD ZONE" IN ANYTHING BUT AN AVERAGE YEAR Lake Munson Black Crappie, Redear Sunfish One per month One per week The coast-wide extent of the Louisiana "dead zone" mapped this week is slightly larger than average at 15, km (5,8 square miles). The long-term average since mapping began in 1985 is 13, km (5, square miles). The river flow the offshore conditions prior to the mapping cruise were anything but normal were more reminiscent of the Great Mississippi River Flood of The river in 4 peaked in discharge several times in Janua February, March May, followed by a prolonged above average flow that persisted from June into July, as in Moore Lake Largemouth Bass One per month One per week

7 Exploitation Incidental Exploitation Commercial Recreational Bycatch: albatross, whales,... Predator control in parks Recreation Pets s Chytrid, a fungus, is believed to be one of the sources for amphibian decline (Atelopus zeteki) Exploitation s