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Society for Conservation Biology

Society for Conservation Biology. Auburn University Chapter. Guest Speaker: Dr. Sharon Hermann “Longleaf Pine Ecosystem Restoration” Plus: Night Swamp Walk (Shawn Jacobsen and Dr. Folkerts). WHERE? 112 Rouse Life Sciences. WHEN? TUESDAY Sept. 17 6:00-7:00 PM Swamp walk to 11 PM.

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Society for Conservation Biology

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  1. Society for Conservation Biology Auburn University Chapter • Guest Speaker: Dr. Sharon Hermann • “Longleaf Pine Ecosystem Restoration” • Plus: Night Swamp Walk (Shawn Jacobsen and Dr. Folkerts) WHERE? 112 Rouse Life Sciences WHEN? TUESDAY Sept. 17 6:00-7:00 PM Swamp walk to 11 PM Check us out at www.auburn.edu/scb • Also: Info on Sept. 21 (Saturday morning) longleaf pine restoration tour on campus

  2. Extinction (Ch. 7) website

  3. Definitions/Concepts • “The living dead” • Long-lived organisms: in habitat fragments too small • Ex: St. Helena ebony • 2 plants left on cliff

  4. Definitions/Concepts • “Extinction Debt”: Eventual loss species from remaining habitat fragments Brazil rainforest 2005 Red is forest

  5. Unknown extinctions • 1) Some species thought extant (still living) are extinct (we don’t know it yet) • 2) Undescribed species probably go extinct before collected Taxonomy:

  6. Is extinction forever? Maybe... • Rediscoveries (Lazarus species) • Ex: Gomeran giant lizard. photo

  7. Is extinction forever? Maybe... • 1.5 ft long (La Gomera Island) • Feral cats killed by 1490s? • Few on steep cliffs 1999. A modern cat on the hunt….

  8. Is extinction forever? Maybe... • Ivorybill woodpecker! • Feb 2004: Arkansas The search team

  9. Is extinction forever? Maybe... • Alabama freshwater snails: 44 species Mobile River basin extinct • 2004: 3 species rediscovered!! Press Conference…..

  10. Earth’s Extinctions • 6 major extinctions

  11. #6: Pleistocene Extinction • Started 30,000 yr ago • Toward end last ice age

  12. #6: Pleistocene Extinction • Arrival humans followed by extinctions of megafauna (animals >100 lb).

  13. Hawaiian bird extinctions • 80% Hawaii’s birds extinct or endangered Micro- Poly-nesia Hotspot!

  14. Hawaiian bird extinctions • 55 species (extinct Polynesians) • Some (ex, “mamo bird”) hunted (feathers) • 1 cape: 70,000 mamo birds! Feather lei (left), helmet (above), and feather capes (right) Mamo bird

  15. NZ Hotspot! New Zealand’s Moas • Large flightless birds: 11 species • Extinct by Maori. Giant moa replica, and human for scale Giant moa leg bones

  16. Humans driving species extinct prior to European arrival Lecture 1 • Europeans continued… • Great Auk

  17. Europeans • Worse than many other cultures • 1) Land clearing greater • 2) Introduced species: rats, dogs, cats, pigs, goats, sheep, horses, cattle, etc. Bad European…. Weaponized goat…

  18. Extinction rates (1600-now) • Best known: mammals (1.6%), birds (1.3%) • Birds: Decline (Fig. 7.4) due to delay in declaring species extinct Fig. 7.4 Bird extinctions

  19. Extinction rates (1600-now) • New candidates building up…..threatened % large

  20. Hundred Heartbeat Club • E. O. Wilson: Species <100 individuals (globally!) • Who am I? Hundred Heartbeat Club is on Facebook!

  21. Rates of extinction • How much due to humans?? • Calculate: • 1) Background rate (how?) • 2) Current rate • Fossils: How define • Species? • Phylogenetic (DNA) • Biological • Morphological

  22. Rates of extinction • Study 1: current 100-1000x greater • Study 2: current 36-78x more than background • Bottom line: Current rate >35x background

  23. New Earth Epoch: Anthropocene • Global processes dominated by humans! • 1) Extinctions

  24. New Earth Epoch: Anthropocene • Global processes dominated by humans! • 1) Extinctions • 2) Ecosystem cycles (H2O, C, N) • 3) Sedimentation (geol. record)

  25. U.S. State ranks for extinction • April 2002 report (pdf posted on class webpage) • Presumed extinct + possibly extinct • #1: Hawaii (217)

  26. U.S. State ranks for extinction • April 2002 report (pdf posted on class webpage) • Presumed extinct + possibly extinct • #1: Hawaii (217) • #2: Alabama (90) • Why?

  27. U.S. State ranks for extinction • #2: Alabama (90) • Mostly freshwater organisms • 17 mussels, 25 snails…… • Dams Lake Jordan Dam, Alabama

  28. U.S. State ranks for extinction • April 2002 report (pdf posted on class webpage) • Presumed extinct + possibly extinct • #1: Hawaii (217) • #2: Alabama (90) • #3: California (53) • #4: Texas (27) • #5: Georgia (26). Mikheil Saakashvili: President of Georgia

  29. Extinctions and Islands • 50% terrestrial species extinctions: on islands • Why?? Fig. 7.4 Bird extinctions

  30. Extinctions and Islands • Why?? • 1) Endemism high: adaptive radiation generates new species • 2) Small range/habitat/pop’n. size • 3) Vulnerable (invasive species, diseases, small range….) Case study: Stephen’s Island wren Lecture 1…….

  31. Island Extinctions: The Case of the Stephens Island Wren • New Zealand wrens: Xenicidae (6 species) • 3 extinct on main islands (rats) J. Cagney Stephens Island Wren “You dirty rat……”

  32. Stephens Island Wren • 1 population on Stephens Island (1 sq. mile area) • 1890s: Lighthouse built • Keeper’s cat (“Tibbles”) End…

  33. Island Extinctions: The Case of the Stephens Island Wren • 1 cat* discovered & drove extinct the last of a species! Bird feeder, or cat feeder?? *Attorney’s Note: More than one cat may have been involved career

  34. Domestic Cat Predation • Estimates: • US: 40 million cats allowed outside • 60-100 million homeless cats • 4-5 million birds killed/day • 1 billion small mammals killed/year!

  35. Extinctions and Island Biogeography • BIOL 3060 review! • MacArthur & Wilson (E.O.) • Relates species richness to island size & isolation

  36. Island Biogeography • Model: immigration and extinction rates affected by island size and distance to mainland

  37. Island Biogeography • Model: immigration and extinction rates affected by island size and distance to mainland

  38. Island Biogeography • Area increases: species richness increases Hotspot! Reptiles & Amphibians Caribbean Islands Fig. 7.8 Log/log scale Slope <1

  39. Log/log scale Slope <1 Island Biogeography • Formula: S=CAZ • S=number species A=area • C is constant (high for species-rich groups, like insects) • Z is constant (high for groups with restricted geographic ranges, like reptiles) • Ex, 10-fold increase area gives 2-fold increase species richness.

  40. Habitat islands and extinction • CONCEPT: Calculate species loss as habitat lost Fig. 7.10 in text NOTE SHAPE OF CURVE!! Data?

  41. Habitat islands and extinction • Ex, birds on Singapore • Last 180 yr, 95% forest gone • Model for birds: predicts 30% species loss • 32% extinct since 1923 Rainforest loss….

  42. Habitat islands and extinction • Rainforest use: • If 1% destroyed/yr • 10,000-15,000 species extinct/yr (assuming 5 million species total) • 34 species/day

  43. Habitat islands and extinction • Controversial--assumptions/generalizations: • 1) Curves vary (by taxon) • 2) Cleared habitat assumed unsuitable • 3) Pattern fragmentation matters

  44. Aquatic Extinctions(“Death Aquatic”?)

  45. Aquatic Extinctions (Marine) • Good news: 21 species extinct past 300 yrs (16 since 1972!) • Bad news: underestimate (lack knowledge) Caribbean monk seal

  46. Aquatic Extinctions (Fresh) • Freshwater extinctions high: mainlands mostly (species richness greatest) • US: TN, AL, GA, FL (SE) most freshwater species at risk. Fig. 7.7 Fish & mussels

  47. Local extinctions • Less attention than global: but more occur!! % populations left % habitat preserved Shape curve?

  48. Local extinctions • Conservation problem: • 1) Decrease community diversity

  49. Local extinctions • Conservation problem: • 2) Decrease genetic diversity of species Fig. 7.12

  50. Local extinctions • Conservation problem: • 3) Decrease evolutionary potential (adaptation/speciation) Fig. 2.4

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