Instructor and Web Site John Marzluff 123 E Anderson, 616-6883 corvid@u.washington.edu Office Hours (by appointment) E-mail list esrm458a_wi10@u.washington.edu Web Site http://courses.washington.edu/vseminar Helpful Web Sites http://www.wa.gov/wdfw/ (Wa. Dept. of Fish and Wildlife home page) http://www.nceet.snre.umich.edu/EndSpp/factsheet.html (fact sheets on endangered species) http://thomas.loc.gov/home/thomas2.html (links to all legislation) http://www.fws.gov/r9endspp/endspp.html (USFWS Endg. Spp. Home page) http://web.lexis-nexis.com/congcomp (Access to federal register) http://www.fws.gov/laws/digest/digest.html (USFWS law descriptions) http://www.endangeredspecie.com/ (info source for species and pubs) http://www.umich.edu/~esupdate/index.html (Endangered Species Update) Introduction to the Class Goals – Understand the processes of endangerment and extinction – Understand the methods used to recovery endangered species – Understand the legislative environment surrounding endangered species management – Contribute to the recovery of endangered species by working on projects defined by local, regional, and national organizations Introduction to the Class Assumptions – Basic working knowledge of principles of conservation biology • Not going to address reserve design, gap analysis, details of habitat plans, or island biogeography – May be interested in taking ESRM 450, Conservation Biology or Landscape Ecology – Willingness to work outside of class on projects – Willingness to work as a contributing member of a team Introduction to the Class Expectations – Study the reading material • it is EXTENSIVE, but Important – Discuss ideas in class and with classmates outside of class – Prepare a project • suitable for agency/publication • oral and written presentation • can continue on with project as independent study if interested Procedures Text Books – Stanford Environmental Law Society (required) – The Endangered Species Act at Thirty (recommended) Primary literature on the web site Lecture slides on web Guest Lectures Project – Teams,gather information, write report, update us in lab with oral presentations – Interested students can stick with it next quarter for additional credit as needed Rarity and Extinction Why are some species rare? How do we classify rarity? Why are rare species prone to extinction? What is the historical pattern of extinction? Where is endangerment now occurring and what are the causes? Why are Some Species Rare? Body Size Trophic position Geographic distribution – islands – endemics Degree of ecological specialization – niche width Reproductive rate Recentcy of speciation Classification of Rarity (Rabinowitz 1981) Large Range Small Range General Habitat Requirements General Habitat Requirements Specific Habitat Requirements Local Brown Red Populations Rat, Mangrove Somewhere Starling Large Local Peregrine Osprey Populations Falcon everywhere small Specific Habitat Requirements Pygmy Silver Cypress Sword Alala Alpine Lily Giant Panda Why are Rare Species Prone to Extinction? Demographic Stochasticity – By chance alone population fluctuates in growth rate and hence change in size from one year to the next – When population is small, extinction can occur with relatively high probability even if chances of survival and successful reproduction are high Demographic Stochasticity lx = 0.9 (probability of survival) mx = 0.95 (probability of successful reproduction) If only 2 individuals are in area of interest, the probability of extinction approaches 20% – both could die (.10 x .10) = .01 1% – 1 could die (.9 x .1) + (.9 x .1) = .18 18% • thus population would be functionally extinct (no breeding pairs) Why are Rare Species Prone to Extinction? Environmental Stochasticity – random series of environmental changes that affect all members of a population similarly – a couple of bad years in a row can be especially devastating to rare populations • El Nino and Alala – Poor reproduction, even in captivity – Compounding effect of predators (Io) » specializing on crows more? Why are Rare Species Prone to Extinction? Catastrophes – Rare, but huge effects Recent study by Spiller et al. (1998) quantified effects – Hurricane Lili hit Exuma Islands (Bahamas) in 1996 (first since 1932) • high winds and 5m ocean surge – Surveyed lizards and spiders on 19 islands before and after • 11 islands hit full on, 8 were protected by large island Moderate Catastrophe Protected Islands – lizards down 34%, spiders down 79% right after storm • Larger animals can weather moderate disturbances better than small ones – lizards did not increase appreciably during first year, but spiders did • smaller organisms can rebound from catastrophe more quickly because of high reproductive rate – Population size influenced likelihood of extinction in spiders Major Catastrophe Exposed Islands – All lizard and spider populations went extinct – Spiders rebounded within a year, lizards did not recolonize in first year. • First colonist on Krakatoa was also a spider! Why are Rare Species Prone to Extinction? Genetic Problems – Difficulty Finding Mates – Genetic Drift • Inbreeding Depression – Close relatives breed, heterozygosity goes down because they share many alleles, semilethal recessives are expressed more frequently – Aa x Aa gives 25% aa, if a is lethal when homozygous then these offspring will not survive • Random Changes in Phenotype • Decreased Genetic Variance More Genetic Problems Reduction in Effective Population Size – EPS = size of “ideal” population that looses genetic variation at same rate as does real population – Variation is lost at 1/2N% per generation, and replaced at mutation rate per generation--this loss and creation usually balance out – Loss is at > 1/2N% when sex ratios are not balanced, mating is not random, age distribution is not stable, population size is stable, and reproduction is not equal among breeders Effective Population Size Census population was 0.6 Heterozygositiy (all populations) n = 16 flies 0.5 Theory, N = 16 In theory, given ideal 0.4 conditions, we would 0.3 expect decline in 0.2 Theory, heterozygosity to N=9 0.1 follow solid lines. Data 0 Data fits line with 0 10 20 ideal population of n = Generation (t) 9, thus the Ne = 9, not H=2pq(1-1/2N)t, under ideal 16 conditions (theory) Extinction Vortices Summarize the Interaction of Genetic and Demographic Problems (Gilpin & Soule (1986) Environmental changes typically set up positive feedback loops between a population and its environment than accentuate impacts and may lead to extinction – – – – R vortex D vortex F vortex A vortex R Vortex Basically compounding demographic stochasticity – Low N leads to increased variation in r which makes population vulnerable to further disturbances lowering N even more – Low N could lead to skewed sex ratio which makes it difficult to find mates, which lowers reproduction, which lowers N even more, which skews sex ratio further, increasing difficulty, lowering reproduction, lowering N……... D Vortex Lower N affects spatial arrangement of population by increasing fragmentation and isolation of demes Fragments of population are of very small size, so they decline faster, which increases isolation more and speeds decline faster F Vortex Population decline reduces Ne, which increases inbreeding which reduces population growth, lowering N further and increasing inbreeding further A Vortex Population decline reduces Ne and genetic variation which reduces a population’s ability to respond to changes in the environment (loosing race to see Red Queen) – this increases the lack of fit between population and environment, which increases decline further, reducing ability to adapt further….. Combined Vortices All types of vortices feed off one another, greatly increasing probability of extinction in small populations – Population becomes fragmented • each deme is now smaller and susceptible to demographic stochasticity (R vortex) and inbreeding (F vortex) • species cannot adjust to environmental changes (A vortex), so population declines further making it more susceptible to demographic stochasticity (R vortex), which accentuates fragmentation….. What is the historical pattern of extinction? Shallows Mostly Marine Loss of Dinos (Myers 1997) Five major mass extinctions through geologic time – Late Permian--formation of Pangea, loss of shallows, many marine organism extinctions (Schopf 1974) Causes of Historic Extinctions are Varied Meteors Continental Drift Humans – Pattern of extinctions during last 30,000 years (late Pleistocene) closely matches pattern of human colonization Human Occupation of Earth (Diamond 1998--Guns, Germs, and Steel) Recent Extinctions are Most Common in Areas Recently Occupied by Humans Recent Occupancy Many Recent Extinctions Few Recent Extinctions, Long Occupancy byHumans Colors indicate when significant extinction events occurred. Numbers indicate % of fauna that has gone extinct in last 100,000 years (Burney 1993) So, Extinction is Natural, but Current Episode is Unusual Estimated to be 10 - 50 million species on earth – Using 10 million, there are 5 million in tropical forests – 2% of tropical forests are disappearing annually – Translates into 27,000 species / year or 75 per day going extinct in tropical forests alone (Wilson 1992) – This present rate is 10,000x greater than background rate through geologic time (Nott et al. 1995). Global Change and Biodiversity Continental extinction rates have increased from 10-7 to 10-4 species/species/year Nott, et al. 1995. Current Biology 5:14-17 Loss of Species Pales in Comparison to Projected Loss of Populations (Hughes et al 1997) Estimate that there are 220 populations per species (1.1-6.6 billion globally) If population extinction is a linear function of habitat loss, then 1800 populations go extinct each hour in tropical forests alone – 16 million per year!! Estimates Of Extinction Such as This are Based on the Species - Area Curve This loss of area means this loss of species S = cAz Log # of Species Log Area A Global Perspective on Endangerment Baillie’s (1996) analysis of the IUCN Red Data Book Birds appear to be least threatened (at best facing a 10% risk of extinction in the wild in next 100 years) – – – – – 11% of world’s avifauna is threatened 25% of world’s mammals are threatened 20% of world’s reptiles are threatened 25% of world’s amphibians are threatened 34% of world’s fishes are threatened (Pimm et al. 1995; Chapin et al 2000) Vulnerable Orders Loss of all representatives of an Order would be extreme pruning of tree of life Mammal orders at risk – elephant, manatees, marsupial moles,opossum-like Microbiotheria --all species threatened – horses, tapirs, rhinos; elephant shrews; monotremes; hyraxes; flying lemurs Bird orders at risk – cranes, galliformes, parrots, doves, kingfishers & beeeaters, procellariiformes, grebes, kiwis, cassowaries More Vulnerable Orders Reptiles – tuatara, crocs, turtles are only groups well surveyed and all have high level of threat (~40%) Fishes – sturgeon & paddle-fish, coelacanth, minnows, perch Inverts – poor info, but mollusks top the list Severity of Extinction 10% of all birds are threatened with extinction – Not Random among families • Parrots, rails, cranes, pigeons, albatrosses, megapodes – Low reproductive rates (Bennett and Owens 1997 Proc. Royal Soc. Lond 264:401-408) – Should prioritize conservation efforts for these species » (Hughes 1999. Bird Conservation International 9:147-154) – Concentrated among island species • First colonists to pacific islands exterminated 50% of the native birds • Even worse on Hawaii—90-110 of 125-145 are extinct (Pimm et al. 1994. Phil. Trans. R. Soc. Lond. 344:27-33) Geography of Vulnerability Mammals – Indonesia (128), China and India (75 each), Brazil (71),………USA (35) – Madagascar (44%), Philippines (32%) Birds – Indonesia (104), Brazil (103), China (90) – Philippines (15%), New Zealand (15%) Reptiles, Amphibians, Fishes, Inverts – Poorly assessed, but USA and Australia top the lists Biodiversity is not evenly distributed across Earth 5% of Earth holds 95% of most vulnerable bird species (Bibby 1994, Proc. Royal Soc. Lond.344:35-40. US Patterns of Rarity, Endemism, Extinction, and Listings Dobson et al. 1997 Nature Serve 2000, 2002 – http://www.natureserve.org/index.jsp “At Risk” Species at Risk Endemic Species Plant diversity, endemism, and rarity 5-4a,b,c Source: Precious Heritage (2000) © TNC, NatureServe Vertebrate diversity, endemism, and rarity 5-6a,b,c Source: Precious Heritage (2000) © TNC, NatureServe Distribution of Federally Listed Species 6-1 Source: Precious Heritage (2000) © TNC, NatureServe County Distribution of Federally Listed Species 6-2 Source: Precious Heritage (2000) © TNC, NatureServe Distribution of Imperiled Species by Ecoregion Number of Species Number of Endemic Imperiled Species 1-20 1-10 21-50 11-50 51-150 51-150 > 150 > 100 6-5 Source: Precious Heritage (2000) © TNC, NatureServe What Reasons are Listed For Endangerment in US? (Czech and Krausman 1997) Cause # Endangered Interactions with nonnatives Urbanization Agriculture Outdoor recreation, tourism Ranching Water diversions Modified fire regimes, silviculture Pollution of water, air, soil Energy exploration 305 275 224 186 182 161 144 Industry and military 131 144 140 What Reasons are Listed For Endangerment in US? (Czech and Krausman 1997) Cause Harvest, intentional and incidental Logging Roading Genetic problems (inbreeding, etc) Wetland destruction Plant succession Disease Vandalism (destroy, but no harvest) # Endangered 120 109 94 92 77 77 19 12 How Many Extinctions Have Been Documented in last 400 years? Total of 611 totally gone, 30 more extinct in the wild() – – – – – – – – – Mammals 86 (3); 1.8%, most in Australia & West Indies Birds 104(4); 1.0%, most in Mauritius, US, N Zealand Reptiles 20 (1) Amphibians 5 (0) Fishes 81 (11) Molluscs 230 (9); mostly gastropods on islands Crustaceans 9 (1) Insects 72 (1) Other inverts 4 (0) Extinctions Evil Quartet (Diamond 1989) Overkill – whales Habitat Destruction and Fragmentation Impact of Introduced Species Chains of Extinction – plants in Hawaii after loss of pollinators Revisiting Threats Habitat degradation/loss Alien species Pollution Overexploitation Disease (Wilcove et al. 1998 BioScience 48:607-615) Naiveity?? (Berger et al. 2001. Science 291:1036-1039) Climate Change Has Extinction Slowed Diversification? Shallows Mostly Marine Loss of Dinos (Myers 1997) Overall increase of familial diversity despite extinctions Modeling study suggests that tree of life can be vigorously pruned and still maintain diversity Nee and May (1997) – What fraction of evolutionary history in a taxon is left when some proportion of species are lost? – Losing 80% of the species still preserved 50% of evolutionary history (measured as branches in phylogenetic tree) – Doesn’t matter if we chose species at random or optimally based on genetic history But, Importance of Species Loss To Rest of Ecosystem Depends on its Role Many species perform critical ecosystem services (keystones in that regard) – soil generation, pest control, regulation of weather and climate, nutrient cycling, seed dispersal, etc, etc (Daily et al. 1997). So extinctions may have snowball effects Remember that the reason we can document extinctions from the past is in large part because of the loss of dinosaurs in Late Cretaceous! Does it Matter? Hell Yes – Much is unknown, so save the parts • (Aldo Leopold once said the first sign of an intelligent tinkerer is to save all the parts) – Biodiversity is connected to ecosystem function • Loreau 2000. Oikos 91:3-17 – How many rivets can we pop? • Ehrlich and Ehrlich 1983. Extinction: the causes and consequences of the disappearance of species. New York: Ballatine Books So, What Do We Do? Use Scientific Method to Identify Threat Determine Spatial Extent of Protection--Gap Analysis ? Set up Reserves REMOVE THREAT Release Probe to Test if Threat is Removed Captive Breeding Restock Manage in situ Monitor Recovery Recommendations to Save Birds in the Americas Secure sites Locate new sites Estimate population size in sites Study ecology Manage sites Control taking Educate people Captive management Taxonomic study Other Bibby 1994 Proc Roy Soc Lond 344:35-40 241 214 197 164 91 49 23 23 8 14 Example--Lord Howe Island Woodhen Down to 20 individuals, confined to two mountain tops Did experiments to determine impacts of – food availability – rat predation – pig predation Remove Pigs Captive Breed, reintroduce, local stock Population up to 160 and stable Now should do reserve planning to manage entire island References Rabinowitz, D. 1981. Seven forms of rarity. In The biological aspects of rare plant conservation. H. Synge (Ed.), Wiley & Sons, Chichester. UK. Gilpin, ME and ME Soule. 1986. Minimum viable populations: processes of species extinction. Pp 19-34. In. ME Soule (ed.) Conservation Biology. Sinauer, Sunderland, MA. Pister, EP. 1993. Species in a bucket. Natural History January:14-19. Diamond, J. M. 1989. The present, past and future of human-caused extinction. Philos. Trans. R. Soc. London B 325:469-478 References Myers, N. 1997. Mass extinction and evolution. Science 278:597-598. Schopf, TJM 1974. Permo-Triassic extinctions: relation to sea-floor spreading. J. Geology 82:129-143. Daily, GC. Et al. 1997. Ecosystem services: benefits supplied to human societies by natural ecosystems. Issues in Ecology #2 Wilson, EO. 1992. The diversity of life. Belknap Press, Cambridge Ma. Grant, PR. 1995. Commemorating extinctions. Am. Scientist 83:420-422. References Meffe, GK and CR Carroll. 1994. Principles of conservation biology. Sinauer, Sunderland, MA Hughes, JB, GC Daily, and PR Ehrlich. 1997. Population diversity: its extent and extinction. Science 278:689-691. Dobson, AP. Et al. 1997. Geographic distribution of endangered species in the United States. Science 275:550553. Czech, B. and Krausman, PR. 1997. Distribution and causation of species endangerment in the United States. Science 277:1116. References Baillie, J. and B. Groombridge. (eds). 1996 IUCN Red list of threatened animals. IUCN, Gland, Switzerland and Cambridge, UK. 448 p. Spiller, D. A., J. B. Losos, and T. W. Schoener. 1998. Impact of a catastrophic hurricane on island populations. Science 281:695-697. Nott, et al. 1995. Current Biology 5:14-17 Pimm, SL, Russell, GJ, Gittleman, JL and TM Brooks. 1995. The future of biodiversity. Science 269:347-350. Chapin, FS III, et al. 2000. Consequences of changing biodiversity. Nature. 305:234-242.