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Unformatted text preview: Metapopulations Metapopulations
Levins Model Mainland-Island Model Levins Model If e >c, metapopulation extinction High c p P p Time 10 July Pe rm
v v an en t Low c 1 Metapopulations Mainland-Island Model High m p P p Study of Pikas on Abandoned Mine Sites by Andrew Smith by
Pikas have inhabited the sites since the end of the 19th century Censused 74 sites from 1972-1991 always occupied always empty became extinct colonized 10 July v v Low m Time 2 Metapopulations Study of the Bay Checkerspot Butterfly by Susan Harrision
A severe drought 1975-1977 caused extinction of all populations except MH In 1987, the area contained 27 suitable sites for populations: 9 of 27 sites were occupied; all 9 were <4.4 km from MH, suggesting that a Mainland-Island Metapopulation existed Population sizes on 7 sites (estimated by mark-recapture method) ranged from 10 to 344. Assuming no extinctions, 17 of the 27 suitable sites will be occupied after 50 years (the time to the next severe drought) Metapopulations of Two Spider Species on Bahamian Islands
by Thomas Schoener and David Spiller
Counted the number of web spiders on 48 “suitable” small islands 1981-1993. Conclusions
Metepeira exhibits relatively stable population dynamics with low extinction and colonization rates Argiope exhibits relatively unstable population dynamics with high extinction and colonization rates Metepeira populations are more likely to persist during “normal” years, but following a major catastrophe, Argiope will recover faster 10 July 3 ...
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This note was uploaded on 01/06/2010 for the course EVE 101 taught by Professor Strong,d during the Spring '08 term at UC Davis.
- Spring '08