Literaturdatenbank
Literaturdatenbank |
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Hewitt, C. L., Lewis, T. L., & Hawkins, N. R. , A 26-year study of the population dynamics of spotted turtles (clemmys guttata) in southwestern ohio. Paper presented at Turtle Survival Alliance 2007 Annual Meeting.
Added by: Admin (13 Dec 2008 22:23:42 UTC) |
| Resource type: Proceedings Article BibTeX citation key: Hewitt2007 View all bibliographic details  |
Categories: General Keywords: Clemmys, Clemmys guttata, Emydidae, Habitat = habitat, Nordamerika = North America, Schildkröten = turtles + tortoises Creators: Hawkins, Hewitt, Lewis Collection: Turtle Survival Alliance 2007 Annual Meeting |
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| Abstract |
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Spotted turtle (Clemmys guttata) populations have been decreasing across their range due to a number of factors including habitat isolation and loss, over collection for the pet trade, and increased predation thus resulting in the species being currently listed as threatened in 4 states including Ohio. Spotted turtles were collected in Clark County, Ohio from 1981 to 2006 in order to determine sex ratios and population levels. Specimens were collected by muddling, trapping, and systematic searches. A total of 177 different specimens were captured 475 times. The average yearly ratio of females to males was 1.34:1, with females composing 60.8% and males 39.2% of the adult turtle population during the study period. Both Lincoln-Peterson and minimum population estimates were used to analyze trends in population levels. The minimum population peaked in 1992 at 75 turtles; the greatest Lincoln-Peterson estimate was 129 turtles in 1997. Since the mid-1990’s, the population has steadily declined. A population of fifty individuals is necessary for short term viability, thus rendering the studied population in danger of extirpation.
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