Literaturdatenbank
Literaturdatenbank |
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Lescher, T. C. (2010). Relative abundance, population structure, and habitat utilization of the alligator snapping turtle (macrochelys temminckii) and eastern snapping turtle (chelydra serpentina) in southeastern missouri. Unpublished thesis , University of Missouri - St. Louis, St. Louis, Mo.
Added by: Sarina Wunderlich (06 Jul 2014 16:11:47 UTC) |
| Resource type: Thesis/Dissertation BibTeX citation key: anon2010w View all bibliographic details  |
Categories: General Keywords: Chelidae, Elseya branderhorsti, Elseya dentata, Elseya irwini, Elseya lavarackorum, Habitat - habitat, Nordamerika - North America, Schildkröten - turtles + tortoises Creators: Lescher Publisher: University of Missouri - St. Louis (St. Louis, Mo) |
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| Abstract |
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Alligator Snapping Turtles have not been surveyed extensively in Missouri since 1993-94. Six sites that were sampled in the early nineties were re-sampled in 2009 at the same locations where previous researchers trapped. Significantly fewer significantly fewer Alligator Snapping Turtles were captured per trapnight at all six sites. The population structure of the Alligator Snapping Turtles had a significantly different distribution in 2009 compared to 1993-94. The population structure had shifted toward smaller individuals, and fewer adult males and adult females were captured in 2009 compared to 1993-94. The 1993-94 structure was normally distributed while the 2009 structure exhibited a negative skew. Populations sampled in 2009 have an extremely female-biased sex ratio and fewer large adults, which may impact the population negatively in the future. Future sampling of Alligator Snapping Turtles at these six sites is recommended to continue monitoring their long-term trends in relative abundance and population structure. Alligator Snapping Turtles (Macrochelys temminckii) and Eastern Snapping Turtles (Chelydra serpentina) were captured during the summers of 2009 and 2010. Habitat characteristics were collected at each trap that captured these species. Subsequent analysis of data revealed that Alligator Snapping Turtle presence at trap sites was characterized by increased physical structure in the stream, water depth, relatively high levels of detritus, and warmer temperatures when compared to Eastern Snapping Turtles; the amount of aquatic vegetation and bottom surface (i.e., mud or non-mud substrate) were important in characterizing Eastern Snapping Turtle presence in traps. Eastern Snapping Turtles and Alligator Snapping Turtles did not use the same areas spatially, and were only trapped at the same location once in 557 trapnights. Future conservation plans for the Alligator Snapping Turtle and Eastern Snapping Turtle should consider the microhabitat characteristics of sites utilized by these turtles, along with the possibility of interspecific interactions within Chelydridae.
Added by: Sarina Wunderlich |