Literaturdatenbank
Literaturdatenbank |
|
 |
|
Lindeman, P. V. , Aspects of molluscivory in the alabama map turtle (graptemys pulchra) - abstract. Unpublished paper presented at Program and Abstracts of the Tenth Annual Symposium on the Conservation and Biology of Tortoises and Freshwater Turtles.
Added by: Admin (06 Jan 2014 18:22:56 UTC) |
| Resource type: Conference Paper BibTeX citation key: anon2012.14554 View all bibliographic details  |
Categories: General Keywords: Emydidae, Ernährung - nutrition, Graptemys pulchra, Habitat - habitat, Nordamerika - North America, Schildkröten - turtles + tortoises Creators: Lindeman Collection: Program and Abstracts of the Tenth Annual Symposium on the Conservation and Biology of Tortoises and Freshwater Turtles |
Views: 5/595
Views index: 15% Popularity index: 3.75% |
| Abstract |
|
Map Turtle and Sawback females segregate into micro-, meso-, and megacephalic groups with relatively predictable differences in the importance of mollusks in the diet. Mesocephalic females consume large numbers of mollusks, but typically also feed to varying degrees on other softer-bodied prey. Females of the megacephalic clade appear to feed almost exclusively on mollusks, although detailed dietary studies have been conducted for only two of these five species. I studied the diet of the Alabama Map Turtle (Graptemys pulchra) via collection of feces from animals captured in the Alabama River in Autauga and Lowndes counties, Alabama. Data on percent frequency of occurrence and mean percent of sample volume were used to calculate an Index of Relative Importance (IRI) for each prey taxon for hatchlings, adult males, and females (including mature and immature females larger than minimum male size); IRI values sum to 100 within each class of turtles. Hatchlings were strict insectivores. Adult males had surprisingly high IRI values for native bivalves (26) and the invasive Asian clam, Corbicula fluminea (55), given their small body size. Juvenile and adult females fed almost exclusively on native bivalves (39) and Asian clams (59) and also took occasional snails (1). Surprisingly, many of the native bivalves passed by females were uncrushed, with both valves intact and connected at the hinge; Corbicula shells from females were nearly always disconnected at the hinge and were significantly more likely to consist of fragmented valves. These findings represent the highest importance of native bivalves in any recent report of Graptemys diets (i.e., post-invasion by Corbicula) and raise the possibility that some Graptemys females may be useful sources of information in efforts to survey native bivalve distribution and abundance.
Added by: Admin |