Literaturdatenbank
Literaturdatenbank |
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Caldwell, I. R. (2003). Terrestrial movement of eastern painted turtles (chrysemys picta picta schneider) in unfamiliar habitat. Unpublished thesis , Nova Scotia Agricultural College, Truro, Nova Scotia.
Added by: Admin (29 Jan 2012 12:38:37 UTC) |
| Resource type: Thesis/Dissertation BibTeX citation key: Caldwell2003 View all bibliographic details  |
Categories: General Keywords: Schildkröten = turtles + tortoises, Verhalten = ethology Creators: Caldwell Publisher: Nova Scotia Agricultural College (Truro, Nova Scotia) |
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| Abstract |
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All turtles must journey on land for parts of their life cycle. Adult painted turtles spend the majority of their lives in aquatic environments but must leave to excavate terrestrial nests and to migrate in habitats where necessary. The terrestrial environment is hostile with increased risk of mortality from predation, dessication, and starvation. In order to make overland trips in familiar habitat as short as possible, painted turtles have evolved mechanisms allowing them to detect and navigate towards known bodies of water. If a turtle's home lake is destroyed, however, they must travel over land to a new lake or die. This study was designed to test whether painted turtles are also able to detect and navigate towards an unfamiliar body of water. Sixty eastern painted turtles were released in unfamiliar territory at five distances from an unfamiliar lake for this purpose. Thread packets attached to each turtle's carapace allowed for collection of trail coordinates by following the turtle's path with a GPS unit. Orientation and tortuosity of the trails at each release distance were then determined from those coordinates. V-tests revealed that turtles did not orient towards water even when released as close as 100 metres from the lake but fractal analysis showed that all of the turtle trails were relatively straight, regardless of release distance. Eastern painted turtles may use a compass mechanism to navigate in both familiar and unfamiliar territory allowing them to maintain their direction in both situations. In unfamiliar territory it is an effective search strategy but the initial choice of direction is random so it is not as effective as when homing.
Added by: Admin |