Literaturdatenbank
Literaturdatenbank |
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Schneeweiß, N. (2004). Age structure of relict populations of the european pond turtle (emys orbicularis) at the northwestern boundary of its range. Biologia (Bratislava), 59(Suppl. 14), 123–129.
Added by: Admin (06 Jan 2014 18:23:09 UTC) |
| Resource type: Journal Article BibTeX citation key: anon2004i View all bibliographic details  |
Categories: General Keywords: Emydidae, Emys orbicularis, Europa - Europe, Habitat - habitat, Schildkröten - turtles + tortoises Creators: Schneeweiß Collection: Biologia (Bratislava) |
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| Abstract |
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The age structure of small relict populations of Emys orbicularis was investigated over eight years (1994–2001) in northeastern Germany (Brandenburg). A comparison of cross-sections of the humeri and shell growth rings revealed largely identical growth ring numbers, corresponding to annual growth cycles. Shell growth rings are a powerful tool for age determination in young turtles up to an age of approximately 18 years. In older individuals, the shell shows a progressive loss of growth rings. Based on empirical data, age classes were defined for a rough age determination of aged turtles. 49 adults were assigned to these age classes, resulting in a well-balanced age distribution. The rate of old and very old individuals (> 30 years) is among females considerably higher than among males.
Added by: Admin |