The Body Size of Headstarted and Wild Juvenile European Pond Turtles (Emys orbicularis)

Sławomir Mitrus, Bartłomiej Najbar, Adam Kotowicz, Anna Najbar


Headstarting is a popular conservation technique in which animals are raised under artificial conditions, and then released into natural habitat. The objective of this procedure is to grow animals to a size at which they are less vulnerable to predators. However, there is still little empirical evidence for the long-term effectiveness of the technique. Therefore, we compared body size of juvenile «wild» (= not taken to artificial rearing) and headstarted European pond turtles (Emys orbicularis), from two populations (in central and western Poland). Immediately after hatching there were no differences in size of the turtles, but after seven-ten years headstarted turtles were smaller. This sound alarming, but our samples are small, and thus it is impossible to far-reaching conclusion; good comparative data on «wild» and headstarted animals are urgently needed.


captive rearing; conservation; freshwater turtles; growth rates; headstarting

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