The reproductive ecology of exotic Trachemys scripta elegans in an invaded area of southern Europe



  • 1.The main reproductive parameters of exotic Trachemys scripta elegans in established populations from two ponds in southern Spain are described.
  • 2.Females were found to reproduce at 5 years of age, although sexually mature individuals of 4 and 3 years of age were also detected. Annual reproductive frequency was estimated to be 80–86% of reproductive females. Mean clutch size was 11.5 eggs and was not correlated with maternal body size.
  • 3.The number of follicles of different size in ovaries suggested that four or more clutches could be laid per season. Eggs were laid from April to June (inclusive) mainly during morning hours, when females were easily detected during nesting trips. 79.5% of eggs were fertile.
  • 4Reproductive parameters of this species in southern Spain were of similar or even higher values than in native areas, thus placing them among chelonian species of earlier maturity.
  • 5.Although chelonians might never be considered explosive breeders, the number of T. s. elegans individuals could surpass that of native aquatic chelonians in southern Spain, where T. s. elegans reach maturity earlier, are more fecund and their eggs are more fertile.

Copyright © 2008 John Wiley & Sons, Ltd.