Ciência e Tecnologia Veterinária

Size and Sex Constraints in Self-Uprigthing in Western Hermannâ??s Tortoise Testudo hermanni (Gmelin 1789)

Abstract

Parés Casanova PM* and Coronado C

Self-righting occurs when the animal rights itself after been overturned on the back, a phenomenon far more pronounced in males than females, as belligerent males often try to flip opponents over during fights for territorial contests. It is said that bigger tortoises struggle to right themselves more than smaller tortoises. Here we studied experimentally this self-righting behaviour in western Hermann's tortoise (Th hermanni) in a sample of 30 adult specimens (17 males and 13 females). Body length (lineal distance of plastron) and body weight were obtained at the same time of the experiment. There appeared statistical differences in up-righting time differences between sexes, being those of male are shorter (0.94’ ± 0.88 and 1.45’ ± 1.12 for males and females respectively). This time was also correlated with body length but not with body weight. The body length probably is limited to a certain size in order to avoid excessive up-righting periods.