Foraging Behavior and Diet Preferences of a Released Population of Giant Tortoises in the Seychelles

Abstract

Abstract This study evaluates the potential impacts of the release of the giant tortoise, Dipsochelys arnoldi, to vacant habitat within the species' presumed historic range. Five individuals (3 males and 2 females) were released in December 2006 in the isolated Grande Barbe area of Silhouette Island, Seychelles. A comprehensive vegetation survey of all plant species within feeding height of the tortoises in Grande Barbe was conducted. These data, combined with daily feeding observations, were used to calculate feeding rates and diet preferences. Tortoises were observed to have a mean diurnal active time of 257 minutes per day exhibiting a mean feeding rate of 3.86 g of plant material consumed per minute of active time. Individuals were recorded feeding on 18 of 26 recorded plant species, 9 of which were selectively foraged. Species composition of plant species ingested differed between sexes. Males selectively foraged on 6 plant species and females selectively foraged on 7 species. Only 2 plant species we...