Growth and carapacial colour variation of the leopard tortoise, Geochelone pardalis babcocki , in northern Tanzania

Observations were made of growth rate and variation in colour pattern of the leopard tortoise ( Geochelone pardalis babcocki ) in northern Tanzania between October 1993 and June 1996. Growth rate differed significantly between tortoises, with immature animals (6.9 ± 1.4 mm month −1 ) and females (5.7 ± 1.3 mm month −1 ) exhibiting higher rates of growth than adult animals (2.9 ± 0.8 mm month −1 ) and males (3.2 ± 1.1 mm month −1 ), respectively. The faster growth rate in immature animals suggested that growth rate declined with age. The difference in growth rates between the sexes was ascribed to sexual dimorphism, adult females being larger and therefore growing faster than males. The carapacial colour pattern observed in the northern Tanzanian tortoises was generally similar to that described elsewhere in the species' range. The colour pattern varied between Arusha and Serengeti District tortoises. Animals at the Arusha sites tended to be sparsely coloured (55.6%) compared to the Serengeti tortoises, which had a buff colouration with radiating spots (89.3%).; The sparse colouration provides effective camouflage in the drier Arusha habitats, as does the buff colouration with black spots in the wetter, darker habitats in the Serengeti.