Angulate and leopard tortoises in the Thicket Biome, Eastern Cape, South Africa: populations and biomass estimates

The population parameters (morphometrics, population size and biomass) were determined for leopard and angulate tortoises in the Thicket Biome, Eastern Cape, South Africa. Leopard tortoises had a mean total length of 306.47mm (SD = 94.65mm, range 59–496mm,n = 89). Males were smaller (mean total length 277.31mm, SD = 71.85mm, range 73–377mm,n = 36) than females (mean total length = 332.33mm, SD = 97.64mm, range 59–496mm, n = 53). Angulate tortoises had a mean total length of 155.17mm (SD = 33.89mm, range 59–194mm, n = 18). Males were larger (mean total length = 186mm, SD = 8.40mm, range 174–194mm, n = 5) than females (mean total length = 143.31mm, SD = 32.48mm, range 59–178mm, n = 13). The estimated population density for leopard tortoises was 0.85 tortoises ha−1 with an estimated biomass of 6.02kg −1. Angulate tortoise population density was estimated at 0.12 tortoises ha−1 with a mean biomass of 0.06kg ha−1. The possible consequences of this high density and biomass are discussed. Resume On a determine les parametres (morphometrie, taille des populations et biomasse) des populations de tortues leopards et de tortues angulees dans le Thicket Biome, Province du Cap oriental, en Afrique du Sud. Les tortues leopards avaient une longueur totale moyenne de 306,47 mm. (SD = 94,65 mm., ecart 59–496mm., n = 89). Les mâles etaient plus petits (longueur totale moyenne = 277,31 mm., SD = 71,85 mm., ecart 73–377 mm., n = 36) que les femelles (longueur totale moyenne = 332,33 mm., SD = 97,64 mm., ecart 59–496 mm., n = 53). Les tortues angulees avaient une longueur totale moyenne de 155,17 mm. (SD = 33,89 mm., ecart 59-194 mm., n = 18). Les mâles etaient plus grands (longueur totale moyenne = 186 mm., SD = 8,40 mm., ecart 174-194 mm., n = 5) que les femelles (longueur totale moyenne = 143,31 mm., SD = 32,48 mm., ecart 59-178mm., n = 13). L'estimation de la densite de population des tortues leopards etait de 0,85 tortue/ha., avec une biomasse estimeea 6,02 kg/ha. On a estime la densite de population des tortues angulees a 0,12 tortue/ha., avec une biomasse moyenne de 0,06kg/ha. On discute les consequences possibles de ces hautes densites et biomasses.