Oviducal Period and Egg Shell Calcification in the South African Tortoise Chersina angulata

Abstract. Chersina angulata egg retention times differ among sequentially ovulated eggs from February to November, being shorter in eggs ovulated in October and November than in eggs ovulated in February, April, May, and July. More time is required to achieve eggshell calcification from July to October than from March to June. In most instances (71%) females lay their eggs when the eggshell still appears relatively thin on the radiographs, with only few eggs becoming more prominently calcified prior to oviposition.