Chelonoidis chilensis is an endemic Argentine tortoise. It is considered by the IUCN (International Union for the Conservation of Nature) to be a vulnerable species, being the most traded native reptile in the illegal pet market. At present, little is known about the reproductive biology of this chelonian, therefore the aim of this paper is to contribute to the knowledge on reproduction and growth in captivity of C. chilensis. We used adult tortoise of both sexes, separated into two reproductive enclosures, and their growth was recorded monthly over a period of 12 months. The collected eggs were artificially incubated under controlled conditions of temperature and humidity. The period of copulation occurred between November and January and the nesting season was observed between January and April. The incubation period was 9 months with a hatching success of 8.7%; and the percentage of adult mortality was 23.5%. No significant differences in growth between sexes were found, this being a possible strategy of the species to reduce energy costs associated with metabolic maintenance after the reproductive stage.

Fil: Parachu Marco, Maria Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina

Fil: Romito, María Laurq. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias; Argentina

Fil: Imhof, Alba. Universidad Nacional del Litoral. Facultad de Humanidades y Ciencias; Argentina