REPRODUCTIVE ALLOMETRY OF Podocnemis expansa (TESTUDINES, PODOCNEMIDIDAE) IN SOUTHERN BRAZILIAN AMAZON

PORTELINHA, T.C.; MALVASIO, A.; PIÑA, C.I.; VERDADE, L.M.; BERTOLUCI, J.

Buenos Aires

Congreso; XI Congreso Argentino de Herpetologia; 2010

Asociacion Herpetologica Argentina

Podocnemis expansa is the largest freshwater turtle in South America, showing a complex reproductive behavior. Females lay eggs in sandy banks formed during the dry season. Nesting habitat can influence hatching success, sex determination and survival of eggs and hatchlings. Some studies have shown that female body size is crucial to determine clutch parameters such as eggs’ and hatchlings’ size and number as well as nest shape in some turtle species. In this study we investigated allometric relationships between females’ body size with clutch characteristics and nest shape in sandy beaches along Javaés River, in Southern Brazilian Amazon between September and December 2008. The present results indicate that P. expansa female body size can be estimated based on her tracks. Larger females leave larger foot tracks in the sand and have larger clutch sizes with larger clutch mass than smaller females. Female carapace width and body mass can be considered reliable variables in order to estimate clutch size and total clutch mass for the specie. Larger females should be protected because as they respond for most of the annual population recruitment