MORPHOMETRIC VARIATION AND ITS EFFECT ON REPRODUCTIVE POTENTIAL IN FEMALE COLOMBIAN SLIDER TURTLES (TRACHEMYS CALLIROSTRIS CALLIROSTRIS)

Abstract

We evaluated morphometric variation and reproductive effort in Trachemys callirostris callirostris females from nine populations in the Mompos Depression of northern Colombia. Two hypotheses were evaluated: (1) phenotypes of nesting females co-vary according to geographic distances among sites and/ or specific environmental conditions at each site, and (2) female body size influences their reproductive potential and offspring characteristics. Populations were shown to differ in both mean female body size and body shape, with differences more related to local habitat characteristics than to geographic distances among sites. Larger females occurred in sites with higher annual precipitation and lower hunting pressure. Female size was highly correlated with clutch size and mass. Although habitat characteristics affected female size, habitat alone was not a predictor of reproductive potential. Specific habitat conditions and hunting both influence female phenotypes in this region and thereby also influence key demographic parameters, which have clear conservation implications for this highly exploited species.