Differences in rainfall between years influenced the proportions of different types of nesting habitats of Caiman crocodilus yacare available near water bodies in a region of intermittent rivers (Campo Dora Ranch). In contrast, rainfall had little effect on the proximity of nesting habitat to water bodies in a region of isolated lakes (Nhumirim Ranch). There was a strong positive correlation between female body size and clutch size Snout-vent lengths of females on Campo Dora Ranch were significantly larger than those from Nhumirim Ranch which probably accounts for the larger mean clutch size than in the region of isolated lakes. Hatchling size was correlated with egg size, but there was no relationship between egg size and female size or egg size and clutch size.
