Abstract

The trade-offs associated with maternal provisioning strategies in amphibians are well documented. Relevant studies typically demonstrate that female body size is correlated positively with provisioning of resources to offspring; females may augment offspring resources by increasing the size of the clutch or increasing individual egg size. Alternatively, females may practice one or more alternative strategies, including increasing variation of egg size within the clutch or switching from one strategy to another between breeding events. For this study we examined the trade-off provisioning strategy employed by Red-eyed Treefrogs (Agalychnis callidryas), a species with predator-induced flexibility in hatching age. We recorded the mass of 30 females found amplexed with males in the field, as well as clutch size, individual egg diameter, and total yolk volume resulting from the pairings. Our hypothesis that female mass would be correlated positively with total yolk volume was not supported, nor were most other traditionally expected trade-offs. However, we found that there was a significant difference between the largest and smallest eggs within clutches, and that clutches differed in egg size variability, with larger females tending to produce clutches with less variation in egg size. For the largest females, there was a positive trend between female mass and total yolk volume, and a significant and positive relationship between female mass and total number of eggs. These data suggest that a combination of maternal provisioning strategies may be present in this population of A. callidryas, which is likely an adaptive response to an unpredictable environment.