BUCKLEY, Christine R.; MICHAEL, Scott F.; IRSCHICK, Duncan J.; Tulane University; Tulane University; Tulane University: The effect of hatching timing and substrate type on performance and behavior of a direct-developing frog

The timing of hatching can have profound consequences for juvenile fitness in ectotherms. Potentially fatal threats may create a tradeoff between hatching early to escape risks to embryos and hatching late to delay risks to hatchlings. The degree of development at hatching can affect not only a hatchling�s size, but also its performance and behavior. The direct-developing Puerto Rican frog, Eleutherodactylus coqui, provides an ideal organism with which to study the effects of hatching timing on offspring performance. Male egg defense in these frogs is highly variable, and thus embryos often experience intense predation pressure. In addition, because these frogs hatch as tiny froglets, bypassing the tadpole stage, jumping performance can be measured immediately after hatching. We bred E. coqui pairs in a laboratory setting, induced early hatching, and compared various metrics of jumping performance and behavioral choices for early-hatched and normally-hatched froglets. Here we report that hatching timing does affect hatchling performance, but that froglets modify their locomotor behavior on different substrate types to counteract this difference.