chapter  10
2 Pages

Feast or Famine

ByMichael J. Lannoo, Rochelle M. Stiles

The reason the body mass indices of Crawfish Frogs change across years is that their bodies respond to environmental conditions within years. In addition to insects, Crawfish Frogs likely also feed on smaller frogs such as Chorus Frogs, Spring Peepers, Cricket Frogs, and the newly metamorphosed juveniles of Southern Leopard Frogs and Green Frogs; they could also be cannibalistic and feed on juvenile Crawfish Frogs. Crawfish Frogs must gorge themselves when they can, because they never go completely quiescent, and their most energetically demanding time of year—breeding and its associated behaviors—occurs at the tail end of their six-month fast. Southern Crawfish Frogs should be able to feed most of the year, which would suggest they should have larger body sizes. The observation suggests metabolic demands are higher in warmer climates, and that life in this biochemical fast lane hampers attempts by Crawfish Frog adults to stockpile energy reserves.