chapter  11
4 Pages

Who Lives, Who Dies, and Why?

ByMichael J. Lannoo, Rochelle M. Stiles

Every breeding season at Nate’s and Cattail Ponds, Vanessa (RMS) generated a census of the number of females who had bred there, and how big they were. She then calculated an average body length for females breeding at each pond. From Vanessa’s and RMS’s data it is clear that the highest mortality in Crawfish Frogs occurs during the tadpole and juvenile stages. Compared with related ranid species, Crawfish Frogs exhibit a low larval and juvenile survivorship, but high adult survivorship. Southern Leopard Frogs, a ranid that breeds at the same time as Crawfish Frogs, and whose spring breeding tadpoles metamorphose at about the same time as Crawfish Frogs, have a maximum life span about half the age of Crawfish Frogs. If a Crawfish Frog can survive the bottleneck of high larval and juvenile mortality, it has a good chance of living a long life.