Habitat-contingent reproductive behaviour in radio-implanted salamanders: a model and test

All tiger salamanders, Ambystoma tigrinum, entering a small pond in New York state were given radio-implants and tracked throughout breeding to determine whether reproductive behaviour in nature differs from that described in laboratory studies. I formed an extended model of adult reproductive behaviour that included male and female strategies and differential use of habitat components in the breeding pond, and then tested four key predictions regarding adult movement using the sequence of positions of all salamanders between pond entry and exit. An unexpected, female-biased sex ratio during most courtship activity led to departures from the predicted behaviour, but in all other respects the behaviour of the males and females followed from the predictions. Apparent mate scanning in clear water, and weather assessment in pond-edge shallows just prior to emergence, are new indications for caudate amphibians. Copyright 1998 The Association for the Study of Animal Behaviour. Copyright 1998 The Association for the Study of Animal Behaviour.