Polarization Sensitivity in Amphibians

Abstract

Adult amphibians perform periodic migrations and homing between the sites of reproduction, nutrition, shelter and hibernation. The presence and the extent of site fidelity vary considerably among different amphibian species, and the homeward orientation seems to be restricted almost entirely to the area of previous migratory experience (Sinsch 1992). Several species of amphibians are able to orient by means of celestial cues, e.g. the toad Bufo fowleri (Ferguson and Landreth 1966), newts (Landreth and Ferguson 1967), the bullfrog Rana catesbeiana (Ferguson et al. 1968), the southern cricket frog Acris gryllus (Taylor and Ferguson 1970) and the tiger salamander Ambystoma tigrinum (Taylor and Adler 1978). The predictable effects of clock-shift on the directional choice of amphibians using the celestial compass prove that they possess a circadian clock for the necessary time compensation of celestial rotation (e.g. Taylor and Ferguson 1970). In nocturnal amphibians, star or lunar compasses have been demonstrated (e.g. Plasa 1979). However, the optical cues guiding the celestial orientation and the underlying perceptual systems have not been identified yet in most cases.