Oxygen Consumption and Organ Growth in Sooty Tern (Sterna fuscata) Embryos

Abstract

data were obtained for the Sooty Tern. There are some similarities between the eggs of the two species. The sequence of events during pipping, which had an important effect on organ growth in shearwater embryos, is similar in terns and shearwaters (Pettit and Whittow 1983, Whittow 1985). The maturity of the hatchling is also similar; both are designated to be semiprecocial (Pettit et al. 1984). However, there are also differences between the two species as well. The incubation period of the Wedge-tailed Shearwater's egg, but not that of the Sooty Tern's, is prolonged (Whittow 1980). Incubation temperature is 3?C higher in the Sooty Tern (Rahn et al. 1976). Incubation also is different; the Sooty Tern lays its egg directly on the ground whereas the shearwater's egg is protected by the burrow in which it is laid. Thus, there were reasons to expect similarities in embryonic organ growth between the two species, but also grounds for anticipating differences. So little