Solar incubation cuts down parental care in a burrow nesting tropical shorebird, the crab plover Dromas ardeola

Abstract

We describe an unknown mode of solar‐assisted egg development in the crab plover Dromas ardeola, a shorebird that breeds in self‐excavated burrows. The insulating properties of the nest burrow and the intense solar radiation allowed egg development at near‐optimal temperature (35.2°C±0.2) and humidity (60.2%±4.4), allowing a very low incubation attendance by the parent birds (28.3% of time, with recesses lasting up to 58 h). Crab plovers did not abandon completely parental incubation, possibly because of the need to turn their egg, and because the slight warming provided by parents (0.8°C) may improve hatching. This is the first case of solar assisted incubation in a species unrelated to the Megapodiidae, the only birds known to develop their eggs without contact incubation.