Microclimate of the nest and egg water loss of the eider Somateria mollissima and other waterfowl in Spitsbergen

Abstract

Temperature gradients in the nest and within the egg. nest humidity as well as eggshell conductance and rate of egg water loss of the Eider Somareria mollissrma and other uaterfowl were studied at Ny-Alesund. Spitsbergen (78%" latitude). These studies suggest a specific interrelationship between eggshell conductance and maintenance of an appropriate temperature and humidity environment of the nest. resulting in an egg water loss rate which is optimal for hatching success. In spite of low ambient temperatures of less than 3°C and very low absolute humidities of less than 4 torr (similar to those found in hot deserts). the nest's microclimate and rate of mater loss were similar to those reported for nests and eggs in temperate climates.