Parental Reactions To Young in Sticklebacks (Gasterosteus Aculeatus L.)

Abstract

Three-spined sticklebacks readily eat conspecific young. Only when males have one or more clutches of eggs in their nest, do they develop a tendency to retrieve young and carry them to the nest. This tendency becomes evident between the second and the sixth day after egglaying and fertilisation, but most commonly on the third or fourth day. Even quite hungry males retrieve young in this period of their breeding cycle. However, if such males have previously learnt to accept young as food, they eat young also in this period. Sudden satiation of such males in the period concerned shows that the tendency to retrieve was only masked by the habit of eating young. Presumably retrieving is released by rather specific stimuli, for even young of the related ten-spined stickleback are only seldom retrieved and with reluctance. The experimental results are related to more natural situations and to suggestions and data in the litterature.