RISK-SENSITIVE FORAGING IN HONEY-BEES - NO CONSENSUS AMONG INDIVIDUALS AND NO EFFECT OF COLONY HONEY STORES

Risk-sensitive foraging theory predicts that animals under energetic stress will prefer variable over constant food resources as a means of avoiding starvation. The foraging worker honey bee from a colony deprived of food should prefer to feed on variable flowers. Individual bees were given repeated binary choices between variable (10% and 30% mg solute/mg solution) and constant (20% mg solute/mg solution) sucrose concentrations delivered in plastic flower tubes of different colours. Sucrose concentration, rather than sucrose volume, was varied so that bees feeding on either constant or variable flowers would experience equal mean sucrose concentrations (20%) and nearly identical (on average within 0·04 J/s) net rates of energy gain. Honey combs were removed or added to a colony to alter the colony's energy state. There was no difference between the preferences of bees from colonies with large amounts of honey and those from colonies with small amounts of honey. Fifty-three per cent of the 9775 flower visits made by 40 bees were to constant flowers. Because of the large number of foraging bees in the colony and the large number of flower visits that individual honey bees make during each foraging trip, the colony achieves close to the true mean of variable resources. Hence, honey bees are little affected by the variance of resources. © 1993 The Association for the Study of Animal Behaviour.