Age-Related Flower Sampling in Bumblebees: A Survey of Unsuccessful Foragers

Shirrinka Goubitz, Tamar Keasar & Avi Shmida

Naive bumble bees (Bombus terrestris) that did not learn to handle artificial flowers were examined for sampling frequency and duration before giving up. The munber of sample-bouts and the time of each sample-bout were measured, as well as the time in between two subsequent sample-bouts (pauses). This flower-sampling behavior of un successful individual bumble bees was related to the age of the bees, cohort and colony size. Younger bees sampled the flowers more frequently but stayed a shorter time each sample-bout than older bees. The duration of each separate pause was longer for older bees as well. The total sampling-time before giving up tended to be higher for the older bees. For all bees the subsequent sample-bouts showed a decrease in duration, while the duration of each subsequent pause increased. This was possibly caused by a negative re-enforcement by the unsuccessful samples. The higher unsuccessful sample-frequency of the younger bees could beconsidered a part ofa first orientation and learning process of flower handling. Therefore this sampling could influence the future behavior of young bees and might result in a higher capability of handling comlex flowers. Finally it should be emphasized that these results are our first prove of age-related learning and it is suggested that research along this line could result in more evidence of age-related foraging behavior.

May, 1998
Published in: 
Entomologia Generalis 29 (2007), 201-211