Hs. Arathi et al., Ethology of hygienic behaviour in the honey bee Apis mellifera L-(Hymenoptera : Apidae): Behavioural repertoire of hygienic bees, ETHOLOGY, 106(4), 2000, pp. 365-379
Hygienic behaviour performed by middle-aged worker bees is an important int
ranidal task in colonies of the honey bee Apis mellifera (L.). It comprises
detecting diseased brood in the larval and pupal stages and removing all s
uch infected brood, thereby decreasing the incidence of infection. Hygienic
behaviour consists of two task-components: uncapping cells and removing th
e cell contents. The aim of this study was to observe bees performing hygie
nic behaviour to determine their age at performance of the behaviour and to
describe their behavioural repertoire. The bees performing hygienic behavi
our were middle-aged bees, younger than foragers. In the colonies where the
behaviours of individual bees were observed, all bees performing the hygie
nic behaviour were seen to exhibit both the components, though at different
frequencies. One behavioural class performed the task of uncapping cells a
t higher frequencies than the task of removing cell contents, while another
class performed both tasks to the same extent. While these two classes had
higher frequencies of the tasks comprising the hygienic behaviour but lowe
r frequencies of other common behaviours in their repertoire, a third class
of bees included those that performed all behaviours in their repertoire a
t similar frequencies. There was no difference in the ages of the bees in t
hese three behavioural classes. These results suggest that there is no evid
ence of task partitioning among bees performing the hygienic behaviour. The
segregation observed could, however, be based on their response thresholds
to the stimulus and/or on their ability to discriminate the various cues e
manating from the dead brood.