Making good choices with variable information: a stochastic model for nest-site selection by honeybees

Abstract

A density-dependent Markov process model is constructed for information transfer among scouts during nest-site selection by honeybees (Apis mellifera). The effects of site quality, competition between sites and delays in site discovery are investigated. The model predicts that bees choose the better of two sites more reliably when both sites are of low quality than when both sites are of high quality and that delay in finding a second site has most effect on the final choice when both sites are of high quality. The model suggests that stochastic effects in honeybee nest-site selection confer no advantage on the swarm.

Figure 1

Results for two competitions between two sites, one of fixed quality and another with quality given on the horizontal axis. The fixed site has (a) and (b) R₀^f=2.3, α=0.8 (good quality) and (c) and (d) R₀^f=1.3, α=0.44 (poor quality); β=0.33 throughout. In (a) and (c), results are shown for when the fixed site is selected (dashed line) and when the varying site is selected (solid line).

Figure 2

Percentage of time that a site discovered second will be selected, against delay in discovery of the second site. (a) Upper line, both sites mediocre; lower line, both sites good. (b) One mediocre site and one good site: upper line, good site discovered second; lower line, mediocre site discovered second.