Costs to foraging bumble bees of switching plant species

Publisher Website
Google Scholar
Abstract
Many pollinators tend to move between flowers of the same species of plant even when flowers of other species are available. Reasons for this behaviour (known as flower constancy) are unclear. One possible explanation (proposed by Darwin) is that flower handling methods learned on one plant species interfere with previously learned handling methods of other plant species. Darwin's hypothesis was tested by measuring the constancy of bumble bees (Bombus fervidus) foraging in the field and looking for evidence of interference (increased handling times and flower handling errors) when bees switched among four species with relatively simple flowers (Prunella vulgaris, Trifolium pratense, T. hybridum, and Vicia cracca) and two species with more complex flowers (Aconitum napellus and Impatiens capensis). Bees foraging on simple flowers showed no tendency towards flower constancy, and switching between species did not increase handling times or handling errors. Foragers displayed strong constancy when visiting the species with more complex flowers and there was also some evidence of increased handling times and error frequencies following switches. However, the time costs of switching were small (about 1 s over the first flower visit after a switch) and are unlikely to account for flower constancy by bumble bees foraging under natural conditions.

This publication has 0 references indexed in Scilit: