A Novel Method for Estimating Nest Density in Bumblebee Populations from Molecular Genetic Markers

Bumblebees ( Bombus spp.) are important pollinators of both wildflowers and crops. In recent year, declines of population size have been reported in many Bumblebee species in various countries. In order to design effective conservation plans, nest (colony) density in a habitat is an essentially important information. In the present study, a novel method for estimating nest density using molecular genetic markers was proposed, by extending the concept of neighborhood size in population genetics. The proposed method was compared with the conventional method used in previous studies by applying to microsatellite data of Bombus hypocrite sapporoensis . Based on the obtained estimates of nest density, advantage and disadvantage of the two methods were discussed. An interpretation of estimate obtained by the proposed method was also presented from a viewpoint of conservation genetics.