Individual study: Underground and 'false underground' nest boxes more frequently occupied by queen bumblebees Bombus spp. than surface nest boxes in southern Alberta, Canada
Hobbs G.A. (1967) Obtaining and protecting red-clover pollinating species of Bombus (Hymenoptera: Apidae). The Canadian Entomologist, 99, 943-951
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Provide artificial nest sites for bumblebees
A trial of 1,233 surface boxes, 465 underground boxes, 500 false underground boxes and 100 above ground boxes in areas of mixed woodland and grassland in southern Alberta, Canada, from 1961 to 1966 (Hobbs 1967), found underground and false underground boxes were more often occupied by bumblebees (approximately 58% and 48% respectively) than surface boxes (approximately 26%) or above ground boxes attached to tree trunks (35%). False underground boxes were at the surface, but with a partially buried entrance pipe giving the appearance of a subterranean nest.