Individual study: Bumblebees Bombus terrestris from reintroduced colonies prefer to forage at least 100 m from their nest sites in Vestby, Akershus, Norway
Dramstad W.E., Fry G.L.A & Schaffer M.J. (2003) Bumblebee foraging - is closer really better? Agriculture, Ecosystems and Environment, 95, 349-357
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
Reintroduce laboratory-reared bumblebee colonies to the wild
A trial with three laboratory-reared colonies of B. terrestris introduced to an agricultural landscape in Vestby, Norway (Dramstad et al. 2003) found that greater numbers of marked bumblebees from the colonies foraged on a 210 x 2 m sown strip of phacelia Phacelia tanacetifolia when the nests were moved more than 100 m away from the strip (18.3 marked bumblebees/210 m transect) than when they were placed right next to it (11.5 marked bumblebees/ 210 m transect).
Plant dedicated floral resources on farmland
Dramstad et al. (2003) recorded numbers of bumblebees visiting a single 2 m x 210 m sown strip of phacelia, in Vestby, Norway, in 1994. They recorded a peak of 237 bumblebees on the strip (0.6/m2) on 17 July, which gradually declined to 93 bumblebees on the strip (0.2/m2) on 28 July.
Plant nectar flower mixture/wildflower strips
A small-scale study in 1994 in Vestby, Norway (Dramstad et al. 2003) found the number of bumblebees Bombus spp. visiting a single 2 x 210 m strip sown with phacelia Phacelia tanacetifolia peaked at 237 individuals (0.6 bumblebees/m2) on 17 July, and gradually declined to 93 bumblebees (0.2/m2) on 28 July. Maximum numbers of honey bees Apis spp. foraging on the phacelia strip were recorded on 14 July with 3739 honey bees (9.0/m2), honey bee abundance declined steadily after 18 July with the lowest numbers recorded on 28 July (22 honey bees). The strip was sown in May 1994 along the boundary of a cereal field and a ‘habitat island’ (area of semi-natural habitat within the farmed landscape). Bees were surveyed over a three week period (5-28 July).