Worcestershire Record No. 27 November 2009 pp. 22-23

Geoff Trevis

Bombus hypnorum, the Tree Bumblebee, derives its name from its natural nesting sites in hollow trees athough in this country it has taken to tit nest boxes in a big way. It is a relative newcomer to Britain which was first recorded in England in 2001 at a site in Hampshire. After an initial lag phase it has spread rapidly north until in 2009 it was found in Northumberland, near the Scottish border. Surprisingly, it has been reluctant to spread westwards and Worcestershire is on the western edge of its current range. This year it has been reported from Worcester, Hanley Swan, Droitwich Spa, Redditch, Tiddesley Wood, Eades Meadow (Fosters Green), Barnard’s Green, Nafford and Knapp and Papermill Reserve at Alfrick. It is important that the recording effort is maintained for this easily recognisable species for our own local interest and, more importantly, to add to the national database being used to study the species as it appears to provide a model for the effects of climate change on aculeate hymenoptera. It is unlikely that there will be further records this year but please keep an eye out for it in 2010 and report any sightings to the Worcestershire BRC. You will be looking for a bumblebee with a red/brown thorax, black abdomen and white tail. Luckily there is no other species likely to cause misidentification.