
Buff-tailed Bumblebee Bombus terrestris
Flight season: Early February to October but in cities populations can overwinter as active colonies.
Flowers visited: A wide variety depending on the season but in the summer workers are limited by their fairly short proboscis (tongue) averaging 5.8 mm. However they do have a trick up their tiny six sleeves (see below)…
Nesting preferences: Ground nesters. B. terrestris queens will predominantly use old small rodent burrows such as voles or mice. It has been shown that the queen actually prefers her nest to smell of small rodent before using it! Very large colonies with up to 500 individual bees.
Status: One of the UK’s commonest bumblebees but scarcer in the uplands.
Parasites: The Vestal cuckoo bumblebee Bombus vestalis.
Similar species: Queens are distinctive but the White tailed bumblebee, B. lucorum, and B. terrestris workers need careful examination.
Description: Easily separated as a queen from the similar Bombus lucorum, the buff tailed bumblebee has more dirty yellow bands with a 'buff' tail. They also seem to be more common which is useful. In workers the differences are far harder to discern as the tail is far whiter. If you can get a good look at the tail there may be a coffee coloured rim around the top or just a few buff hairs indicating B. terrestris. Again, the yellow bands are dirtier than B. lucorum's. The differences between males in B. lucorum and B. terrestris is easy as the B. terrestris do not have yellow hair on their face. However, this makes it more difficult to tell between workers and males and the best thing to do is count the antennal segments (13 for male, 12 for female).
Where to see them: Probably the most common bumblebee in the valley and can be found everywhere.