British Wildlife Wiki
Queen dave goulson

Queen Carder-bee by Dave Goulson with thanks to the BBCT

Bombus pascuorum, the Common Carder-bee, is a species of bumblebee belonging to the family Apidae subfamily Apinae tribus Bombini.

They are present in most of Europe in a wide variety of habitats such as meadows, pastures, waste ground, ditches and embankments, road, field margins, as well as gardens and parks in urban areas and forests and forest edges.

Theese bees reach a body length of 15–18 millimetres (0.59–0.71 in)(Queen), 9–15 millimetres (0.35–0.59 in)(worker) or (drone). Their wingspan is 28 to 32 mm (Queen), 20 to 28 mm (worker) or 24 to 27 mm (drone).

The thorax is yellowish or reddish-brown. The first 4 abdominal segments have grayish hair, while the fifth and sixth tergite hairs are yellowish or reddish brown. However the species is quite variable in color.

The head is medium long, the snout is long and reaches a length of 13 to 15 mm (Queen), 12 to 13 mm (worker) or 10 to 11 mm (drone).

Queens occur from early April to mid-May, workers at the end of April / early May to mid-October. Young queens and drones can be found from mid-August to late October. When the Queen search for suitable places to nest, they fly just above the vegetation, for example on forest edges, investigating cavities like holes in the ground or niches in dead wood and grass. The nests can be created above ground and underground, preferably in old mice nests, but also in bird nests or in barns and sheds.

First the queen collect moss, grass, and form a small, hollow sphere, whose walls are partly bonded with wax and sealed off. Then, it is made a large bowl of brown wax of about five millimeters, which is filled with pollen. After that 5 to 15 eggs are deposited, this cell is closed. Another 20 mm high cup is filled with nectar, which serves as its own food reserve for bad weather days. After three to five days the larvae hatch to feed on pollen. After about a week the larvae are mature.

The adult bees, owing to the initially poor supply situation, are relatively small, reaching only about half the body length of the queen and have no functioning ovaries. Later hatching bees are much larger. The additional nesting and brood care is dedicated solely to the Queen, which no longer leaves the nest. From August, rarely before, the first fully developed females, together with drones, are ready. Drones hatch from unfertilized eggs.

The nest in August reach the maximum population size from 60 to 150 individuals. It has a diameter of up to 15 to 20 centimeters. Shortly after the peak, the population quickly decreases. With the queen the entire nest dies, usually in September. Occasionally, people survive until October / November. Only the last-hatched females survive and mate with males. Then they go in search of a safe place for hibernation.

This polylectic bees mainly feed on Nettles (Urticaceae), Genuine Motherwort (Lamiaceae), Himalayan Balsam (Balsaminaceae), Cabbage Thistle, Knapweed (Asteraceae), Vetch, Red and White Clover (Fabaceae), Monkshood (Ranuncolaceae), fruit trees, etc.