Pollen collectors

All nest-building bees collect pollen to feed their offspring. However, how they do this and how they transport the pollen to the nest varies from species to species.

"Crop collectors" eat the pollen and regurgitate it in the nest. Honey bees and bumblebees collect it on smooth surfaces lined with hair bristles on their widened hind legs. Solitary wild bees usually use special hair brushes to transport pollen. They are typically located on the hind legs in species that nest in the ground, and on the underside of the abdomen in species that nest above ground.

The small but common Heriades truncorum collects pollen from composite flowers directly into this "abdominal brush" with conspicuous bobbing movements. For example, they can be easily observed doing this on the dyer's chamomile.

Image captions:
Heriades truncorum visits yellow composite flowers in midsummer.
Dyer's chamomile [Cota tinctoria (L.) J.Gay].
Narrow, tubular cavities about 3.5 mm in diameter serve as nesting sites. Intermediate walls and closure are made of resin.
Male (left) and female (right) of Heriades truncorum.

English translation of the information panel in the Botanical Garden. Original German text: Dr. Barbara Ditsch, Mandy Fritzsche