One of the commonest kind of solitary bee on the wing this month is the “Nomad” Bee. Often mistaken for small wasps, these tiny bees are cleptoparasites – or cuckoo bees.
Female Nomad bees search for solitary bee nesting burrows and while the host bee is out foraging, they enter the nest and lay an egg in a unfinished egg cell wall. The host species continues to lay eggs and stock the nest with pollen before sealing it. When the Nomad grub hatches out, it then destroys the host eggs or larvae with its large mandibles, and eats the food store which had been provided by the host bee.
There are over 30 species of Nomad bee in the UK (10+ in Guernsey.) Many only prey on one species of solitary bee, while others will use several species. Most have black and yellow banded abdomens, but several are red and black. They are almost hairless as there is no requirement to carry pollen and they have thicker exoskeletons to withstand conflict with the host species.
These inconspicous insects are widespread, and can be found in gardens, on cliff paths – in fact anywhere where their host solitary bees are building nests, often in big numbers.
Despite the fact that Nomad bees have no requirement to collect pollen, they do visit flowers to feed on nectar, and are therefore important pollinators.