Et tu, bee?
A rare species of bumblebee that stages a coup every time it wants to breed, has been found living for the first time on the Hebridean island of Oronsay.
The aptly name cuckoo bumblebees are ‘antisocial’ bees that rely entirely on the activities of their more sociable counterparts to reproduce. Females launch sneak attacks at the nests of other bumblebees (often killing the resident queen), lay their eggs, and fool the worker bees into taking care of her offspring. It’s a strategy that works so well that the cuckoos are wholly dependent on their hosts for survival.
This particular species, known as the field cuckoo bumblebee (Bombus campestris), was last recorded in Argyll in 1990, and is more often seen on the east coast of Scotland. It is not a common bee in Scotland, and south of the Border there are suggestions that its numbers may be going down.
It was discovered by Nicky Redpath, who is currently researching the restoration of degraded machair and bumblebee habitat in a project co-funded by the Bumblebee Conservation Trust (via Scottish Natural Heritage), the University of Stirling, and RSPB Scotland. She has been studying sites on Oronsay for three years.
Nicky said: “Cuckoo bumblebees are remarkable creatures but can be hard to identify, so they’re often under-recorded. Mike Peacock, who manages Oronsay for the RSPB, and I have spotted 10 males – of a bright yellowish form that seems unique to Scotland – just in the past week or so. We’re guessing that they’ve come from the nest of a common carder bee, a gingery-brown bumblebee which is a regular visitor to gardens everywhere, and the usual host for the field cuckoo.
“The males of this species tend to just hang around drinking all day and don’t do any work around the nest, so you might say they’re typical men! However, it does make them quite easy to track down at their ‘nectar bars’.”
All the bees sighted on Oronsay may have come from a single nest, suggesting that a pioneering female found her way there this spring. But there is also a chance that there is an existing population on the island that has never before been recorded.
Bob Dawson, of the Bumblebee Conservation Trust, said: “At a time when our bee numbers are rightly giving cause for concern, the discovery on Oronsay of such a scarce and unusual species for Scotland really is a great find. We’ve had only had a handful of reports this year, all from the east. The bees were seen feeding on common knapweed, which is a good flower to plant in your garden if you’re looking to encourage bumblebees. Other flowers that are good for cuckoo bumblebees are thyme, white clover and cotoneaster.”
Story from RSPB