This ivy bee (Colletes hederaea) was photographed in the park in November but has just now been positively identified by an entomologist; not only a new name for our species lists but a relative newcomer to the UK.
The species was first reported from Dorset in 2001; since, it has spread along the southern coast and north through Hampshire, Somerset and Wiltshire. By 2014 it had reached Shropshire and this year has been recorded in Norfolk and South Wales.
It is a late-emerging pollen specialist that forages in flowering ivy, late in the year when competition is scarce. Its rapid colonisation of Britain is unusual because bees generally return, generation after generation, to traditional nest sites and have rarely been seen to cross major geographical barriers. The species has shown highly successful dispersal behaviour.
Climate change may have played a part in its spread. Ivy reproduces vegetatively in colder climates but in recent years, in our warming summers and mild autumns, it has flowered more frequently and for longer, giving the adult female bees time to rear exceptionally large broods of pupae. Population density can trigger unusual dispersal behaviour in a species.
The bee’s rapid expansion also seems to have allowed the front edge of the spreading colonisation to outrun several of its predator species, particularly those that parasitise their nests.
In Britain, at the moment, the ivy bee has a clear run: plentiful food and nesting sites, little competition, a long breeding season and an absence of predators and parasites. It will be interesting to see how far north the species will spread,
Pictures by S Humphries