East Sussex downland bees and wasps get a health check
For six years between 2003 and 2008, over 100 site visits were made to fifteen chalk grassland and chalk heath sites within the South Downs of Vice-county 14 (East Sussex). This produced a list of 227 bee and wasp species and revealed the comparative frequency of different species, the comparative richness of different sites and provided a basic insight into how many of the species interact with the South Downs at a site and landscape level.
The report is now available from the website of the Bees, Wasps & Ants Recording Society
The 227 species of bees and wasps recorded included many rarities. Most notable amongst these was a solitary bee called Halictus eurygnathus which had not been seen in Britain since 1946 and was considered nationally extinct. But reports of its demise were clearly premature as it was eventually found at seven sites. Females rely very heavily upon Greater Knapweed as a pollen source, and with this new information, it should be possible to conserve it and hopefully help it to spread.
The study also revealed the important role that arable field margins, flowery fallow fields and blossoming shrubs such as Blackthorn play in supporting bees on the downs. One of Britain’s rarest mining bees Andrena niveata was found to forage primarily from flowers of Charlock and Hedge-mustard at the edges of Rape crop, a relationship that had not been noted anywhere previously. But the study also revealed that some species are in trouble in East Sussex including Britain’s largest mining bee Andrena hattorfiana which forages on scabiouses. The study also failed to rediscover Culluman’s Bumblebee which was last recorded in Britain in 1926 and seemingly had a good population in the Seaford area.
The work was carried out by Warwickshire entomologist Steven Falk, who also recorded the flies present, which will be subject to a future report. Hopefully the study will help the various landowners and land managers of the South Downs to promote these important insects, especially given the growing international concern regarding declining pollinators. Steven is also keen to encourage local naturalists to investigate less popular insect groups of the Downs.
Explore the data held for some of the species above through the NBN Gateway:
Image of Andrena niveata courtesy of Steven Falk