11 June 2024
Concerns mount over the dwindling population of one of England and Wales most threatened bumblebees in Somerset, the Shrill carder bumblebee.
The Shrill carder bumblebee (Bombus sylvarum) is a distinctive bumblebee which can be identified by its pale grey-yellow colouring, black band of hair between the wings and reddish-orange tail, and a noticeably high-pitched buzz.
This rare bumblebee now only exists in five isolated population areas: the Thames Estuary, Somerset, the Gwent Levels, Kenfig–Port Talbot, and South Pembrokeshire and is a priority species in England and Wales following significant declines since the 1950s.
The Bumblebee Conservation Trust’s Save Our Shrills (SOS): Somerset project aims to halt this decline.
Guided by the Shrill carder bumblebee conservation strategy launched in 2020, the Trust is collecting scientific evidence on this rare bumblebee through the Bumblebee Conservation Trust’s BeeWalk scheme, essential for examining changes in populations and their distribution, and for targeting conservation action.
Data shows the Somerset population does not appear to be thriving in a manner equivalent to the Thames Estuary with only 25 individual bumblebees recorded in 2023, 21 of which were found on only one site. It is thought that the population on Salisbury Plain may already have gone extinct. A survey in August 2023 yielded no records.
Jo Chesworth, Senior Project Officer at the Bumblebee Conservation Trust said “The project is working with landowners and farmers to provide advice on creating and restoring flower rich habitat which is connected up across the landscape, essential for the survival of this rare bumblebee. Loss and fragmentation of habitat is a key threat isolating Shrill carder bumblebee populations and the small surviving populations make this rare bumblebee vulnerable to inbreeding and loss of genetic diversity, further increasing the risk of local extinctions. Encouragingly, first records for the Shrill carder bumblebee in Somerset have been received for 2024, providing reassurance they are still present in the county”.
The Shrill carder bumblebee is a late emerging species from May and males and new queens will be seen foraging late into August and September which makes it vulnerable to loss of flowering habitat in mid-summer. Late cut meadows, field edges, hedgerow margins can help provide this essential forage.
