What caused the mass bumblebee deaths at Golspie? Experts baffled by piles of carcasses on scenic stretch
The sad sight of hundreds of dead bumblebees along the promenade at Golspie has baffled and concerned local conservation experts.
On Friday (May 31), a multitude of the insect carcasses were observed along a scenic stretch next to the Bay of Sutherland with many clumped together on or beside pathways creating a shocking sight for locals and visitors alike.
One Golspie resident said that a garden along Murdo’s Lane, which backs onto the coastal stretch, had been filled with dead bees as well. Another woman wondered if “some type of pesticide” had led to the mass death.
The images presented here were shared with High Life Highland countryside ranger Paul Castle who is based in Caithness and recently penned an article about bumblebee deaths he encountered while walking along a road at Dunnet Bay.
“I counted eight dead white-tailed bumblebee (Bombus lucorum) workers, which had obviously been hit by passing vehicles,” he wrote.
The article continued: “White-tailed bumblebees are one of our more common species and, looking at this one short 200m section of path, I was glad that’s the case. Scale this scene of devastation up to a county or national level and the mind begins to boggle.”
Mr Castle said he found the Golspie images very “worrying” and was unsure what had led to the bees dying en masse. “As I don’t know the area and what, if any, particular habitat management is happening on site, I can’t guess what may have caused this,” he added.
He suggested we contact the governmental advisory body NatureScot which investigates and comments on environmental matters and has an office in Golspie.
David Mackay, operations manager (north) at NatureScot, said that “it’s not something I’ve ever come across before” and agreed to send some of the dead bees to the Bumblebee Conservation Trust.
He also shared information from the NatureScot website on the ‘natural mortality of bumblebees’.
The information reads: “The sight of large numbers of dead or dying bumble bees on the ground may be alarming, but the phenomenon is fairly common and usually not related to human actions.” It then goes on to state the various reasons for the mass deaths which include the relatively short lifespan of bumblebees (four weeks).
“All bees chuck out debris and dead bees from their nest to maintain hygiene, so a cluster of dead bumblebees could mean that there is a nest nearby, even though you may not see it,” it further states.
Other reasons for the phenomenon include a sudden drop in temperature, flooding, bird predation and parasites. “Bumble bees are victims of several viruses, bacteria and other microorganisms that debilitate and often kill their hosts.”
Katy Malone, conservation projects manager (Scotland) of the Bumblebee Conservation Trust, will be receiving specimens from NatureScot and said it was “a concerning incident”.
If pesticides are the root of the problem then laboratory analysis of the dead bumblebees would, hopefully, uncover the evidence but this will take some time. She said there may not be any conclusive result for the cause of death.
Ms Malone added: “Multiple bumblebee deaths at this time of the year is a real cause for concern. We might expect mortality late in the summer as the colonies naturally die off, and sometimes birds will predate them, but neither of these common causes fit with the circumstances that have been reported to us.
“We have arranged for a sample of the dead bees to be sent off for laboratory testing, but right now we can only say that the cause of this mass mortality of bumblebees is unexplained.”
