Climate Change Drives Bumblebees to Nest in Winter, Conservationists Warn

Bumblebees are starting to build nests in the depths of winter due to climate change, raising concerns among conservationists.

The charity Buglife reported sightings of active worker bumblebees in Aberdeen during the unseasonably mild Christmas period. Normally, these insects hibernate through winter, emerging in spring to pollinate plants.

Buglife’s previous surveys also recorded bumblebees and honeybees across the UK between Christmas and New Year, including in the Highlands. However, the charity warns that early nest-building puts the bees at “high risk” of failure due to a lack of flowers for nectar and pollen and the potential for a return to colder weather.

The charity’s Paul Hetherington said: “In 2019 Buglife ran a bee survey over the Christmas to New Year break and were amazed at the results with honeybees and bumblebees found from Jersey through to Thurso.

“This year one of my colleagues based in Aberdeen spotted active worker bumblebees over the Christmas break.

“The fact that there are active workers means not only have the queens awakened from hibernation but they have gone to the extent of starting new nests.”

Paul Hetherington noted that during a 2019 survey, bees were spotted as far afield as Jersey and Thurso over the festive period. He highlighted the precarious situation for bees, emphasising that the combination of flower scarcity and wintry conditions could lead to nest collapse and bee mortality.

He added: “If this happens there will be no new queens produced meaning far fewer to emerge in spring further feeding the known decline in bumblebees.”

Scientists have linked climate change to widespread losses of bumblebee populations worldwide. The insects play a crucial role as pollinators, supporting ecosystems and agriculture.

This winter’s unusual conditions also affected other invertebrates, including ticks. These parasitic, spider-like creatures, typically active from early spring to late autumn, were found in Inverness and other areas during the Christmas period. One tick was spotted in woodland near Ness Castle on 28 December. Unlike bees, adult ticks do not hibernate, instead seeking shelter in long vegetation to survive low temperatures.

Ticks can transmit Lyme disease, a bacterial infection that causes a range of health issues in humans.

The charity Lyme Disease Action described the winter activity of ticks as a concerning development.

Mr Hetherington said: “This means that they are still potentially active and the period around 28 December was relatively warm for the time of year, a likely consequence of climate change is increased periods of tick activity in the same way that bumblebees have been spotted on the wing across Scotland this December.”

The findings underscore the broader impacts of climate change on wildlife, disrupting natural behaviours and creating new challenges for conservation.