While the sun shines and the rain is not too heavy, bumblebees will be around where there are flowers that need to be pollinated and food stores that need to be filled. They carry on regardless of what we are worrying about because they have an agreement with flowers that is beneficial to both parties, an arrangement that evolved over millions of years. Most colonies will now be coming to the end of their 6-month life-span with only new queens surviving into the winter. If a new queen does not last the winter in hibernation then there will be one less colony next year and fewer flowers will be pollinated. This will be a downward trend. It can be avoided if we provide loads of pollen and nectar during the autumn so that bees face the winter with full fat reserves.
This month’s bee is the Short-haired bumblebee (Bombus subterraneus). However, you won’t be seeing her in the Thames Valley. She is significant because, although she used to be common in the south of England, she was last recorded at Dungeness, Kent, in 1988. The species was declared extinct in 2000 in the UK. Despite a highly organised science-based project to re-introduce some from existing colonies in Sweden, the attempt has been unsuccessful so far. The project, involving farmers, land-owners, local authorities and local communities, was based on a scheme to restore the habitat that once supported the species.
A similar project aimed at replacing lost habitat in north Kent between Dartford and Deal saw significant increases in the numbers of three of our most threatened species (Moss carder, Brown-banded carder and Shrill carder) as a result of the 10 year period. These projects set up by the Bumblebee Conservation Trust show that habitat restoration can work (but not always) to reverse the slide to extinction of some species.
Currently pollinators are busily foraging on available drifts of Ivy, Dahlia, Nasturtium, Abelia and Caryopteris but they will soon be looking for winter-flowering Heather. Shrubs are increasingly important as the year ends. Bulbs will come into their own as the new year begins.
What we are doing locally is restoring or replacing the essential habitats that pollinators need for their survival. We have seen real increases in the number of bumblebees in our gardens as a result of our growing awareness, and our choice of plants. We can make a difference once we know what the problem is and how to rectify it, but only if we ourselves take practical steps to solve it.
Adrian Doble (Bumblebee Conservation Trust) September 2020