Bees and Ben Lawers

Bees are well known as plant pollinators, and the floral diversity of Ben Lawers provides an array of habitats for them.

Of the 270 British bee species, many of us are familiar with the honeybee (Apis mellifera) and with bumblebees. We’re pleased that 9 of the 24 British bumblebee species have been recorded at Ben Lawers, including the rare bilberry bumblebee (Bombus monticola) and the broken-belted bumblebee (Bombus soroeensis). Most of these species are social, living in colonies.

Less familiar are the species that comprise the remainder of the British bee fauna, collectively referred to as solitary bees. These generally create individual nests, although they can be grouped close together. Many burrow in the ground, in dry, sunny areas that warm up quickly, so their presence can be detected by looking for the entrance holes, which often have small mounds of soil next to them. Their flight periods are associated with the flowering of the plants on which they rely for pollen and nectar. They can be quite tricky to identify, which means few have been recorded on the reserve.

Local bee expert Anthony McCluskey used lockdown to search for solitary bees along the Morenish Woodland Trail. He suspected its south-facing aspect and areas of bare soil would provide good nest sites. Since many bee species are willow (Salix spp.) specialists, the restored woodland would provide good foraging habitat. His instincts proved correct, and he made some exciting finds.

Several of the species he found were mining bees. In April, he spotted several female Clarke’s mining bees (Andrena clarkella) foraging on willow catkins after spending the winter as freshly emerged adults in sealed natal cells. They are very hairy, red on the thorax and black on the abdomen, and have pollen baskets not just on their legs but also on their abdomen. They can form large nesting aggregations. Although a widespread species, there are almost no records in the central Highlands. However, recent finds in Glen Lyon too suggest it is maybe more prevalent here than currently known.

Flying in early May were two other willow-feeding species. The northern mining bee (Andrena ruficrus) also uses dandelions (Taraxacum spp) as a nectar source and can form small nesting aggregations. The males are described as rather nondescript, which may explain why there are very few records in the central Highlands, making this a good find.

The orange-tailed mining bee (Andrena haemorrhoa) is a large, distinctive species with orange hairs at the tip of a mostly shiny black abdomen. It also feeds on pollen from other plants including hawthorn (Crataegus monogyna) and herbaceous plants such as dandelions, coltsfoot (Tussilago farfara), greater stitchwort (Stellaria holostea), wood anemone (Anemone nemorosa) and buttercups (Ranunculus spp). This is reflected by its flight period lasting into July. It nests singly or in loose aggregations and is fairly ubiquitous.

As their name suggests, females of the tormentil mining bee (Andrena tarsata) collect pollen from tormentil (Potentilla erecta) so this species is found in heathland, occurring into late August. They nectar at brambles (Rubus spp), harebell (Campanula rotundifolia), wild angelica (Angelica sylvestris) and yarrow (Achillea millefolium). There are probably fewer than 100 records in Scotland, but they are well-distributed in the uplands.