Homes for Bees - March 2022

Our bees don’t ask much of life: a place to nest, the necessary materials to create that nest, access to water, and a plentiful supply of pollen and nectar.
The gardening group at the Rec have been doing our best to meet those needs. When restoring the beds, we’ve used mostly plants that have the RHS designation ‘Perfect for Pollinators’, as well as creating the wildflower meadow. Most of these plants rely entirely on insects such as bees for their pollination, and they attract and reward them with sugary, high-energy food in the form of nectar. Bees also set out to collect pollen which consists of microscopic grains of plant sperm and is rich in protein The bees form the pollen and nectar into bee bread to fuel the growth of their larvae. However, some of the pollen inadvertently sticks to the hairs on their bodies and legs and as they move from plant to plant, they’re able to pollinate them.
Having provided sustenance with suitable plants over a long flowering season, we’ve turned our attention to creating nesting opportunities. The type of nest varies according to the bee species. There are over 250 species of bees in the UK
Most people are familiar with the social bees, which are either honeybees or bumblebees (26 species), but by far the greatest number of species, are what are called solitary bees. Honeybees are largely domesticated and occupy hives, but the truly wild species, create their own nests.

BUMBLEBEES

Bumblebees like to nest in dry, dark cavities, with a particular favourite being abandoned rodent holes. This is the situation we’ve tried to replicate at the Rec using instructions provided by the Bumblebee Conservation Trust
There are 5 nest sites each comprising an upturned terracotta flowerpot partially sunk into the ground and containing dry moss as nesting material. (Kapok is also good). The moss is slightly raised on wire mesh to prevent it from getting damp. Entrance to the nest is by way of a length of tubing which passes from underneath the pot to emerge above ground a short distance away. These artificial nests aren’t always successful, but we thought we’d give it a go. If you want to try it yourself, remember to position it in a shady location and check out the EcoSapien video for detailed advice
Now is the time to see the large Queen bumblebees on the wing. They’ve recently emerged from winter hibernation and are often observed flying around close to the ground, seeking out possible nest sites. Having found one and provisioned it, she will lay the first eggs that will grow to become female workers. She then hands on the responsibility for foraging, and concentrates on laying further eggs. Later in the season, some of the eggs will develop into male bees and future queens, and once those bees have mated, all the colony will die out, with the exception of the new generation of queen bees. These will set out to find somewhere to hibernate until the following spring when they begin the cycle all over again.

SOLITARY BEES
In contrast, female solitary bees, which look rather like small honeybees, construct tunnels with individual cells. Masonry bee nests can be found, as their name suggests, in gaps in walls and masonry, those of Mining bees in light, well drained soil, and others in hollow plant stems, beetle boreholes, old nail holes, or artificial nests, usually containing bamboo sticks. 
The bee will lay her first egg at the far end of the tunnel, with a supply of bee bread. She will then seal that chamber, and the material she uses will depend on the species. Mason bees and Mining bees use a form of mud, made of earth and saliva,
whereas Leafcutter bees will partition the cells with leaf material. Look out for neatly chewed hemispheres on the edges of your rose leaves; a tell tale sign. The bee will then repeat the process until she reaches the outside edge which she will also seal. The eggs metamorphose into larvae which feed and grow on the bee bread. Most species will then remain in the nest as either pupae or adults until the following spring when they will chew their way out. Amazingly the outer cells develop into male bees so that they emerge first and wait at the entrance to mate with female bees as they appear.
Although each solitary bee has her own nest, they will happily construct them alongside
others, if the conditions are suitable. We’ve installed an insect hotel with potential nest sites for Mason and Leafcutter bees, in the form of tunnels drilled into a block of wood and a supply of bamboo sticks. Our latest venture has been to create habitat for Mining bees. We mixed a substrate of sand, gravel and soil which we’ve put in a buried pot. The idea is that the mixture should be soft enough to create tunnels but not so soft that they collapse. We then made the vertical tunnels from which the bees will hopefully excavate individual side chambers in which to lay their eggs. Unlike the bumblebee nests, these need to be in the sun. Instructions available from People’s Trust for Endangered Species 

We hope you’re able to spot the nests we’ve created at the Rec and might be inspired to try it in your own garden. These wonderful insects need all the help we can give them especially as we’re indebted to them for so much of our food.