Nature Notes May 2024

If you have a bee hotel in your garden, now is the time of year when it starts to become interesting. Any bees that have been resident over winter will now be fully grown and ready to start flying as soon as they have fought their way out through the plug at the mouth of their nest hole. These plugs may be made of mud or of folded segments of leaves, depending on the species of bee, and they are intended to keep out predators and parasites. The first photo shows the nest holes of Leafcutter Bees. In my garden they cut out segments of leaves from rose plants which they roll up and stuff into the entrance to the nest hole.

One of the commonest bees emerging from the hotels at this time of year is the Red Mason Bee. The males emerge first and can often be seen swarming around the hotel awaiting the emergence of the females. When a female emerges she is usually grasped by a much smaller male with minimal courtship, although there may be some stroking of the antennae. After mating, the females will create a nest which in the case of the bee hotel just involves clearing out one of the available tubes. A cell at the end of the tube is then filled with nectar and pollen and a single egg laid in the cell. Fertilised eggs become female bees, whereas unfertilised eggs become males. A small amount of wet mud is collected and used to form a cell wall which encloses the first cell. The process is then repeated until the nest hole is full. Before the advent of bee hotels, this species used a variety of holes, including in the soft mortar of walls, cracks around window frames, thatched roofs, beetle holes and empty shells.

There are lots of commercially available bee hotels and I’m sure that most of them will attract bees, although it may take some time before they appear in any numbers. The only requirements are a collection of suitable holes and a roof to keep the worst of the rain at bay. Most include a number of sections of bamboo cane and blocks of wood with holes of various diameters drilled in them. You may find that those with the shiniest finish are not necessarily the most popular with the bees initially – it maybe the smell of paint or varnish that is putting the bees off.

With even limited handyman abilities, you may get the urge to build a bee hotel to your own design and there are plenty of plans on the internet to help you get started. This is also a good way to get youngsters involved in conservation, giving them a chance to look at several stages of the life cycles of solitary bees. Any box of the appropriate size, filled with a selection of canes and pieces of wood with holes drilled can be put up in a sunny location on a wall or securely attached to a tree branch will serve. Always put it up somewhere it will get lots of sun as cold bee nests often fail. We have one species of Honey bee in this country, around 8 common species of Bumblebees, but we have several thousand species of solitary bees. Keeping watch on your own bee hotel gives you the opportunity to get close to a few of these attractive (and totally harmless) insects.