Small, black bees dominate the solitary bee world again this month, but they are joined by a medium-sized furry, striped plasterer bee and a parasitic blood bee with a red abdomen. You may also notice that some of the bumblebees just got a lot larger again, like the size they were in the spring. That’s because a new generations of queen bumblebees are flying. Many will have mated with males from nearby nests and are looking for somewhere safe to hunker down for the next few months until next spring when they will create their own colony.
Tips for IDing August bumblebees:
- Male white-tailed bumblebees (Bombus lucorum) are commonly seen in parks and gardens at this time of year resting on flowers before flying in search of a virgin bumblebee queen to mate with. You can tell the males apart from workers and queens because they have bright yellow hairs on their face. The males of all bumblebee species are smaller than the queens, but bigger than the workers.
- Buff-tailed bumblebees (Bombus terrestris) are the most common bumblebee in the UK. In August, the huge queens are easy to spot as they drink nectar from flowering plants to build up their energy and strength for the winter ahead. They will either be mated and looking for a safe, small hole in the ground to sleep until spring, or in Southern England they are more likely to have mated and be looking for an underground nest now in order to rear a new colony of workers that will live through our mild winter, feeding on Mahonia and Hellebores.
- Common carder bees (Bombus pascurorum) are one of my favourite bees because they are frequent visitors to the garden until October and are small and cute with their brown/gingery coat, but they are often overlooked for more showy, striped bumblebees. As their English name suggests, they are widespread, and they tease out (‘carder’) pieces of moss and grass for nesting material. Unlike many bumblebee species, they nest on the ground, rather than below it, often under hedges, or garden sheds, or in tall open grassland.
You may also see red-tailed bumblebees, tree bumblebees and garden bumblebee this month. All the castes could be out – the large queens, and smaller workers and males. And a new generation of cuckoo bumblebees may also be flying, such as the Field cuckoo bee (Bombus campestris), which lays its eggs in carder bees’ nests. Here’s a full guide to cuckoos. ID tip: They have darker wings than nest-making bumblebees and no pollen baskets because their host’s worker bees collect the pollen to feed the cuckoo bees’ females and males.
How to ID August solitary bees:
- Willughby’s leafcutter (Megachile willughbiella), the most common of the leafcutter bees, is still flying until the end of the month. They get their name, like many solitary bees, from how they construct their nests. If, like me, you’ve not yet seen a female flying home with a piece of leaf she’s cut from a rose or lilac bush clasped between her legs, then watch this fantastic footage from Devon-based field naturalist, John Walter. She lines her nest and plugs it with pieces of leaf. She can nest in a bee hotel, alongside red mason bees, but can also be found in in many other artificial cavities including gaps in window frames, holes in walls and even rubber hoses and folded garden parasols. Tip: A similar in size to a honeybee, leafcutters are brownish grey and collect pollen on the underside of their tummy, which they have a habit of lifting up in the air while feeding on flowers.
- Davies’ plasterer bee (Colletes daviesanus) – is a smallish 5-7mm bee with a furry thorax and a shiny abdomen with grey-white stripes. There are 500 known species of plasterers – also called Colletes bees – worldwide, but only nine in Britain. This is the main one you’ll see in your garden on any daisy-like flower and nesting in weathered sandstone walls, soft mortar or in south-facing slopes of bare soil. They are called plasterer bees because they plaster the cells of the nests with a cellophane-like resin substance they produce which is both waterproof and fungus-resistant.
- Common yellow-faced bees (Hylaeus communis) are one of many small, (5mm) predominately black bees which frequents gardens from mid to late summer. This one has tiny yellow spots or a triangle on its face, and yellow on its legs. It nests in a variety of small cavities including hollow stems and manmade bee hotels if the dimensions of the tube are small enough. It too lines the cells of its nest with waterproof, anti-fungal resin applied with its tongue, which explains why yellow-faced bees are classified in the same family as Colletes. You won’t see pollen on their hind legs or under their tummy, because, unusually for a bee, they carry pollen back to its nest in a special stomach, called a crop and regurgitate it to make a semi-liquid mixed with nectar to feed their brood (larvae).
- Small scissor bees (Chelostoma campanularum) were easy to spot last month despite their diminutive size, because the 4.5mm-long males shelter in the middle of bellflowers (campanula in Latin) during dull weather and/or at night. Now the bellflowers have gone, look in hardy geraniums instead. Another cavity nester, they use pre-existing holes in dead wood including fence posts and plug the holes with small particles like sand grains and pebbles.
- Common furrow bees (Lasioglossum calceatum) – are another black bee that fails to conforms to most people’s image of a bee. It has a smooth elongated body, often with a metallic green or blue sheen. If you’ve not seen them yet, try looking in thistles, knapweeds and ragworts early in the morning as the males may be roosting there overnight. They excavate underground burrows in light soil in which to nest. Like many solitary bees, they like living next door to each other in large aggregations.
- Blood bees (Sphecodes) can often be found where furrow bees are nestingas they invade their nests and those of mining bees. There are several hundred species of these parasitic bees globally and around 17 in the British Isles. They range in size from 4mm to 8mm, but can be identified from other black, hairless bees by their red abdomen which looks as if it is full of blood. Telling one blood bee species from another can be very challenging, despite possessing some of the best descriptive common names such as swollen-thighed, bare-saddled and dull-headed. If you see one on heathland or coastal dunes, chances are it could be the Sandpit blood bee. They are actually cleptoparasites, which means the female enters a host’s nest, opens up a cell and destroys the egg, or larvae, in it and replaces it with her own egg before resealing it. Females are usually found around the nests of the host, while males are often hanging out on a variety of daisy-like flowers and umbellifers. Tip: Don’t kill these bees to save the furrow and mining bees. Nature works in mysterious ways and we must respect that.
How to help bees in August:
- Plant different flowers for different bees. Hollyhocks, sunflowers, globe thistles are cardoons are all magnets at this time of year for short-tongued bees, along with open-faced dahlias. For the long-tongued bumblebees, black horehound, salvias and buddleia are still flowering, and hemp agrimony is good if you have damp growing conditions. Geranium rozanne and Calamint are still going strong, and Common sneezeweed (Helenium autumnale) is starting to produce coppery blooms which are a top attraction for solitary bees according to Rosybee nursery’s fantastically helpful research . Marjoram (Origanum), Anise hyssop, thyme and Bergamot, are all later-flowering herbs that do well in pots in a sunny position.
- If you only have a window box, Mexican fleabane (Erigeron karvinskianus), creeping thyme (Thymus serpyllum) and trailing nasturtium and bird’s-foot trefoil are still flowering. Add sedum for late flowers and annuals such as cosmos and snap dragons.
- If you let your lawn grow into a wildflower meadow this year, now is a good time to do what’s called the ‘haycut’. Cut to 4cm with a mower, or better still use a scythe or shears. Leave the cuttings for a few days to let seeds drop to the surface of the soil, then rake the cuttings up to reduce soil fertility and encourage more wildflowers next year.
- Gather seeds from plants such as poppies, love-in-a-mist, bellflowers and foxgloves. Store them in labelled paper bags in a cool, dry place for sowing or scattering next spring. Or, just scatter them around your garden now and hope for the best.
- Leave parts of the garden undisturbed, as ground nesting bumblebee queens may be looking for a snug place to spend the winter.
- Ditch the weed killers and pesticides.
- You can put up bee hotels now, but you probably won’t get any visitors until next spring. You can make a bee hotel. We recommend buying ones that you can clean out in the winter and store the bee cocoons safely in a cold, dry, dark place. We have successfully installed these bee hotels under the south-facing eaves of our garden shed. If you want to see what is happening inside a bee hotel, you could invest in an observation box with a Perspex viewing window such as this award-winning one from Nurturing Nature.
- It’s still not too late to drill holes in blocks of wood – 10mm, 8mm, 6mm and 4mm diameters and up to 30 cm deep (although some bees only need a depth of a few centimetres to nest in) – and screw them to a sturdy support. Drill holes in existing structures such as fence posts, or dead trees. Small scissor bees or yellow-faced bees may take up residence.
- Create a bank of sand mixed with some clay soil against a south facing wall for mining bees which like to burrow into sand. Create steps in the sand as some bees like to nest vertically and others horizontally. The clay will help the bank to keeps its shape after the bees have tunnelled into it.
- Provide a source of water for thirsty bees. This can be a shallow bowl or saucer with stones or pebbles in that the bees can stand on while they are drinking. Bees can’t swim!
For information on IDing and helping bees earlier in the year see my Bees to See in July blog here, Bees to See in June blog here, Bees to See in May blog here and Bees to See in April blog here, Bees to See in March blog here.