Red-Tailed Bumblebee

If you see a big jet-black bumblebee with a red tail in Britain, its probably the Red-tailed Bumblebee, Bombus lapidarius. If it has a scruffy white collar, then its a male.

The Red-tailed Bubmblebee has extended its range northwards in recent years and is now common throughout Britain. It can often be seen in parks and gardens. The workers have short tongues and forage on flowers like daisies and thistles which have a big area for them to land on and are made up of small florets, each with a little nectar. Leaving dandelions to grow in the spring helps provide food for these and other insects early on in the growing season.

Let dandelions grow in spring to help insects. Image credit: Pixabay / Claudiu Mladin CC0

The Queens nest under stones and so are sometimes disturbed when these are moved. If you find one like this, have a look without disturbing it then just put the stone back. They may also enter our homes through open windows in search of nesting sites.

The Red-shanked carder bee, Bombus ruderarius, can look similar but is much scarcer in the UK. While the Queens of B. ruderarius are smaller. the workers of the two species can be a similar size. You can tell the difference by looking at the back legs. B ruderarius has red pollen baskets on its otherwise black legs, whereas the leg hairs of B. lapidarius are all black.

Lincoln Kwong was one of the participants at our Summer school in August. He was so inspired by the HOPE collections team at the museum that he decided to start his own insect collection. One of his first specimens was a dead red-tailed bumblebee that he found in his garden. He preserved and pinned this and recorded the data following advice from James.

Bombus lapidarius. Image credit: Lincoln Kwong

Let us know if you have your own collection. You can get in touch using the CONTACT US page. We’d also love to see any pictures any would be happy to feature them in our PHOTO GALLERY!

Featured image credit: Gail Hampshire CC BY 2.0

The Dark Edged Bee-Fly

The Dark edged bee-fly, Bombylius major, is one of the most conspicuous insects to emerge in early spring because of it’s large size and ability to hover in mid air. It is the most common species of Bee-fly in the UK and can be seen in woodland, heathlands, grasslands and gardens from February to June. It has several other common names known as the ‘dark bordered beefly’ or ‘large beefly’. They get these names from their large size and from the dark wavy leading edge of their wings.

Dark edged bee-fly, Bobylius major. Image credit – Flickr / Jean-Marie Hamon, CC BY-SA 3.0

So, is it a bee or a fly? The single pair of wings tells us that this is a fly. A bee would have two pairs of wings. Why would a fly evolve to look like a bee? We think this is to trick predators into thinking it is more dangerous than it is. It certainly works with humans: many people think that the beefly has a large ‘sting’ at the front. In fact, this is just part the fly’s mouth and is quite harmless. The proboscis is adapted to drink the nectar from a wide variety of early-flowering plants. These include primrose, bugle, blackthorn, and cherry blossom. Because they transfer pollen from flower to flower, they are important pollinators in the spring.

Bee-fly feeding on nectar. You can see pollen grains on its legs and body. Image credit – Flickr / Robert Ault, CC BY-SA 2.0

Bee-flies may be harmless to humans but their life cycle is a bit grisly! Females lay their eggs in the underground nests of solitary mining bee nests such as Clarke’s Mining Bee (Andrena clarkella), the Early mining bee (Andrena haemarrohoa), and the Tawny mining bee (Andrena fulva). They collect sand or dust at the end of their abdomens. This sticks to their eggs, making them heavier. It may also help camouflage them. They then flick their eggs into the nest burrows of the bees. Once the eggs hatch, the bee-fly larvae crawl further down the burrows and wait for the bee larvae to grow until they are near full size. The bee-fly larvae then begin to feed on the mining bee larvae, drinking their body fluids and gradually eating them alive. When they have finished feeding, the bee-fly larvae then pupate and overwinter inside the burrow. The next generation of adult bee-flies then emerges from the burrows the following spring.

The Twany mining bee, Andrena fulva. Bee-fly larvae feed on its larvae. Image credit – Flickr / Line Sabroe, CC BY 2.0

You might think that means that bee-flies are bad for other bee species, but this is relationship evolved a long time ago and is part of the complex interaction between living things that exists in all ecosystems. Bee flies do feed on individual mining bees, but there is no evidence that they are harmful to bee populations.

If you spot a bee-fly this spring or summer, you can add your sighting to the national database by completing a simple online form on the Bee-fly Watch website. Why not let us know too? You could even take a picture or draw a picture. Who will spot the first bee-fly of 2021?