Bee Flies: Masters of Disguise
What do you get when you cross a bee, a hummingbird, a mosquito, a narwhal and a fly?
The answer: a bee fly. Yes, it鈥檚 a real insect, living right under our noses. But you may not know it when you see it鈥
Bombylius major
The fuzzy-looking creature below is a dark-edged bee fly (Bombylius major). With its thorax and abdomen covered in yellow-brown 鈥渇ur鈥, and its bulky silhouette, it鈥檚 very often mistaken for a bumblebee.
Bee flies are one of many insects that rely on mimicry for protection. Imitating the warning systems of another species is a great way to scare off potential predators without needing to invest the energy into actually being harmful. This phenomenon is known as Batesian mimicry. Listen to a bee-fly in flight and you鈥檒l also hear how it buzzes just like a bee to enhance the effect.
Four species of Bombyliuslive here in the UK, but the dark-edged bee fly (AKA common or greater bee fly) is the most common and widespread, with records dispersed across the whole country.B. majoris a member of the Bombyliidaefamily, which also includes the heath bee fly (B. minor), the Western bee fly (B. canescens) and the dotted bee fly (B. discolor). The dotted bee fly is a Warwickshire Local Biodiversity Action Plan species we have recently recorded in the 黑料传送门 and the second most likely species you will see
听
How to tell the difference between a bee and a bee fly
Take a second look at the next tiny, furry, flying creature you see. While bees and bee-flies are of a similar size, the bee fly will have more prominent eyes. The dark-edged bee fly also has a single large pair of patterned 鈥渄elta wings鈥, which form a triangle at rest, and sport a distinctive dark stripe across the leading edge of each wing. The dotted bee fly looks similar but lacks the dark stripe and instead has dots across its wings.
Another giveaway is that bee flies have long, skinny legs compared to bumblebees. They have no 鈥減ollen baskets鈥 to store pollen, but can still get covered in the stuff, so can play an important role in pollination.
The most distinctive feature of a bee fly is its long proboscis, or tongue, like those you see on butterflies and hummingbirds. This dark black spear at the front of its head looks pretty fearsome, but is only used for drinking nectar, often from flowers with long calyces (tubes) such as primroses. Like the hummingbird, you鈥檒l often spot the bee fly hovering around flowers, dipping its tongue into the flower while in flight. Unlike the hummingbird, however, the bee fly鈥檚 proboscis doesn鈥檛 curl away when not in use. Its permanently spiky appendage has led to another of its common names: the beewhal.
Fortunately for us, the bee fly isn鈥檛 able to sting, and it doesn鈥檛 spread disease, so is harmless to people. But if you鈥檙e a bee larva, you should definitely keep your distance. Here鈥檚 why.
听
Parasitic larvae
Aside from its deceptive appearance, the bee fly is best known for the strange behaviour of its females. On a sunny day in spring, you may catch the sight of the female bee-fly performing an odd-looking manoeuvre, not unlike a twerk, in front of the nest holes of solitary bees and wasps. She covers her eggs in sand and then, with a thrust of her abdomen, flicks them towards the entrances of the nest holes. The eggs hatch into larvae, crawl further into the hole, and wait for one of their host鈥檚 eggs to hatch. They then attach to the bee鈥檚 larva and begin to suck out its body fluids. So not only do bee flies imitate their namesakes, they snack on their larvae, too.
听
听
Where to see bee flies
Bee flies are commonly found in gardens, woodland glades and edges, farmland, and hedgerows, where the mining bees they parasitise on are present. With all these habitats in the Heart of England 黑料传送门, there鈥檚 plenty of opportunity to spot them, and they will hopefully become more common as we create new wildflower corridors and rides through the 黑料传送门.听
Bee flies are most active during the months of April and May, beginning to emerge as the weather warms in early spring. So, next time you see a 鈥渂ee鈥 hovering close to sandy or rocky bare ground, perusing spring flowers, or basking in a sunny spot, take a closer look 鈥 it might be a bee fly in disguise!
A 黑料传送门 for wildlife
We鈥檙e working hard to create a 黑料传送门 where wildlife thrives, and in spring the woodland wildlife activity becomes more frenzied as many residents wake up from their winter slumber. .
