The UK’s longest heatwave since the 1970’s is proving prosperous for more than just ice cream vans and paddling pool salesmen. Biting insects are thriving in these warm and often humid temperatures and none more so it seems than horse flies, which can deliver a particularly painful bite.
What is a horse fly?
Horse flies are also known as clags, gladflies or breeze flies and are all part of the family Tabanidae, which suck the blood of mammals. They are most often seen as a problem in rural areas as the females typically bite horses, cattle and other large mammals. Female horse flies slash their victim’s skin in a scissor like motion with specially-designed, knife-like mandibles (mouth-parts), and then lick the blood. They are more than happy to take a blood feed from people as well as livestock.
What do horse flies look like and where do they live?
Horse flies vary from black or dark brown in colour, and can range in size from about 10mm to 25mm long. They can have green or black eyes, with males having contiguous eyes, which differentiate them from females, whose eyes are widely separated. Horse flies make a low-pitched humming noise as they fly, but don’t make as distinctive a noise as mosquitoes, so unfortunately you don’t always hear them coming.
Horse flies are usually found around their main food source livestock, in fields and hedgerows, especially near water, and around stables and farms. However, the current heatwave is sending them further afield in search of wet or marshy areas to breed.
Horse fly season
Female horse flies will lay their eggs in open water, particularly standing water such as ponds, marshes, animal troughs but will also happily use standing water in kid’s paddling pools, ornamental garden ponds or any other source of standing water or damp and boggy areas to breed. Adult horse flies will start to emerge from these marshy, muddy areas where they have been feeding as hatchlings from May through to September.
Horse fly bites
These flies are major carriers of bacteria and pathogens, increasing the risks of infection if you are bitten by them. You’ll not fail to notice a horse fly bite, unlike mosquitoes their main prey of livestock cannot easily escape or brush them away, so horse flies do not need to be subtle about feeding.
Horse fly bites can be very painful. The area of the bite will be a raised, itchy lump – similar to a mosquito bite but with a small open wound (inflicted as the female horsefly cuts the skin with her razor sharp mandibles). The area of the body around the bite may become puffy and swollen, or the bite area may blister.
What can you do if you’re bitten by a horse fly?
Bites from horse flies, although painful should only give discomfort for a few hours, however it may take a while for the wounds to heal. Here’s what you can do to help:
- Clean the wound and surrounding area to help avoid infection.
- Apply a cold compress or ice pack to help alleviate swelling.
- Use Chemist recommended over-the-counter steroid creams containing hydrocortisone or Ibuprofen gels recommended to help reduce swelling and itchiness.
- Try not to scratch the bite (easier said than done, granted) as this can lead to skin infections like Cellulitis (a bacterial infection of the skin and tissues beneath the skin) and the need for antibiotics.
If however the wound starts to produce pus or the swelling is following the line of a vein contact your GP for advice.
How to get rid of horse flies
You can never completely remove the possibility of biting insects taking a nip, but you can take steps to reduce the opportunities they may have to bite you:
Remove standing water – especially in gardens and other areas outside your home. Female horse flies will lay their eggs in open water, so you need to remove opportunities for horse flies to breed:
- Ponds – if you have a garden pond, introduce goldfish as they will eat fly larvae
- Watering cans & buckets – empty these completely once used or cover them to deny flies and mosquitoes access.
- Paddling pools – drain daily or cover securely and clean regularly to deter horseflies from using them as a breeding ground.
- Water butts – cover with well fitted lids to deny access for breeding.
- Vegetation & tall grass – keep your grass and vegetation trimmed on a regular basis, especially along ditches as horse flies can find moist and cool breeding areas in tall grasses and can retreat to these areas during the hottest times of the day.