Deer flies, also known as horse flies, are aggressive, biting flies that can make spending time outdoors uncomfortable. Getting bitten by a deer fly is not only painful, but their bites can become infected if scratched open. Luckily, there are many strategies you can use to repel deer flies and prevent bites.
What are deer flies?
Deer flies, which belong to the Tabanidae family, are found throughout most of the world. There are over 250 species of deer flies in North America alone. Deer flies range in size from just 5mm to a whopping 25mm long. They are robust flies with large, often colorful eyes. Their bites are painful thanks to scissor-like jaws that tear into skin. Only female deer flies drink blood, which they need to produce eggs. Deer flies are most active in the summer and spring.
Why are deer flies attracted to humans?
Female deer flies locate hosts through senses such as vision, smell, and heat detection. Dark colors, clothing, carbon dioxide from breathing, warmth, movement, and sweat are all cues that attract hungry female deer flies searching for a blood meal. Deer flies tend to be most active mid-morning through mid-afternoon when temperatures are warmest. Shade and woodland edges are areas they congregate.
Preventing Deer Fly Bites
The best protection against deer flies is prevention. Here are some tips to avoid deer fly bites when spending time outdoors:
Avoid peak times and habitats
Deer flies are most active mid-morning through mid-afternoon on warm, sunny days. Avoid shaded woodland edges and wet areas where deer flies congregate from late spring through early fall. If possible, plan outdoor activities for cooler mornings and evenings.
Wear light colors and avoid scents
Deer flies are attracted to dark colors and contrasts. Stick to wearing light-colored clothing like khaki, white, and beige when outside. Avoid wearing perfumes, scented lotions, or hair products as these can also draw in deer flies.
Use a repellent with DEET
Topical repellents that contain 20% or more DEET are effective at deterring deer flies. Apply repellent generously on exposed skin and reapply every few hours as needed. Other repellent options include those with picaridin, IR3535, or oil of lemon eucalyptus.
Repellent Active Ingredient | Effectiveness Against Deer Flies |
---|---|
DEET | Highly effective |
Picaridin | Moderately effective |
IR3535 | Mildly effective |
Oil of lemon eucalyptus | Moderately effective |
Cover up with light fabrics
Wear long sleeves, pants, and socks when possible to protect skin from bites. Lightweight, tightly woven fabrics like cotton are preferable to dark or black clothing. Tuck pants into socks and shirt into pants to close gaps.
Use fans
Deer flies have difficulty flying in wind. Use box fans, ceiling fans, or stand fans outdoors to help repel them. Fans also disperse human odors and carbon dioxide that attract deer flies.
Try herb and essential oil repellents
Certain herbs and natural oils can deter deer flies, including lavender, mint, citronella, eucalyptus, pennyroyal, basil, and lemongrass. Use skin-safe essential oils topically or grow plants around outdoor living spaces.
Treating Deer Fly Bites
Even with preventive measures, deer fly bites may still occur. Here is how to treat the painful bites:
Wash the bite area
Immediately wash the bite with soap and water to clean the wound. This helps prevent infection from bacteria that may have been introduced. Apply an antibiotic ointment as well to support healing.
Use a cold compress
To reduce inflammation, swelling, and itching, apply a cold compress or ice wrapped in a towel to the bite area for 10-15 minutes. The cold helps constrict blood vessels and numb pain receptors.
Take antihistamines
Over-the-counter antihistamines like Benadryl can provide relief from itching. Oral antihistamines also help reduce swelling and skin reactions to the deer fly saliva injected during biting.
Apply hydrocortisone cream
Applying a 1% hydrocortisone cream to the bite can help ease redness, swelling, and itching. Hydrocortisone is a topical steroid that reduces inflammation. However, do not use it for more than a few days.
Monitor for infection
Keep an eye on deer fly bites for any signs of worsening skin redness, swelling, pain, oozing, or streaking redness. See a doctor promptly if a bite appears infected so that antibiotic treatment can be provided if needed.
Deer Fly Bite Home Remedies
In addition to conventional treatments, there are a variety of natural home remedies that may help soothe deer fly bites:
Aloe vera gel
The cooling, anti-inflammatory properties of aloe vera gel can aid healing and reduce itching when applied to the bite. Use pure aloe gel without additives.
Apple cider vinegar
Dabbing apple cider vinegar on the bite provides astringent and antibacterial effects. Dilute with a bit of water if the vinegar stings open bites.
Honey
Apply a dab of medical grade manuka honey to bites. Honey offers antiseptic, wound healing benefits.
Baking soda paste
Make a paste of baking soda and water and apply to the bite to ease itching and swelling. The alkaline baking soda reduces acidity and inflammation.
Oatmeal bath
For itchy skin and numerous bites, an oatmeal colloidal bath can help soothe inflammation. Grind uncooked oats into a fine powder and add to lukewarm bath water.
Onion
Onions have anti-inflammatory compounds that may lessen bite reactions. Apply a thin slice of raw onion to the bite.
Toothpaste
Dab a small amount of regular toothpaste onto the bite. Toothpaste may reduce swelling, itching, and pain. Rinse off completely after 15-20 minutes.
Calamine lotion
The zinc oxide in calamine lotion helps dry out bites and ease itching. Apply a thin layer to affected areas.
Protecting Pets from Deer Flies
Our furry companions are also at risk for annoying and painful deer fly bites when outdoors. Here are some tips for protecting pets:
Use veterinary insect repellents
Topical repellents formulated for dogs and cats containing permethrin, pyrethroids, or other vet-approved ingredients will deter deer flies. Avoid using DEET products on pets. Reapply as directed.
Provide tasty supplements
Feeding pets garlic, brewer’s yeast, vitamin B1, or fish oil supplements may help repel deer flies through skin secretions. Consult your vet first.
Install fans
Use box fans or ceiling fans around pet areas outside to disrupt deer flies. Fans also distribute repellent aromas evenly.
Avoid peak deer fly times
Walk and exercise pets in the early morning or evening when deer flies are less prevalent. Take caution near woods and water where flies congregate.
Keep pets indoors
When deer flies are at their worst, it may be best to simply keep pets indoors as much as possible to prevent bites. Be sure pets have plenty of toys and enrichment indoors.
Spray insecticides
In severe cases, spray pet-safe insecticides formulated with permethrin around pet living spaces about once per week when flies are active. Use caution and follow all label directions.
Preventing Deer Flies in the Landscape
Making landscape and property modifications can help reduce deer fly populations:
Remove breeding sites
Deer flies breed near wet areas like ponds, swamps, and streams. Eliminate standing water or treat with an approved larvicide to disrupt breeding.
Manage livestock areas
Clear manure, rotting hay, and wet bedding from barns, stalls, and fields to eliminate prime deer fly habitat.
Cut or thin vegetation
Deer flies rest in shrubs and woodland edges. Prune, mow, or thin vegetation to remove protective deer fly resting areas.
Install screens
Keep deer flies outside by fixing screens over windows, doors, and porch areas. Use fine mesh for maximum protection.
Use light traps
Specialized light traps with UV bulbs attract and electrocute adult deer flies. Position them 25-50 feet from outdoor living spaces.
Release biocontrols
Natural deer fly predators include dragonflies, predacious mites, and birds. Consider stocking a backyard pond with dragonfly larvae. Leave brush piles to encourage predacious mites.
Deer Fly Control Method | How It Works |
---|---|
Remove breeding sites | Eliminates aquatic habitat where eggs are laid |
Manage livestock areas | Clears prime habitat of manure breeding grounds |
Cut/thin vegetation | Removes protective resting spaces for adults |
Install screens | Physically blocks fly entry into homes/structures |
Use light traps | Attracts and kills adult deer flies |
Release biocontrols | Promotes natural predators that consume deer flies |
Conclusion
Deer flies can quickly turn a relaxing day outdoors into an annoying, painful experience due to their strong bites in search of blood meals. Reduce your risk by wearing light clothing, using repellents, and avoiding peak deer fly hours during warm months. Treat bites with cold compresses, antihistamines, hydrocortisone, and natural remedies like aloe vera for relief. Keeping pets indoors or using pet-safe insecticides and repellents will protect them as well. Removing breeding grounds, managing vegetation, and using light traps and biological controls in the landscape can reduce deer fly populations over time. Stay vigilant against deer flies, but do not let them keep you from enjoying the outdoors.