Deer flies (Chrysops spp.) are smaller relatives of horse flies, distinguished by their patterned wings with dark bands or spots and their brilliantly colored, patterned compound eyes. Like horse flies, only females bite — they use the same slashing mouthparts to create a blood pool. Deer flies are particularly persistent and aggressive, often circling the head and targeting the neck, scalp, and ears. They are attracted to movement, dark colors, carbon dioxide, and body heat. Larvae develop in wet soil and shallow water margins, making deer flies most abundant near rivers, streams, ponds, and irrigated agricultural areas in Arizona. Their bite is sharp and painful and can cause significant allergic reactions in sensitive individuals. Deer flies are also capable of transmitting tularemia (rabbit fever) in some regions, though this is rare in Arizona.
👁Warning Signs
Small flies with patterned wings circling the head persistently. Sharp, painful bites on the head, neck, and ears. Presence near water sources and riparian areas.
⚠Health & Property Risks
Painful bites with potential for allergic reactions. Rare potential for tularemia transmission. Significant nuisance near water sources.
Prevention Tips
Use DEET-based repellents on exposed skin. Wear light-colored clothing and hats. Avoid peak activity times near water (warm, sunny hours). Sticky traps (Olson Sticky Deer Fly Traps) worn on hats can be effective.
🛡Professional Treatment
Individual repellent use is the primary defense. No practical area-wide control. Sticky traps for personal protection.
Frequently Asked Questions — Deer Fly
The Deer Fly (Chrysops spp.) is yellow-brown to black with patterned wings; iridescent patterned eyes and typically measures ¼–½ inch. Deer flies (Chrysops spp.) are smaller relatives of horse flies, distinguished by their patterned wings with dark bands or spots and their brilliantly colored, patterned compound eyes. Like horse flie.
The Deer Fly poses a moderate risk. Painful bites with potential for allergic reactions. Rare potential for tularemia transmission. Significant nuisance near water sources.
In Arizona, deer flys are most often encountered in the following situations: Small flies with patterned wings circling the head persistently. Sharp, painful bites on the head, neck, and ears. Presence near water sources and riparian areas.
The Deer Fly is most active during: Late spring through summer near water sources. Arizona's warm desert climate can extend activity periods compared to other states, so year-round vigilance is recommended in the Phoenix metro and surrounding areas.
Use DEET-based repellents on exposed skin. Wear light-colored clothing and hats. Avoid peak activity times near water (warm, sunny hours). Sticky traps (Olson Sticky Deer Fly Traps) worn on hats can be effective.
Individual repellent use is the primary defense. No practical area-wide control. Sticky traps for personal protection.
Most fly species are drawn to food sources, moisture, organic waste, and breeding sites. For Deer Flys specifically: Small flies with patterned wings circling the head persistently. Sharp, painful bites on the head, neck, and ears. Presence near water sources and riparian areas.. Eliminating attractants is the first step — Pest Control Bros can identify the source and recommend targeted control.
Dealing with Deer Fly?
Pest Control Bros LLC serves Maricopa, Chandler, Casa Grande, Tempe, Gilbert, and Mesa. No contracts. Free inspections. Same-week service.
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