Biting Flies in Alabama: How to Identify and Avoid Each Type

Alabama’s warm, humid climate creates perfect breeding conditions for aggressive biting flies that can turn outdoor activities into painful ordeals.

With the state experiencing increased rainfall and extended warm seasons, fly populations have surged, making Alabama home to some of the most persistent biting species in the Southeast.

Whether you’re hiking in the Appalachian foothills, fishing along the Gulf Coast, or simply enjoying your backyard, knowing how to identify and avoid these six problematic species can save you from painful bites and potential disease transmission.

Understanding these flies isn’t just about comfort—it’s about safety. Each species has distinct behaviors, preferred habitats, and peak activity times that determine your risk level and the most effective protection strategies.

Stable Flies

Stable flies earn their reputation as one of Alabama’s most aggressive biters, delivering painful stings that feel like needle pricks.

These gray flies measure about ¼ inch long and feature a prominent, forward-pointing proboscis that distinguishes them from common house flies.

Key Insight: Stable flies are the only common fly species that both males and females bite, making encounters twice as likely during peak activity periods.

You’ll recognize stable flies by their distinctive resting position—they perch with their wings spread at a 45-degree angle from their body.

Their gray coloration includes four dark stripes running lengthwise down their thorax, and their legs appear noticeably longer than those of house flies.

These flies thrive around decaying organic matter, particularly horse barns and livestock facilities. In Alabama’s agricultural regions, they breed in wet hay, manure piles, and compost heaps. Urban populations often develop around poorly maintained garbage areas and pet waste.

Peak Activity Times:

• Early morning hours (6-10 AM)
• Late afternoon (4-7 PM)
• Warm, humid days with temperatures between 70-85°F

Protection Strategies:

• Apply permethrin-treated clothing when working around livestock or compost areas
• Remove decaying organic matter within 50 feet of outdoor gathering spaces
• Use fans on patios and porches—stable flies are weak fliers and avoid windy conditions
• Wear long pants and closed shoes during peak activity hours

Common Mistake: Many people mistake stable flies for regular house flies and don’t take protective measures until after being bitten repeatedly.

Black Flies

Black flies, also known as buffalo gnats, pose a serious threat to anyone enjoying Alabama’s waterways and wooded areas.

These small, dark flies rarely exceed 1/8 inch in length but deliver disproportionately painful bites that can cause severe allergic reactions in sensitive individuals.

The most distinctive feature of black flies is their humpbacked appearance, which gives them their “buffalo gnat” nickname.

Their bodies appear almost black with a metallic sheen, and they have broad, clear wings that fold over their backs when at rest.

Breeding and Habitat Preferences:

Black flies require flowing water for reproduction, making them particularly problematic near Alabama’s numerous streams, rivers, and creeks.

They prefer clean, fast-moving water where females lay eggs on rocks, vegetation, or debris just below the water surface.

Pro Tip: Black flies are most active during daylight hours and rarely bite after sunset, unlike mosquitoes. Plan water activities for late evening to avoid peak biting times.

Black fly bites typically appear as small, red welts that itch intensely and may take weeks to heal. Some individuals experience severe swelling, particularly around the eyes and ears where black flies prefer to feed.

Effective Avoidance Measures:

1. Wear light-colored, tightly woven clothing with long sleeves and pants
2. Apply DEET-based repellents to exposed skin and clothing
3. Use head nets when fishing or hiking near waterways during peak season
4. Avoid outdoor activities near flowing water during morning hours (8 AM-11 AM)
5. Choose campsites and picnic areas at least 100 yards from streams when possible

The key to black fly protection lies in understanding their behavior—they swarm around the head and neck area and are particularly attracted to carbon dioxide and body heat.

Sand Flies

Despite their name, Alabama’s sand flies aren’t limited to sandy beaches—they thrive in various moist environments throughout the state.

These tiny flies, measuring only 1/16 to 1/8 inch long, are among the smallest biting flies you’ll encounter, but their bites pack a surprising punch.

Sand flies have a distinctive mothlike appearance with hairy wings held roof-like over their bodies when at rest. Their bodies range from pale yellow to light brown, and they move in characteristic hopping motions rather than direct flight patterns.

Habitat and Breeding Sites:

Sand flies prefer humid environments with organic debris for larval development. In Alabama, they commonly breed in:

• Leaf litter and mulched garden areas
• Damp soil around air conditioning units
• Crawl spaces and basement areas
• Compost piles and organic waste
• Tree holes and rock crevices

Important Note: Sand flies are weak fliers and rarely travel more than a few hundred yards from breeding sites. Identifying and eliminating nearby breeding sources is often the most effective control method.

These flies are most active during dawn and dusk hours, particularly on calm evenings when wind speeds drop below 5 mph. They’re attracted to artificial lights and will often gather around porch lights and windows during evening hours.

Sand Fly Bite Characteristics:

• Small, red bumps that develop into itchy welts
• Often occur in clusters on exposed skin
• May cause allergic reactions in sensitive individuals
• Healing time ranges from 3-10 days depending on individual response

Prevention and Control Methods:

1. Environmental Management:
   • Remove organic debris within 20 feet of living areas
   • Improve drainage around foundations and air conditioning units
   • Keep mulch layers thin (less than 2 inches) and away from building foundations
   • Seal cracks and crevices in exterior walls where flies might rest
2. Personal Protection:
   • Use fine-mesh screens (18×16 mesh or smaller) on windows and doors
   • Apply repellents containing picaridin or DEET before outdoor evening activities
   • Wear long sleeves and pants during peak activity periods
   • Position outdoor lighting away from gathering areas to reduce attraction

Sand flies pose particular challenges for homeowners because they can breed in small amounts of organic matter that might go unnoticed. Regular property maintenance and moisture control are essential for long-term management.

Deer Flies

Deer flies rank among Alabama’s most persistent and aggressive biting flies, with a tracking ability that makes them nearly impossible to outrun.

These medium-sized flies, measuring ¼ to ½ inch long, are easily recognizable by their large, iridescent eyes and distinctive wing patterns featuring dark bands or spots.

Their flight behavior sets them apart from other biting flies—deer flies circle around your head in a distinctive pattern, often making a distinctive buzzing sound before landing to bite.

They’re visual hunters, attracted to movement, dark objects, and carbon dioxide, which explains why they persistently follow moving targets.

Physical Identification Features:

Habitat and Seasonal Patterns:

Deer flies thrive in Alabama’s diverse ecosystems, particularly areas that combine water sources with vegetation. They’re most commonly encountered in:

• Wooded areas near ponds, streams, or wetlands
• Golf courses with water hazards and tree lines
• Parks and recreational areas with mixed habitats
• Rural properties with livestock and water sources

Peak deer fly season in Alabama runs from late May through August, with the highest populations typically occurring in June and July. They’re most active during warm, sunny days with minimal wind, particularly between 10 AM and 4 PM.

Pro Tip: Deer flies are strongly attracted to moving vehicles and will often follow cars, ATVs, or boats, making them a particular nuisance for outdoor recreation enthusiasts.

Behavioral Patterns and Attack Strategies:

Understanding deer fly behavior is crucial for effective avoidance. These flies exhibit several predictable patterns:

• They prefer to bite on the head, neck, and shoulders
• Males don’t bite—only females seeking blood meals for egg production
• They’re persistent hunters and will follow targets for considerable distances
• Hot, humid days trigger peak activity levels

Effective Deterrent Methods:

1. Motion-Based Deterrents:
   • Wear wide-brimmed hats with attached mesh netting
   • Use moving objects like fabric strips tied to hats or equipment
   • Install fans in outdoor seating areas (deer flies avoid windy conditions)
2. Chemical Protection:
   • Apply DEET or picaridin repellents to clothing and exposed skin
   • Treat clothing with permethrin for long-lasting protection
   • Use sticky traps designed specifically for deer flies
3. Timing and Location Strategies:
   • Plan outdoor activities for early morning or late evening hours
   • Choose open areas away from tree lines and water sources when possible
   • Avoid wearing dark clothing, which attracts deer flies more readily

Common Mistake: Many people try to swat at circling deer flies, which only increases their agitation and persistence. Instead, move to a windy area or seek shelter until the flies lose interest.

Deer fly bites are typically more painful than other fly bites and may cause significant swelling and itching that persists for several days. Some individuals develop allergic reactions that require medical attention.

Biting Midges (No-See-Ums)

Biting midges, commonly called no-see-ums or sand gnats, are Alabama’s most challenging biting flies due to their microscopic size and ability to penetrate standard window screens and clothing.

Measuring only 1-3 millimeters long, these tiny flies are nearly invisible to the naked eye but deliver bites that feel completely disproportionate to their size.

These flies appear as tiny gray or black specks and are most easily spotted when they land on light-colored surfaces.

Their wings have a distinctive mottled pattern when viewed under magnification, and they hold their wings folded over their bodies when at rest.

Why No-See-Ums Are So Problematic:

The combination of their microscopic size and aggressive biting behavior makes no-see-ums particularly difficult to manage. They can:

• Pass through standard 16×16 mesh window screens
• Penetrate loosely woven fabrics
• Bite through thin clothing materials
• Remain active in light wind conditions that deter larger flies

Breeding and Habitat Requirements:

No-see-ums require moist or saturated soil for reproduction, which makes Alabama’s humid climate ideal for their development. Common breeding sites include:

• Marshy areas and wetlands
• Irrigated lawns and garden beds
• Areas around leaking outdoor faucets or air conditioning units
• Mud flats and pond edges
• Potted plants with consistently moist soil

Peak Activity Periods:

• Dawn and dusk hours (most active)
• Overcast days with high humidity
• Calm evenings with minimal wind
• Areas near outdoor lighting after dark

Bite Characteristics and Health Concerns:

No-see-um bites typically appear as small, red welts that develop into intensely itchy bumps. The bites often:

• Occur in clusters on exposed skin
• Develop into fluid-filled blisters in sensitive individuals
• Cause itching that persists for 1-2 weeks
• May lead to secondary infections from scratching

Important Note: Some people develop severe allergic reactions to no-see-um bites, including widespread swelling, difficulty breathing, or systemic reactions requiring immediate medical attention.

Comprehensive Protection Strategies:

1. Physical Barriers:
   • Install fine-mesh screens (20×20 mesh minimum) on windows and doors
   • Use tightly woven clothing with long sleeves and pants
   • Apply permethrin treatment to outdoor clothing and gear
   • Wear closed shoes and socks during peak activity times
2. Environmental Controls:
   • Eliminate standing water and over-watered areas near living spaces
   • Improve drainage around foundations and outdoor gathering areas
   • Use fans in outdoor seating areas (no-see-ums cannot fly in winds above 3-5 mph)
   • Position outdoor lighting away from seating and activity areas
3. Chemical Protection:
   • Use repellents containing DEET, picaridin, or permethrin
   • Apply repellent to both skin and clothing for maximum effectiveness
   • Consider professional pest control for severe infestations
   • Use area repellent devices for outdoor gatherings

Pro Tip: No-see-ums are most active during the first and last two hours of daylight. Planning indoor activities during these times can significantly reduce exposure.

Horse Flies

Horse flies represent the largest and most intimidating of Alabama’s biting flies, with some species reaching over an inch in length.

These robust flies deliver the most painful bites of any fly species, often causing immediate bleeding and long-lasting welts that can persist for days.

You can identify horse flies by their large size, prominent compound eyes, and powerful build. Their eyes are particularly striking—large, often brilliantly colored in shades of green, gold, or brown, and positioned prominently on their broad heads. Their bodies are typically dark brown to black with yellowish markings.

Size and Species Variations:

Habitat and Behavioral Patterns:

Horse flies require aquatic environments for reproduction, with females laying eggs on vegetation overhanging water sources. In Alabama, they’re most commonly found near:

• Farm ponds and livestock watering areas
• Slow-moving streams and river backwaters
• Wetlands and marshy areas
• Lake shores and recreational water bodies

These flies are visual hunters with exceptional eyesight, capable of spotting potential hosts from considerable distances. They’re particularly attracted to:

• Large, moving objects (livestock, vehicles, people)
• Dark-colored clothing and objects
• Shiny or reflective surfaces
• Carbon dioxide and body heat emissions

Peak Activity and Seasonal Patterns:

Horse flies are most active during Alabama’s hottest months (June through September), with peak populations typically occurring in July and August. They prefer:

• Hot, sunny days with temperatures above 80°F
• Calm conditions with minimal wind
• Midday hours when temperatures peak (10 AM to 4 PM)
• Areas with mixed sun and shade near water sources

Why Horse Fly Bites Are So Severe:

Unlike other biting flies that pierce the skin cleanly, horse flies use scissor-like mandibles to cut through skin, creating larger wounds that bleed more freely. This feeding method:

• Causes immediate, sharp pain similar to a bee sting
• Creates wounds that may continue bleeding for several minutes
• Increases risk of secondary bacterial infections
• Can cause severe allergic reactions in sensitive individuals

Comprehensive Avoidance Strategies:

1. Location and Timing:
   • Avoid areas near water sources during peak activity hours
   • Choose windy locations for outdoor activities (horse flies are strong fliers but avoid gusty conditions)
   • Plan water-based recreation for early morning or evening hours
   • Stay away from livestock areas during hot, sunny periods
2. Personal Protection:
   • Wear light-colored, tightly woven clothing with long sleeves and pants
   • Apply DEET-based repellents to both skin and clothing
   • Use permethrin-treated clothing for extended outdoor exposure
   • Consider head nets and protective clothing for high-risk activities
3. Movement and Behavior:
   • Avoid rapid movements that attract visual hunters
   • Don’t wear shiny jewelry or accessories
   • Move to shaded, breezy areas when horse flies are present
   • Cover or avoid dark-colored vehicles and equipment that attract flies

Common Mistake: Attempting to swat horse flies often results in more aggressive behavior. Instead, move to a different location or seek shelter until they lose interest.

First Aid for Horse Fly Bites:

• Clean wounds immediately with soap and water
• Apply cold compresses to reduce swelling and pain
• Monitor for signs of infection (increased redness, warmth, pus)
• Seek medical attention for severe allergic reactions or signs of infection

Protecting Yourself from All Alabama Biting Flies

Successfully avoiding Alabama’s diverse biting fly population requires a comprehensive approach that addresses the unique behaviors and preferences of each species.

Rather than relying on single protection methods, the most effective strategy combines multiple deterrent techniques tailored to your specific outdoor activities and locations.

Universal Protection Principles:

The most successful fly protection strategies focus on three key areas: timing your outdoor activities, creating physical barriers, and using chemical deterrents appropriately.

Understanding when and where different species are most active allows you to plan activities during lower-risk periods and choose locations that naturally reduce fly encounters.

Timing-Based Avoidance:

• Schedule outdoor activities during windy periods (most biting flies avoid winds above 10 mph)
• Plan water-based recreation for late evening hours when most species become less active
• Avoid peak activity periods: early morning (6-10 AM) and late afternoon (4-7 PM) for most species
• Choose overcast days over sunny days for outdoor work near water sources or livestock areas

Comprehensive Clothing Strategies:

Your clothing choices can dramatically reduce bite risk across all fly species. Effective protective clothing includes:

• Light-colored, tightly woven fabrics that flies cannot penetrate
• Long sleeves and full-length pants during peak fly season (May through September)
• Closed shoes and socks to protect feet and ankles
• Wide-brimmed hats with attached netting for head and neck protection

Pro Tip: Permethrin-treated clothing provides long-lasting protection against all biting fly species and remains effective through multiple washings.

Multi-Species Repellent Application:

Different fly species respond differently to various repellent compounds, making combination approaches most effective:

Environmental Modifications:

Creating less attractive environments around your property reduces fly populations and bite risk:

1. Water Management:
   • Eliminate standing water in containers, clogged gutters, and low-lying areas
   • Ensure proper drainage around foundations and outdoor gathering spaces
   • Maintain swimming pools and water features to prevent stagnant conditions
   • Remove organic debris from around water sources
2. Vegetation and Habitat Control:
   • Keep grass and vegetation trimmed near outdoor living areas
   • Remove leaf litter and organic debris that provides breeding sites
   • Position outdoor seating areas away from tree lines and water sources
   • Use fans in outdoor gathering spaces to create airflow

Activity-Specific Protection Plans:

Different outdoor activities require tailored protection approaches:

Hiking and Camping:

• Choose campsites at least 100 yards from water sources when possible
• Set up in breezy areas with minimal vegetation
• Use permethrin-treated gear and clothing
• Pack head nets and long-sleeved clothing regardless of weather forecasts

Fishing and Water Sports:

• Plan activities for early morning (before 8 AM) or evening hours (after 6 PM)
• Wear light-colored, protective clothing with repellent application
• Use portable fans on boats and fishing platforms
• Avoid areas with visible fly swarms or high insect activity

Gardening and Yard Work:

• Schedule outdoor work during windy periods or cooler parts of the day
• Wear protective clothing even for short tasks
• Remove breeding sites like compost piles and standing water regularly
• Consider professional treatment for severe property infestations

Important Note: If you experience severe allergic reactions to fly bites, including widespread swelling, difficulty breathing, or systemic reactions, seek immediate medical attention and consider carrying emergency medications as prescribed by your healthcare provider.

Emergency Bite Treatment:

When prevention fails, prompt treatment reduces discomfort and complications:

• Clean bite areas immediately with soap and water
• Apply cold compresses to reduce swelling and itching
• Use antihistamines for allergic reactions and persistent itching
• Avoid scratching to prevent secondary infections
• Monitor bites for signs of infection requiring medical attention

By implementing these comprehensive protection strategies and understanding the specific behaviors of Alabama’s six most problematic biting fly species, you can significantly reduce your risk of painful encounters and enjoy the state’s abundant outdoor recreation opportunities with greater comfort and safety.