How to Tell the Difference Between Biting Flies and Filth Flies (and Choose the Right Trap)

When flies invade your space, they can be more than just a nuisance—they can bite, spread disease, and spoil your time outdoors. But not all flies are the same. Biting flies and filth flies behave differently and are attracted to different things. Identifying which type of fly you’re dealing with is crucial to picking the right trap.

What Are Filth Flies?

Filth flies are scavengers that breed and feed on decaying organic matter and animal feces, making them a health hazard as well as a nuisance. These include house flies, blow flies, and garbage flies. Here's how you can tell if you're dealing with filth flies:

Appearance

Filth flies are generally smaller than biting flies. The common house fly, for example, is about 1/4 inch long, with gray bodies and distinctive red eyes. Blow flies have a metallic green or blue appearance, while garbage flies are dull in color.

Behavior

Unlike biting flies, filth flies don’t target humans or animals for blood. They are more interested in rotting food, manure, and garbage. You’ll notice them buzzing around trash cans, compost bins, or animal waste, especially in warmer months.

Habitat

Filth flies are highly adaptable and can infest both indoor and outdoor spaces. They are often found in kitchens, near garbage bins, and around animal enclosures. Filth flies are attracted to the smell of decay, so foul odors are a sure sign they’re nearby.

For filth flies, odor-based traps are highly effective. The RESCUE! Disposable Fly Trap, POP! Fly Trap, and Reusable Fly Trap are designed to lure filth flies in and keep them trapped, preventing them from reproducing and spreading disease. It’s important to note that these traps are designed strictly for outdoor use. If you need to kill flies indoors, FlyPad and Indoor Fly TrapStik are both good choices.

What Are Biting Flies?

Biting flies, as the name suggests, feed on blood. Common examples include horseflies, deer flies, and black flies. Here's how you can tell if you're dealing with biting flies:

Appearance

Biting flies are usually larger and stockier than house flies. Some biting flies also have distinctive wing patterns or shiny, colorful eyes.

Behavior

These flies are aggressive. They often target animals and humans, drawn by body heat, carbon dioxide, and movement. Biting flies are typically found near bodies of water, wooded areas, or fields where animals graze.

Habitat

Biting flies prefer outdoor environments and are more common in the summer. They are rarely seen inside homes but can ruin outdoor activities like hiking, picnicking, or working in the yard.

Because they’re visually attracted to movement and dark surfaces, sticky traps with visual lures work best for biting flies. The RESCUE! Deck & Patio Fly TrapStik is designed to catch them on contact, providing an easy, odor-free solution to the problem.
 

Choosing the Right Trap

When choosing a trap, consider the type of fly you’re dealing with:

If you’re dealing with biting flies, opt for a trap with a visual attractant like the Deck & Patio Fly TrapStik.

If filth flies are the problem, go with odor-based attractant traps like the Disposable Fly Trap or the POP! Fly Trap, but remember that you should only use these traps outdoors! For eliminating flies indoors, FlyPad and Indoor Fly TrapStik are the best options.

By correctly identifying whether you have biting or filth flies, you can ensure you're using the most effective trap to keep your home and yard fly-free!