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Fly Control for Commercial Premises
What are sand flies?
Sand flies are tiny, biting insects that live in warm, sandy areas. These pests are a big problem near beaches, where they bite people and leave itchy, red marks. They can also spread diseases, making them more than just a nuisance.
Key characteristics
Sand flies are small insects that move by hopping, not flying. Female sand flies bite humans and animals to get blood for laying eggs. Sand flies are often mistaken for mosquitoes. Unlike mosquitoes, they do not make a buzzing sound when flying. Their bites are painful and can appear in clusters on the skin.
Appearance
- Adult — 3/8"–7/16". The body is pale grey, the eyes are bronze–brown, and the legs are dark reddish–brown.
- Hold their wings in a V-shape when resting.
The life cycle of sand flies
Sand flies go through four life stages: egg, larva, pupa, and adult. The female lays eggs in damp soil, cracks in walls, or decaying plants. The larvae hatch and feed on organic material before turning into pupae. The larvae can take up to two years to develop and live in loose sand. In the pupal stage, the larvae curl into a circle or "U" shape, and this stage lasts one to two weeks. Afterward, the pupae turn into adults in about seven to 10 days. Most adult sand flies live for just a few weeks and are seen from April to September.
Seasonal behaviors of sand flies
Sand flies are most active during the summer and fall, especially in warm, humid areas. They usually bite at dawn and dusk, when temperatures are cooler and the wind is calm.
Habitat and diet of sand flies
Sand flies thrive in warm, humid environments. The adults tend to live on sandy riverbanks with an open habitat free of shading trees. The larvae of sand flies are active soil predators.
Where do sand flies live?
Sand flies prefer warm, damp environments. They are commonly found on sandy riverbanks and beaches, which is why they are sometimes called beach flies or biting sand gnats. They also live in swamps, marshes, farms, and gardens, where they can hide in damp soil. In homes, sand flies may nest in basements, cracks, and drains.
What do sand flies eat?
Both male and female sand flies feed on nectar and plant juices. However, females need blood meals to lay eggs.
Habits and behavior of sand flies
Sand flies are nocturnal and most active at night. They do not fly far and prefer to stay in shaded areas. Unlike mosquitoes, they do not make noise when flying, so people often don’t notice them until they feel a bite. Sand flies are known for carrying tropical diseases, including leishmaniasis, which can cause serious skin sores and infections.
Managing and preventing sand fly infestations
Preventing sand flies starts with reducing moisture, sealing entry points, and using repellents to keep them away.
Signs of an infestation
If you notice clusters of itchy red bites, especially on your ankles and legs, you may have sand flies nearby. They tend to gather in humid, shaded areas and may be seen hovering around windows, drains, and wet soil.
How to get rid of sand flies
To prevent sand flies, remove standing water and damp organic material where they lay eggs. Keep windows and doors screened to stop them from getting inside. Turning off outdoor lights at night can also help as they are attracted to light.
If you get bitten by a sand fly, seek medical advice, as their bites can sometimes cause health problems.
If you are struggling with a serious sand fly infestation, contact our fly control experts.
Frequently asked questions
What happens if you get bitten by sand flies?
Sand fly bites can cause redness, swelling, and itching. Some people may have an allergic reaction, leading to more severe irritation or skin infections. If symptoms worsen or signs of infection appear, seek medical advice.
Are sand flies harmful?
Yes, sand flies can be harmful. Their bites are painful and can cause skin irritation. Some species spread diseases like leishmaniasis, which can cause serious health problems.
What attracts sand flies?
Sand flies are drawn to moist, shaded areas, human body heat, and exposed skin. Wearing dark clothing can also increase the likelihood of getting bitten.
Is a sand fly a mosquito?
No, sand flies and mosquitoes are different insects. While both bite and feed on blood, sand flies are smaller and have a hopping movement instead of a smooth flight.
Other types of flies
Learn more about other common flies found in the US, including lesser house flies, crane flies, and autumn flies.
Lesser house flies are small, grayish flies with darker stripes on their thorax, often found in decaying organic matter.
Autumn flies, known for clustering around windows in cooler months, invade homes seeking warmth.
Drain flies are small, dark-colored insects often found near sinks, drains, and sewage systems.