Black flies, known for their persistent biting behavior, can distract drivers and potentially lead to accidents if they swarm around vehicles or if drivers become preoccupied with trying to avoid them.

Black flies in Michigan are typically active from late spring to early summer, with their peak activity occurring in May and June. These insects thrive in cool, moist environments, especially near rivers, streams, and wooded areas. The exact timing of their emergence and activity can vary depending on factors such as temperature, precipitation, and local environmental conditions. Typically, they are most prevalent during daylight hours and are less active in the evening and at night.

Black flies, like many other insects, can indeed smear windshields when they are abundant. This can impair visibility and pose a hazard to drivers, especially if the smearing is significant or if it occurs suddenly while driving at higher speeds.

Michigan State Police advise:

1. Keeping windows closed or use screens to prevent black flies from entering the vehicle.
2. Using windshield washer fluid with insect-dissolving properties to clear the windshield until you can safely pull over to the side of the road.
3. Keeping windshield wipers in good condition and use them as needed. However, using your wipers will smear the insect residue.
4. If your visibility is reduced by insect smearing on your windshield safely pull over to the side of the road and clear the windshield using a Bugs Off Pad and water from a bottle, not a chemical bug remover as these need to be rinsed off and the chemicals themselves will then smear the windshield.
5. Be cautious and prepared to react if visibility is suddenly reduced due to insect smearing on the windshield.