The secret weapon for combatting black flies

BANGOR DAILY NEWS • May 20, 2026

Jokingly referred to as the “Maine State Bird,” black flies are one aspect of the Maine outdoors that most people would prefer didn’t exist. The female black fly feeds on blood for the nutrients it needs to lay hundreds of eggs. Black flies also contribute to a healthy freshwater ecosystem, serving as food for a wide variety of larger animals, including Maine native brook trout. While black flies can’t be avoided entirely, there are many things you can do to lessen the number of times you’re bitten when spending time outdoors. In addition to wearing repellent, it can be helpful to wear a hat, which will prevent black flies from crawling into your hair and biting your scalp. Glasses or sunglasses will shield your eyes, which black flies tend to be drawn to. “We suggest people who are gardening put a hardhat on and smear it with baby oil,” said Jim Dill, a pest management specialist with UMaine Cooperative Extension. “Those [black flies] will get stuck in the baby oil.”