The Black Fly is a tiny, hump-backed biting fly notorious for swarming in enormous numbers around people and animals in northern forests during late spring and early summer, making outdoor activity miserable in some regions. Females cut skin to feed on blood, causing intensely itchy welts. Larvae filter-feed attached to rocks in fast, clean streams and are important food for fish.
Habitat
Near clean, fast-flowing streams; widespread in northern forests
Diet
Females: blood of mammals and birds. Males and larvae: organic particles filtered from stream flow
How common
Common
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