Wildlife & Nature Do horsehair worms harm fish? February 4, 2026 by Tanp | Leave a Comment Horsehair worms, scientifically known as Nematomorpha, are parasitic worms that primarily target insects such as crickets and grasshoppers. Do horsehair worms harm fish? Generally, horsehair worms do not harm fish. They do not parasitize fish and are not known to cause direct harm to aquatic life. What Are Horsehair Worms? Horsehair worms are long, slender […] Read more ยป