Hellgrammite (Dobsonfly Larva)

Natural Habitat

Flowing freshwater streams and rivers with rocky bottoms and high oxygen levels.

Diet & Feeding

Predaceous; they eat other aquatic insects, small crustaceans, and even small fish or tadpoles.

Behavior Patterns

They are primarily nocturnal and stay hidden under rocks in riffles to avoid predators. This stage can last up to 3 years before they pupate and become winged dobsonflies.

Risks & Benefits

They have powerful mandibles and can give a painful pinch if handled. Benefit: They are important indicators of good water quality and are prized as bait by freshwater anglers.

Identified on: 5/18/2026