The larva is an active stage that feeds while floating at the water surface. They get air at the water surface through a snorkel-like device. They can swim down from the surface but need to return to it shortly in order to breathe. Larva are filter feeders, eating organic matter in the water, which they collect by using their bristle-like mouthparts. The third life stage is the pupa.
Pupae are comma-shaped and stay at the water surface.
If disturbed, they tumble downward to escape. Pupae do not feed. This stage lasts only for two or three days. Both larvae and pupae are subject to heavy predation. Typically, the 100-400 eggs laid by a female only result in a few adults developing successfully.