Skip to main content
U.S. flag

An official website of the United States government

Midge eggs (an aquatic winged insect) laid on a rock in the Colorado River, Grand Canyon

Detailed Description

Some aquatic insects in the Colorado River, Grand Canyon, lay their eggs on rocks along the waterline. If the river level drops, the eggs dry out and die. SBSC, Grand Canyon Monitoring and Research Center scientists are studying insect populations during modified hydropower flows from Glen Canyon Dam, called "Bug Flows," that are designed to provide steady water releases on weekends to enable more eggs to hatch. Bug Flows may have positive effects on fish, bats and birds that prey on the insects.

Sources/Usage

Public Domain.

Image provided to USGS, Southwest Biological Science Center. To use image, request permission from David Herasimtschuk, Freshwaters Illustrated.

Was this page helpful?