Glen Canyon Dam

The image above is a photograph of the Glen Canyon Dam (GCD) in Arizona. Recent captures of non-native fishes in the Colorado River downstream of GCD indicate a potential threat to imperiled native fish in the Grand Canyon. Within the last two years, biological survey teams have observed increasing captures of non-native fish species including smallmouth bass, green sunfish, and bluegill throughout the Lees Ferry Reach (approximately 15 river miles from GCD).