The National Park Service began electrofishing in the Colorado River this week to kill smallmouth bass between Glen Canyon Dam and Lees Ferry. KNAU’s Melissa Sevigny reports, it follows an unsuccessful attempt to control the exotic fish by poisoning a nearby slough.
Smallmouth bass have been slipping through the dam due to the low water levels. Last month the Park Service poisoned a slough connected to the river where the fish had been found. The effort eliminated tens of thousands of exotic carp, but almost no bass were counted. Most likely they had already escaped into the main channel.
Park Service biologist Melissa Trammell says the agency will test the effectiveness of electrofishing over the next six weeks. "We think elimination is unlikely but we can greatly reduce their numbers in that reach, we think. That would be helpful to avoid downstream dispersal of the smallmouth bass into the rest of the Grand Canyon," she says.
The Pueblo of Zuni has objected to electrofishing in the Colorado River in the past for cultural and spiritual reasons. The tribe’s fish and wildlife office did not immediately respond to KNAU’s request for comment.
