LAS VEGAS (KLAS) — Smallmouth bass simply misplaced considered one of their favourite locations to spawn within the Colorado River under Glen Canyon Dam, in line with a Thursday information launch from the Nationwide Park Service.
The water is transferring once more and the temperature is cooling down 3.5 miles previous the dam after staff cleared a shallow slough the place the river splits round a sandbar. The location, about 12 river miles upstream of Lees Ferry, Arizona, is the most recent battleground in preventing the invasive smallmouth bass, which presents a menace to the humpback chub, which is federally protected.
Chilly shot fired in battle over Colorado River invaders
The continued drought within the Southwest U.S. has contributed to decrease elevations at Lake Powell, and hotter water from the floor is nearer to the dam’s intakes. That is offering a method for the fish to get by means of the dam and set up populations within the river.
Officers stated the water now strikes by means of a channel created on the bottom of the sandbar. The place it was as soon as nonetheless, the water is transferring now at about one foot per second, bringing cooler water and disrupting spawning.
A earlier than (left) and after (proper) view of the challenge exhibits the channel flowing across the sandbar after the slough was cleared. (Photographs: Nationwide Park Service)
In earlier years, a “high-flow experiment” at Glen Canyon Dam occurred usually sufficient to churn up sand settled within the riverbed and reshape sandbars downstream. However that is not occurring proper now as work continues on recoating the within of the pipes — the “river outlet works” — used for that high-volume launch.
Now, officers are utilizing a mix of methods to disrupt spawning, together with “chemical and mechanical removal of nonnative species and the use of ‘cool mix’ flows — pulling colder water from deeper within Lake Powell to cool the river below the dam, creating unfavorable conditions for warmwater fish. Long-term methods to control bass populations below the dam are being explored” by the U.S. Bureau of Reclamation and the Nationwide Park Service.
Glen Canyon Dam floor zero for conflict on invasive smallmouth bass in Colorado River
“The channelization project aims to protect native fish including the threatened humpback chub, endangered razorback sucker, and flannelmouth sucker by limiting smallmouth bass reproduction. The channelization may also benefit the rainbow trout population at Lees Ferry, already observed in the new channel,” the information launch stated.
“This channelization effort demonstrates the power of partnerships and adaptive management in protecting the Colorado River ecosystem,” Reclamation Higher Colorado Basin Regional Director Wayne Pullan stated.
Throughout the channel challenge, particular care was taken to guard native wildlife, significantly salamanders that are not often seen within the canyon. The Nationwide Park Service adjusted the design to make sure safety of springs situated throughout the challenge web site.
