Grand Mesa: Rotenone to be used to reclaim Water Dog Reservoir


Here’s the release from Colorado Parks and Wildlife:

The public is advised that Colorado Parks and Wildlife will be reclaiming Water Dog Reservoir to remove white suckers beginning Sept. 5. The reservoir is located on the Grand Mesa, east of Grand Junction. Lands around the reservoir are managed by the U.S. Forest Service. Anglers and others engaged in recreation in the area are asked to observe posted signs and avoid the area around the reservoir until further notice. Wildlife managers expect the project will be completed by the middle of October.

The most recent survey performed by wildlife managers found only white suckers present in the reservoir. Wildlife managers say that white suckers, likely introduced by anglers using them as live bait, can displace rainbow trout.

Once the work is complete, Colorado Parks and Wildlife plans to stock rainbow trout into the reservoir in the early summer of 2013.

“Water Dog is a productive reservoir and had been an excellent rainbow trout fishery,” said Lori Martin, aquatic biologist from Grand Junction. “Because there are only white suckers in the reservoir, and the current water volume is low, it gives us an opportunity to eliminate the suckers and restore the sport fishery.”

At full capacity, the reservoir is approximately 24 surface acres, but it was recently drawn down to approximately 15 surface acres to meet the needs of downstream water users.

White suckers will be removed through the application of rotenone, a toxicant derived from a South American plant. Rotenone has been used as a fisheries management tool throughout Colorado and the United States for decades because it degrades quickly and poses no danger to other wildlife or humans.

Application will be carefully controlled and the water will be monitored afterward by aquatic biologists from Colorado Parks and Wildlife. No treated water will be released from the project area before detoxification of the water is confirmed.

Dead fish will be left to decompose naturally to recycle important nutrients as the reservoir fills. The public is prohibited from harvesting fish killed by the project, and people are asked to avoid the reservoir while the project is underway.

“We look forward to restoring Water Dog Reservoir as a great place for anglers to catch rainbows,” said Martin. “We encourage anglers to be ethical and follow fishing rules and regulations to prevent live baitfish from establishing populations that will negatively impact our sport fisheries.”

Wildlife managers remind the public that with the exception of Navajo Reservoir, the use of live fish as bait is illegal in all waters west of the Continental Divide in Colorado. Violators can face significant fines and the permanent loss of hunting and fishing privileges. For more information about angling ethics, please visit:

More restoration/reclamation coverage here.

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