Mancos River project helps irrigation, fish habitat
New water barriers on stretch of river from Excelsior plant to Road J bridge create pools for suckers
A short stretch of the Mancos River is now more fish-friendly after extensive work by the Mancos Conservation District.
The district received $120,000 to improve four diversions and increase habitat diversity along 2.4 miles of the river from the Western Excelsior Plant to the Road J bridge, said Russell Klatt, the natural resource technician for the district.
Before the work was started, an unusually large number of pure bluehead suckers was found in the river by an electro-fishing survey by the Colorado Parks and Wildlife. A total of 45 suckers was found in about 1,000 feet of river. The survey also found brown and rainbow trout.
In many other parts of the Colorado, the bluehead sucker has crossbred with non-native suckers, said Jim White, an aquatic biologist with Colorado Parks and Wildlife, who did the survey.
It is also rare to find the suckers in habitats that are affected by a lot of irrigation like the Mancos, he said.
"A bluehead sucker is kind of like a cow - they graze in shallow rippling water," White said.
But during the day the fish, which range from 3 to 7 inches in the Mancos River, like to hide in pools under tree branches. When the water gets warmer in summer, the fish head upstream for cooler streams.
So downstream from the Road J bridge, the district installed several weirs to eliminate a sharp drop of several feet that created a barrier for the small fish.
Other weirs were created to slow the water down and create pools for fish to live in during the day and when the river is low.
The project was completed in September and October on private land.
White said that combining habitat improvement with irrigation improvement was important in Colorado for projects to succeed.
"You really got to have that public-private spirit of working together," he said.
The grant also funded the replacement of two unstable cobble diversions with permanent weirs.
These weirs are made out boulders about a cubic yard in size and make it easier for local farmers to receive a good flow of water in the spring.
Klatt said he plans to improve two more diversions with the grant funding this winter or after irrigation season in the fall.