Colorado Parks and Wildlife is improving Summit Reservoir fish habitat with an innovative approach: big tree stumps.
Six ponderosa pine stumps weighing between 800 and 1,600 pounds were dragged onto the ice last week.
When the ice melts, they will sink to the bottom and provide structure habitat for various fish species, said CPW wildlife technician Ryan Lane.
As an irrigation reservoir, Summit does not have good habitat for hiding and spawning.
“The lake bottom is really flat. We got approval from reservoir officials to add these to give fish some cover and a place to reproduce,” Lane said.
CPW stocks Summit with perch, crappie, blue gill, large-mouth bass, trout and catfish. The lake, south of Dolores off Colorado Highway 184, is a state wildlife area and is a popular year-round fishing spot for locals and tourists.
Lane had the habitat improvement idea while working in the shop at the Dolores River State Wildlife Area last week off Colorado Highway 145.
CPW plans improvements at the site, and in August removed six large ponderosa pines to make room for a new pole barn.
“I had this brainstorm on how we could use the stumps. We had dug them out, the next challenge was how to get them onto the lake. The thick ice made it possible,” Lane said.
Lane devised a cable-winching system using an anchor positioned under the ice, pulleys, chains, cables and lots of manpower. The stumps were delivered to the lake shore one at a time in a dump-bed trailer.
“It was quite the operation dragging them onto the ice. We’d never done something like this before, but it worked out,” he said.
The stumps were positioned to remain under water when the lake is at its lowest level.
CPW also sinks recycled Christmas trees to add to lake habitat at other wildlife areas. A few years ago on Narraguinnep, 2,500 trees were cabled together, boated out and sunk.
The thick stumps have larger mass and will last longer than the trees, which erode more quickly.
“Once the dirt in the root ball is washed away, there will be many nooks and crannies for the fish to hide and lay eggs,” Lane said.
Smaller panfish such as like perch and crappie need cover to avoid larger predators.
Structures in lake bottoms also attract schools of fish, so casting a line over them can be ideal. Local ice fisherman have taken note of their positions.
“Anything helps,” said Wade Jordan, of Cortez BassMasters.
Lane fishes Summit often with his family. They have noticed fish are spawning in the willows on the lake shore. But the spawning grounds become high and dry when irrigators draw down the lake. Now they have another place to go that stays under water.
“We see it improving fish population, and it helps fishermen too,” he said.
Obtaining the stumps from a nearby project was a unique situation, but CPW says if they come across them again, instead of burning them they can sink them in local lakes.
Puett Reservoir is next on the list for habitat structure improvements, Lane said, hopefully with giant, fish-friendly stumps.
jmimiaga@the-journal.com