The trout at Antero Reservoir are in trouble. Again.
A dense and unmoving snow cap has caused levels of dissolved oxygen to plummet near the danger point, placing thousands of trophy fish in peril.
In response, the Colorado Division of Wildlife is poised to use heavy equipment to remove crusted snow in key areas to promote their survival.
Biologist Jeff Spohn recently found oxygen levels ranging midway between 3 and 4 parts per million, a reading that could result in extensive mortality. The large trout that make this the state’s premiere still-water fishery are most susceptible to oxygen deficiency. Even smaller fish might succumb at these levels.
Compacted snow ranging from 5-10 inches deep keeps light from reaching the dense aquatic vegetation below the surface. When the vegetation dies, oxygen is removed during the decaying process. The 2,200-surface-acre impoundment historically has been susceptible to winter kill.
More recently, it was drained and closed to fishing for five years in the aftermath of the 2002 drought. When it reopened last July, anglers immediately found superb action and exceptionally large trout.
Spohn and his crew are testing the ice to identify large areas where it will support snow-moving machinery.
“There are no guarantees we’ll be successful, but we’re trying to be proactive,” Spohn said. “We’ve worked very hard the last 3 1/2 years to establish this fishery. We’d hate to lose it.”
The notion, Spohn said, is to establish zones where plants will remain alive as places of refuge for stressed trout.
Sanctuary already exists in four places with limited areas of open water. The lake also features a number of underwater springs.
Spohn said ice depth across much of the lake ranges from 11 to 20 1/2 inches.
Charlie Meyers
