A popular fishing lake in Park County is closed to boats, the first body of water in Colorado to be declared off-limits to boats because of the recent discovery of invasive zebra mussels in Pueblo Reservoir.

   The boat ban is in effect for Antero Reservoir, west of Hartsel on U.S. Highway 24, until an inspection system can be set up, reservoir owner Denver Water Board announced Friday.

   Officials from other area water-management agencies, including Colorado Springs Utilities, Colorado State Parks and the U.S. Bureau of Reclamation, said there are no plans to close other lakes to boaters, for now. Plans are in the works for boat inspections at many of the lakes.

   Denver water officials decided to ban boats now because the boating season is almost here. The other reservoir the utility owns where boats are allowed remains iced over.

   "These critters are really nasty," said Neil Sperandeo, the Denver Water Board's recreation manager. "They can clog pipes, from a water utility standpoint. They can ruin boat engines."

   The fingertip-size mussels arrived at the Great Lakes from eastern Europe in oceangoing ships in the late 1980s. With no natural predators, the mussels have spread through most of the Midwest rapidly, hitching rides with recreational boaters.

   Along with clogging water pipes and littering beaches, the mussels can damage a lake by eating all the plankton and driving out native species.

   The mussels were discovered last fall at Pueblo Reservoir, the first time they were found in Colorado. Colorado State Parks, which controls boating there, has launched an inspection system, checking boats as they enter and leave the lake. Any boat with the mussels can be impounded.

   Sperandeo said Lake Antero is used by about 50 fishing boats a day. He did not know when it would be reopened to boats. He noted that fishing from the shore is permitted.

   Antero Reservoir was reopened last year after being closed for five years. It was drained to provide water for Denver during drought years.

   A bill moving through the General Assembly would let officials stop boats on the highways at the borders to inspect for zebra mussels.

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