St. Paul, MN (KROC-AM News) - The Minnesota Department of Natural Resources is giving up on its efforts to rid a Twin Cities area lake of zebra mussels.

Officials say, despite an aggressive treatment program, a reproducing population of the invasive species continues to be present in Christmas Lake. The lake in Hennepin County had undergone multiple treatments as part of an experimental effort to eradicate a population of zebra mussels.

The DNR says the zebra mussels recently found in the lake were not in the area where the treatment was applied and most were juveniles, which indicates reproduction has occurred and the population of the invasive species is scattered across the lake.