Toston Dam is threatened with environmental degradation due to invasive species. In 2009, the Montana Department of Fish, Wildlife and Parks (FWP) warned that the reservoir had been invaded by northern pike which had escaped from private ponds upstream.Henckel, Mark. "Pike Create New Fishery Above Toston Dam." Billings Gazette. March 18, 2009. Northern pike are an aggressive predatory fish which feed on trout and other species highly prized by fishermen. A year later, the state sought approval to remove the limit on daily catches of northern pike to protect several trout species, which had come under severe pressure from the pike.Evaro, Donna. "FWP Seeks Comments on Fishing Regulations for Season Starting in March." Great Falls Tribune. August 12, 2010. In April 2011, the pike problem became so severe that the FWP announced an even more aggressive plan to try to remove the predatory fish from Toston Reservoir and other upstream waters.Byron, Eve. "FWP Seeks to Remove Northern Pike From Missouri Headwaters." Helena Independent Record. April 10, 2011.
