Lakes: Lakes within Grand Teton National Park are open to fishing year-round with the following exceptions: Rivers and Streams: All cutthroat trout caught in open, moving water must be released to the water immediately from November 1-March 31. December 15-March 31: Snake River is closed to access from the Buffalo Fork confluence at Moran to Menors Ferry at Moose. Buffalo Fork is closed from the east park boundary to the Snake River Confluence in Moran.