Cooperative Fish and Wildlife Research Units Program: Montana Fishery
Education, Research and Technical Assistance for Managing Our Natural Resources

Invasive Lake Trout were first discovered in Yellowstone Lake in 1994. The population quickly grew decimating the native Yellowstone Cutthroat Trout population. Removal efforts of Lake Trout began shortly after the discovery of Lake Trout and has grown into a multi-million dollar operation. Park Service and contract gillnetting crews have removed over 1.7 million Lake Trout from Yellowstone Lake. Original efforts focused on younger smaller Lake Trout. In recent years, the effort to remove larger mature Lake Trout has intensified. Targeting known spawning ground has proven to be a successful strategy for removing large quantities of mature fish. With relatively few confirmed spawning sites on Yellowstone Lake, Park Service Biologists have stressed the need for a better understanding of Lake Trout spawning distribution throughout Yellowstone Lake. Accurate locations of where Lake Trout are spawning will be a great asset to suppression crews on the Lake. The proposed study will monitor movements of Lake Trout on Yellowstone Lake with the objective of confirming previously unknown spawning locations.