A Retrospective of the Cherry Creek Westslope Cutthroat Trout Introduction Project, 1997-2011

The use of piscicides to remove non-native fish has become increasingly common in conservation programs focused on preserving and restoring native salmonid fishes in the intermountain west.  The Cherry Creek Project, Madison County, Montana, was initiated by Montana Fish Wildlife and Parks, Turner Enterprises, and Gallatin NF in 1997 with a goal of introducing sensitive native westslope cutthroat trout (Oncorhynchus clarkii lewisi) to approximately 100 km of perennial headwater streams protected by barrier falls.  This area is east of the continental divide in Montana – where westslope cutthroat trout persist in only 5% of their historical range – and was historically fishless, but stocked with non-native species in the early 1900’s.  The project area was broken into four sections or “phases” to facilitate treatment.  Annual treatments focused on a single phase.  Phases were isolated from each other by temporary fish migration barriers and each phase was treated at least two times, usually in consecutive years.  The Cherry Creek Project was delayed by legal challenge in both state and federal court but field work was initiated in 2003.  Piscicide application concluded with successful treatment of the fourth phase in 2010.  Obstacles such as ineffective chemical stocks; non-native fish reinvasion past temporary barriers; high flows; landowner concerns, and chemical escapement were overcome during the course of the project.  Restocking of westslope cutthroat trout, primarily through the use of remote streamside incubators, began in 2006 and over 45,000 eggs from multiple genetic stocks have been introduced.  Parallel to the watershed renovation of Cherry Creek are research efforts concerning the impacts of piscicides on non-target organisms and the most suitable source stock of fish to repopulate the project area.  Summaries of these efforts are being presented during this symposium.  Much work remains to be done on the Cherry Creek project, including continued introductions, monitoring of population recovery, and assessment of treatment effectiveness.  However, the effort to renovate the Cherry Creek watershed, one of the largest piscicide treatments ever conducted in the intermountain west, appears to have been successful.  We believe this success can be attributed in large part to: public outreach; preparation, dedication, and perseverance of federal, state, and private biologists; a goal orientated and well organized collaborative process; and steady support from agency administration.  We hope the success achieved and lessons learned on Cherry Creek provide a model for native fish conservation and restoration over similar or larger scales in the future.