The Suppression of Northern Pike Esox lucius in Box Canyon Reservoir, Pend Oreille River, Washington

Northern Pike Esox lucius recently established Washington's first reproducing population in the Pend Oreille River, making it an ecological threat throughout the region.  Considering that the Pend Oreille is a tributary of the Columbia River, the possibility of downstream expansion threatens many species, including salmon and steelhead.  Surveys conducted by the Washington Department of Fish and Wildlife (WDFW) and the Kalispel Tribe of Indians Natural Resources Department (KNRD) from 2004 to 2011 documented both a rapid increase in the number of Northern Pike and a decline in the abundance of most forage species.  In 2011, Washington, faced with accepting Northern Pike as a great new sport fish or treating it as an invasive species, reclassified Northern Pike as a prohibited species.  In February 2012, WDFW and KNRD initiated a multi-year campaign to reduce Northern Pike numbers in Box Canyon Reservoir, on the Pend Oreille River.  Suppression methods included: angler harvest, fishing derbies, and active removal using gill nets.  Over 16,000 Northern Pike were removed from the population in three years, an estimated 90% reduction, reducing the risk of downstream expansion.  However, suppression efforts continue and co-managers are working to develop a long-term Northern Pike management strategy for the region.