Midwest Fish & Wildlife Conference 2018

AUTHORS. Dave Spalsbury, Susan Steffen - Kansas Department of Wildlife, Parks, and Tourism

ABSTRACT. Cedar Bluff Reservoir, Trego Co., KS is an impoundment of the Smoky Hill River in western Kansas completed in 1951 and characterized by widely fluctuating water level. Walleye were first introduced in 1953 with harvest regulated by a 5 fish/day creel limit since initial introduction and an 18” minimum length limit (MLL) implemented in 1990.  Since 2001 stocking consisted of two disparate stockings thus natural production and recruitment, coupled with a lag in angler harvest, fostered development of a population characterized by sufficient quality dynamics to support egg collection for Kansas hatchery production.  Cedar Bluff has been an important egg source since 2006.  Decreased trends in abundance of larger walleye were documented by standard sampling and spring egg collection efforts in recent years.  Sex-specific population age structure was determined from otoliths collected during spring 2017 and growth was similar to that documented in 2010 and 2011.  Anectdotal evidence, supported by trends in annual state park visitation during March to May and angler preference documented by creel surveys indicated that walleye fishing pressure had increased.  The most recent creel survey conducted in 2014 documented; high harvest from March to October at 5,620 walleye (1.86 walleye/ac.), nearly 100% of fish 18” and larger caught were harvested, and walleye was the most preferred sportfish by anglers.    Taken together, good recent production and recruitment, no to minimal decrease in growth despite increased abundance, and high walleye specific angling pressure and harvest made it apparent that recruitment overfishing limited abundance of larger walleye.  To allow recovery of size structure and optimize reproductive potential, a proposal to implement a 21” MLL on walleye harvest was made.