Assessment of Short‐Term Mortality of Wild‐Caught Female Walleye Broodstock

The collection of Walleye Sander vitreus eggs to meet stocking needs is an essential part of Walleye management for many state and provincial agencies. The stress of capture, holding, and stripping gametes from wild broodstock can potentially lead to Walleye mortality. In waters < 1,200 ha, high levels of mortality could alter population size structure and affect angler success, future egg collections, and survival of stocked Walleyes. We quantified short‐term (i.e., 5 d) mortality of female Walleyes during artificial spawning operations during 2015 to 2017 in four eastern South Dakota natural lakes (Swan Lake in 2015, Long Lake in 2016, and Antelope Lake and Reid Lake in 2017). Each year 25 female Walleyes were stripped of their eggs and 25 additional female Walleyes were included as reference fish. No Walleyes died in 2015, four fish that were stripped of eggs at Long Lake died in 2016, and one stripped of eggs at Reid Lake died in 2017. Overall short‐term mortality was low (5 of 73 fish, 6.8%) during the study. No reference fish expired during the 3 years. Contusions were apparent on ovaries of both egg‐stripped and reference fish. We believe that if fisheries personnel follow standard artificial spawning procedures for Walleye the amount of mortality will be low and should not impact populations of mature female Walleyes.