June Sucker Post-stocking Evaluation

Authors: Wesley Goldsmith, Paul Marsh, Brian Kesner, Chase Ehlo

Year: 2016 (xlviii)

Abstract

June sucker, Chasmistes liorus, is an endangered species endemic to Utah Lake, Utah. Through anthropogenic disturbances and introduction of non-native fishes, June sucker populations drastically declined. Population augmentation is currently the main component of the June Sucker Recovery Implementation Program, but post-stocking survival of hatchery reared June sucker is not fully understood. Twenty-four June sucker (twelve each of age 1 and age 2 individuals) were surgically implanted with acoustic tags and released on 3 June 2016 along with two cohorts of PIT tagged fish (1,470 age 1 and 1,466 age 2).After 60 days of ac tive and passive tracking, fish were classified as alive, a mortality, or lost to the study. Of the twelve age 1 fish, one was alive, three were mortalities, and eight were lost to the study. Of the twelve age 2 fish, five were alive, one was a mortality, and six were lost to the study. In addition to acoustic telemetry, PIT scanning was also employed in an effort to evaluate post-stocking survival. Thirty submersible PIT scanning units were placed throughout the lake at random locations and in known high traffic areas. Scanners contacted 742 individual June sucker, of which 176 had a stocking record. Of the fish with stocking records 59.7% were stocked in 2011 and had an average total length of 309 mm. Both acoustic telemetry and remote PIT scanning is an effective method of evaluating post-stocking survival of June sucker. Based on these data, we recommend stocking age 2 June sucker for the continued conservation and eventual recovery of the species.