Management of a New Assisted Rearing Program for Endangered Klamath Lake Suckers

Authors: Kirk Groves, Ron Barnes, Julie Day, Darrick Weissenfluh

Year: 2016 (xlviii)

Abstract

The U.S. Fish and Wildlife Service (USFWS) initiated a new Sucker Assisted Rearing Program (SARP) in 2015 with the goal of collecting and rearing 8,000-10,000 endangered Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) for release into the Upper Klamath Lake system. Unlike many captive propagation programs, SARP is designed to minimize the need for human intervention in the rearing process by catching and rearing wild-spawned larvae in lieu of direct gamete collections, limiting the amount of time fish spend in artificial holding environments, and avoiding the use of intensive fish culture met hods to the extent possible. The priority objective for this program is to maximize the likelihood of fish survival upon release. Larvae are transported to a private rearing facility leased and operated by USFWS where they receive health and behavioral evaluations b efore being stocked into lined earthen ponds supplied with geothermal water that are managed to mimic conditions fish would experience in the wild. Here we present results from the first year of collection and husbandry activities, rearing facility expansion process, and year-two objectives. Collections and rearing were largely successful in 2016 and efforts will increase in 2017 with the assistance of Bureau of Reclamation and The Klamath Tribes biologists. The newly redesigned facility was completed in fall 2016 and triples our husbandry capacity to better suit the program as well as manage it in a manner that affords opportunities for modification as the program evolves. This will allow SARP to rear suckers in low densities, minimize stress, provide enrichme nt, and investigate experimental fish health treatments.