From Manuscript to Management: Development of a New Assisted Rearing Program for Endangered Klamath Suckers

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

Year: 2016 (xlviii)

Abstract

Decades of inadequately abated natural and anthropogenic threats coupled with competing and often controversial water needs have resulted in the compromised status and endangered listing of numerous freshwater fishes, many of which are now artificially propagated in hatcheries. However, low survival of hatchery-reared fish is a commonly reported problem for many programs, particularly those being implemented in systems with substantial non-native predator populations. Extensive sampling for shortnose (Chasmistes brevirostris) and Lost River sucker (Deltistes luxatus) in the Klamath River Basin have failed to detect any new adult recruitment for at least two decades, elevating concern that senescence of the population will result in the demise of thespecies and prompting an investigation into propagation. Balancing the risks of interfering with natural ecological and evolutionary processes for the good of the species requires a substantial investment in recognizing synergies within the existing knowledge base prior to moving forward with program design. As such, the Klamath Falls Fish and Wildlife Office is developing a new assisted rearing program designed to address the need to minimize human intervention in the rearing process and alleviate risks associated with domestication. Wild-spawned fish are collected in relatively low numbers as larvae or young juveniles and reared in a series of earthen ponds that are operated as semi-natural mesocosms, and success to date has been promising. We provide an overview of how key concepts identified in academic literature are incorporated into management actions associated with this program, and an update on the evolution of local, community-based pre-outreach strategies.