Status, Distribution, and Conservation of Native Freshwater Fishes of Western North America

Status of June Sucker in Utah Lake and Refuges

Matthew E. Andersen, Christopher J. Keleher, Joshua E. Rasmussen, Eriek S. Hansen, Paul D. Thompson, David W. Speas, M. Douglas Routledge, and Trina N. Hedrick

doi: https://doi.org/10.47886/9781888569896.ch4

ABSTRACT The June sucker Chasmistes liorus is endemic to Utah Lake, Utah. Abundant when first described in the 19th century, the species declined precipitously in the 20th century, leading to it being listed as endangered in 1986. The wild population size at time of listing was estimated to be less than 1,000 and may be even smaller at present. A multi-partner cooperative program was formally established in 2002 with the dual goals of recovering the June sucker and allowing continued operation of water facilities for human use. One recovery action of the program has been collection and artificial propagation of June sucker, yielding more than 46,000 June sucker of varying ages currently being held outside of Utah Lake. Mature fish held in captivity are beginning to contribute to recovery as they and their offspring are released into the lake. Dwindling numbers of wild fish combined with the increasing proportions of stocked fish returning to spawn in the Provo River indicates barriers to recruitment that are being addressed by other program recovery actions. While actions being taken to address environmental threats to June sucker, especially controlling nonnative fishes and habitat alteration, must continue if artificially and naturally produced June sucker are to survive in Utah Lake, the ability of this species to thrive and reproduce in habitats outside of Utah Lake will likely be important to its persistence. Habitat recovery and conservation efforts will be critical for maintaining a diverse environment where both June sucker and Utah sucker Catostomus ardens can survive. Environmental influences in Utah Lake appear to have been important for the evolution of sucker feeding habits and the observed morphologies of the two species. June sucker have been kept from going extinct, but should remain listed as endangered. The goal of this paper is to present information regarding the current status of June sucker and the status of actions to recover this endangered species, currently dominated by the captive propagation efforts.