Status of least chub, Iotichthys phlegethontis, in Utah

Authors: Cassie D. Mellon

Year: 2010 (xlii)

Abstract

The least chub Iotichthys phlegethontis is a small monotypic minnow endemic to the Bonneville Basin of Utah. Utah Division of Wildlife Resources considers the least chub to be a Tier I sensitive species which is managed under a voluntary multi-agency conservation agreement and strategy established in1998. A proposed listing of least chub under the Endangered Species Act was withdrawn by the U.S. Fish and Wildlife Service (Service) in 1999 due to conservation actions established in the conservation agreement and strategy. The least chub was again petitioned for listing in 1997 and in 2010, the Service found listing of least chub as warranted but precluded. Many conservation actions such as: habitat enhancement, securing water rights to protect instream flow, creation of refuge populations, and non-native fish removal have been undertaken by the conservation team and have had great benefits to least chub. One novel conservation action has shown great promise for least chub conservation. In 2010, the Salt Lake City Mosquito Abatement District replaced the use of non-native western mosquitofish, Gambusia affinis, with least chub for mosquito control in backyard ponds. This has been a successful transition from use of a highly invasive nonnative to a native fish with the same desired effect of effective mosquito control, and an important benefit of public education. In spite of all the work that has gone into least chub conservation, there are still threats to the long-term persistence of least chub, primarily water withdrawal and the spread of invasive nonnative fish.