Progress on conservation measures for humpback chub and razorback sucker in the Colorado River below Glen Canyon Dam

Authors: David W. Speas

Year: 2009 (xli)

Abstract

In accordance with biological opinions on the operation of Glen Canyon Dam issued in 2007 and 2008, Reclamation is providing financial and technical support to participants of the Glen Canyon Dam Adaptive Management Program (GCDAMP)and other agencies to implement a suite of conservation measures designed to improve knowledge and reduce adverse effects of dam operations on humpback chub Gila cypha and razorback sucker Xyrauchen texanus in the Colorado River in Grand Canyon and the Lake Mead inflow area. Since February 2008, significant progress has been made on most of the conservation measures, particularly 1) successful translocation of humpback chub from the Little Colorado River upstream to a previously unoccupied reach and to another Grand Canyon tributary, Shinumo Creek; 2) establishment and maintenance of a humpback chub refuge at Dexter National Fish Hatchery; 3) evaluation of razorback sucker habitat suitability for potential repatriation efforts in the Lower Grand Canyon and Lake Mead inflow areas; 4) a study to relate river flow variables to ecological attributes of nearshore habitats and use of such habitats by early life stage native and nonnative fish species; 5) continued support of the GCDAMP to conduct nonnative fish control efforts, evaluation of the 2008 high flow experiment, a comprehensive humpback chub conservation plan, and other research and monitoring activities to evaluate effects of federal dam operations; and 6) support for Little Colorado River watershed planning, a genetic biocontrol symposium, and other studies. Interagency coordination and execution of these conservation measures has proven to be rewarding but extraordinarily challenging. Challenges include a wide range of permitting requirements, adherence to various state and federal environmental regulatory guidelines, logistics and communication, labor and financial requirements, public relations, and many other coordination tasks. Nevertheless, implementation of these measures thus far appears to be a significant chapter in the cooperative conservation of native fish in Grand Canyon by state, federal, tribal and private entities.