Razorback Sucker, Xyrauchen texanus, Research and Monitoring in the Colorado River Inflow Area of Lake Mead and the Lower Grand Canyon, Arizona and Nevada

Authors: Brandon Albrecht

Year: 2014 (xlvi)

Abstract

Based on past studies and recent movements of sonic-tagged Razorback Suckers from Lake Mead into the lower Grand Canyon (LGC) section of the Colorado River, questions regarding this population have spurred further interest into the presence of wild individuals and their relationship between the river and reservoir. For more than 20 years, Razorback Suckers were thought to be extirpated within the Grand Canyon. This collaborative and holistic study included efforts to continue monitoring of Razorback Sucker (all life stages) within the Colorado River inflow of Lake Mead (CRI) coupled with the recent inclusion of sonic telemetry, small-bodied fish community, and larval fish community sampling from Lava Falls downstream to Pearce Ferry, in the LGC (RM 180-280). The specific objectives outlined for these efforts include; (1) conducting larval and small-bodied fish studies to quantitatively assess annual fish reproduction, spawning, and nursery areas in the LGC, (2) determine if Razorback Suckers are present in the study area and if they associate with habitat found within the LGC through telemetry and opportunistic adult sampling, and (3) to help determine habitat associations, relative spawning and reproductive effort, and population trends of Razorback Sucker in the CRI and LGC. Specifically, this paper will provide an overview for this work and will cover findings from the CRI portion of this multi-faceted study, particularly regarding natural recruitment observed within this population. Subsequent papers will provide specific insights into the telemetry and small-bodied fish community sampling, as well as findings to date from the larval fish community sampling in the LGC.

Resumen

Entra texto de resumen en español