Study Plan - Biological Resource Responses to Fall Steady Experimental Flows Feruary 2010

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Need for Project The Arizona Game and Fish Department (AZGFD) has managed the Lees Ferry recreational fishery since 1964. Lees Ferry serves as a popular destination fishery for international and national anglers. As such, it provides significant contributions to the Marble Canyon business community. The fishery is regulated by biotic and abiotic mechanisms that may in turn be affected by the operations of GCD. The monitoring of basic fish population elements, including abundance and distribution of native and nonnative fishes, provides the information necessary to assess the status of these resources and inform the Glen Canyon Dam Adaptive Management Program (GCDAMP). Strategic Science Questions Primary fall steady flow related SSQs addressed: SSQ 3 -6 What GCD operations (ramping rates, daily flow range, etc.) maximize trout fishing opportunities and catchability? Methods and Tasks Summary of annual monitoring /sampling: • Two standardized random sampling surveys • Two early life history trips (one or both may extend below the Paria River at RM 1) • Creel surveys, funded by AZGFD In monitoring, RBT are sampled using electrofishing to estimate biological parameters and to assess the status and trends of the fishery. This sampling design was developed to ensure managers have a monitoring program with the temporal "power" to detect population trends without biases in site selection, as well as a means to precisely estimate status of the rainbow trout population. Electrofishing provides information on size composition, relative abundance (catch per minute as an index of population size), condition (length- weight relationships), and disease. Electrofishing prior to 2010 occurred 3 times per year with sampling effort stratified over 27 random and 9 fixed sites. Present sampling design can detect a 6 -10% linear change in abundance over a 5 -year period. Work is currently underway to assess the statistical power of intra- and inter - annual comparisons. Over the last 7 years a contractor, Ecometric Research, Inc., has been conducting surveys of RBT redds and early life stages of RBT in the Lees Ferry reach. These studies have been useful, especially in the analysis of dam operation impact to RBT. Similar studies may not be incorporated into long -term monitoring, but in light of the continued experimental operations of Glen Canyon Dam through 2012 the work is to be maintained, at least for FY 2010 -11. In FY 2010 -11 the AZGFD will work cooperatively with Ecometric, Inc. to transfer knowledge regarding the techniques and data analysis from the contractor to the agency, anticipating that AZGFD will be completely responsible for any early life stage monitoring that may be necessary in FY 2012 and beyond. Links /Relationships to Other Projects This project will help inform data on fish and habitat collected at downstream locations. Work by Korman (Gloss and Coggins, 2005; Korman and Campana, 2009) has provided the most conclusive evidence to date of the relationship between dam operations and fish vital rates (i.e., survival). Frequent 29