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<br />. <br /> <br />DRAFT <br /> <br />'II. Conduct research to identify limiting and beneficial imp<l.cts of Glen. <br />Canyon Dam (Glen Canyon) operation on the hun.pback chub in the mainstream <br />and tributaries in the project area. Use this information to ensure that <br />all phases of the Glen Canyon operation contribute to the continued <br />n,aintenance and the likelihood for recovery of the species in the <br />mainstream and tributaries, <br /> <br />A. <br /> <br />Objectives <br /> <br />1. Detenliine habitat use for all life stages (egg, larvae, juvenile, and <br />adult) throughout the year in the mainstrean. and tributaries in the <br />project area, Macro- and micro-habitat . utilization data concerning <br />geologic substrate, depth, velocity, cover, water quality, and other <br />appropriate cOlliponents will be collected to cbaracterize the habitat, <br />Primary eruphasis in the ruainstream will be babitats, such as backwaters, <br />that are influenced by operations; however, all habitat use will be <br />doculllented. ~lovellients of various life ;stages will be investigated to <br />assist in deterffiining seasonal use and to identify the degree of <br />isolation, if any, that may exist alllong the humpback chub in the project <br />.:tr(?t1 . <br /> <br />~ Determine habitat availability under the range of Glen Canyon's <br />operational regimes and test for habitat selection by the humpback <br />chub. Particular attention will be directed towards flow regimes <br />identified in the COIi.missioner of Reclamation's menlorandum of December, <br />1982 which included low flows of 1.000, 3,000, 4,000, 5,000 and 8,000 <br />cubic feet per second and fluctuating flow regimes together with flow <br />patterns that may be identified as being either limiting or essential to <br />various life stages of the hunlpback chub. Antecedent flows will be an <br />important factor in determining study situations. Flow regimes necessary <br />to conduct critical studies will be identified ~uring the first year of <br />the study. 'I'he ability to provide requested flows may be crucial to the <br />timely completion of the studies and the continuance of the no jeopardy <br />opinion. Othcr factors that may influence habitat selection or use, such <br />as ~nvironl"ental contaminants and recreational use, will also be <br />investigated. <br /> <br />3. Determine food resource needs and availability for all feeding stages <br />in lllaillstrealll and tributary habitats. Determine the i<<lpact of Glen <br />Canyon's operation on those resources. <br /> <br />4. Deten"ine biOlogical interactions including competition, parasitism <br />and predation under current operations or future operations which may be <br />implemented as a result of these studies. Collect information of species <br />found in association with the hUUlpback chub. <br /> <br />5. Detenlline agel growth and agelf eeundi ty relationships f or humpback <br />chub and the effect of project operation, inc1uding water temperature, on <br />these relationships. <br /> <br />G. Develop or modify an existing population model for empirical <br />de terlllina t ion of reproduct i ve success, recruitllJent, and morta li ty <br />rates. <br /> <br />) <br /> <br />r: <br />I',; <br /> <br />i <br /> <br />,. <br /> <br />,. <br /> <br />",' <br />t~ <br />" <br />11 <br /> <br />-1;1\ <br /> <br />'. <br /> <br />~-' <br /> <br />"I <br />" , <br /> <br />1..-<1 <br />""I. <br />t1r: <br />~~;~ <br /> <br />l <br /> <br />