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<br />~ <br /> <br />~ <br /> <br />V. Study Methods/Approach: <br /> <br />Two reaches in the upper and lower portions of the standardized <br />monitoring reaches of the lower COlorado River will be selected for <br />intensive sampling. They will be sampled in July and September at a <br />minimum, further sampling dates may be added in subsequent years based <br />on preliminary results. Sampling will be coordinated with standardized <br />monitoring efforts so that duplication will not occur. All backwaters <br />within each station will be sampled. <br /> <br />Video of the stations will be acquired 1 to 2 days prior to sampling and <br />computer images will be taken into the field for ground truthing and <br />identification of specific backwaters. This will be coordinated with <br />the Bureau of Reclamation so that flows do not change substantially <br />between acquiring the video and sampling. Backwaters will be seined to <br />determine whether or not squawfish are present and if so, how many. <br />Physical and biological habitat characteristics of each backwater will <br />also be measured in an attempt to distinguish habitats which are <br />utilized from those which are not. Reach characteristics, such as <br />number or area of backwaters per mile will also be identified as <br />possible indexing factors for standardized monitoring data. <br /> <br />Data will be collected over five field seasons. This is necessary <br />because of differences in the system from year to year and will also <br />give us a chance to refine the study design based on the preliminary <br />data. Possible nursery habitats other than traditional backwaters will <br />also be sampled. Seasonal degree-day accumulation will be measured in <br />selected areas. Data collected on physical and biological habitat <br />characteristics will be analyzed for possible relationships to use by <br />squawfish. <br /> <br />VI. Task Description (FY-1993): <br /> <br />Obtain video at each study reach, 2 times per year. <br />Sample all backwaters in each station for squawfish <br />utilization and ground truth videos. <br />Measure physical and biological habitat characteristics of <br />backwaters in each station. <br />Determine relationships between and area of backwaters as <br />measured by video and a) number of young squawfish and b) <br />number of backwaters utilized by young squawfish. <br />Extend sampling to other potential squawfish nursery <br />habitats (FY-3). <br />Determine relationships, if any, between habitats utilized <br />by young squawfish and physical and biological habitat <br />measurements (FY-4). <br />Compare intensive sampling data with standardized monitoring <br />data to verify and/or refine standardized sampling <br />techniques (FY-4). <br /> <br />VII. Study Schedule (start/end by: <br /> <br />Task 1: <br />Task 2: <br />Task 3: <br />Task 4: <br />Task 5: <br />Task 6: <br />Task 7: <br /> <br />FY92-94 - obtain video and field data <br />FY95 - report on relationship between habitat availability <br />(video) and habitat utilization by squawfish <br />FY96 - analyze habitat measurements in relation to squawfish <br />utilization to determine if we can identify <br />"quality" nursery habitat and whether these habitats <br />can be distinguished using video. Final report. <br />