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DRAFTS process that formed them (appendix, Table A). Furthermore, the development of each habitat is related to fluctuating flow levels and can be divided into three stages: areas with some flow (small side channels and shoreline areas), areas with no flowing water and one end open to the main channel (backwaters), and areas with no access to the main channel (isolated pools). We collected fish from each habitat using a 1.2m by 4m seine, with 1.6mm mesh size. The number of seine hauls varied from one to three with the size of the habitat. Tn general, habitats wider than 4m but less than 25 meters long were seined once, those between 25 and SOm seined twice, and those > SOm seined three times. In large habitats, the seine hauls were usually made at the transects. Habitats less than 4m wide and 25m long were completely seined in one pass. Native fish were identified, measured and released in the field. Colorado squawfish mortalities,were preserved in ethanol during the first two years of the study, and were transferred to the Larval Fish Laboratory at Colorado State University (CSU) for future analysis of scales and otoliths. Non-native fishes were identified and separated into adult/subadult categories in the field, or were preserved for later identification and enumeration. Geometric mean catch-per-effort (CPF~ in #fish/100m2 and #fish/100m3 was calculated per trip from all YOY squawfish CS collected, divided by the area and volume sampled in all seine hauls. ~ ~ ~ ~~ ~~~ ~~,~ w6 ~ ~ ~ Results ~pJ/ r Species composition and relative abundance A total of 17 different species were collected during the study period (species list, appendix, Table B). Five species were native, the remainder were non-native. The most common species collected were non-native cyprinids (NNC); the red shiner (Cyprinella lutrensis), sand shiner (Notropis stramineous) and fathead minnow (Pimephales promelas). These 3 species -5-