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but for different reasons. The overall status of the razorback sucker is critical--no young razorbacks have been collected in the last 27 years and the number of adult fish has sharply declined. Existing information leads us to believe that the decline of the razorback sucker is related to reduced spring flows. Razorbacks are spring-spawners; water temperature and photoperiod initiate spawning activities. Razorbacks tend to seek off-channel, flooded lowland areas to spawn (where water temperatures are warmer earlier in the year). High spring flows are therefore needed both to flood these lowlands and to maintain the complexity of the channel which provides the off-channel habitats that these fish require. winter (November-Februarvl wintertime is, in general, a period of low activity for fish. Adult Colorado squawfish congregate in deep pools and low velocity runs. Razorbacks utilize pools, eddies and runs with a preference for deeper water than Colorado squawfish. The Division of Wildlife shares the belief of Service researchers that winter habitat for either species is not limiting their abundance at this time. Winter flows volumes have generally increased over time due to irrigation return flows. It has yet to be determined whether these higher winter flows have a beneficial or detrimental effect on the fishes. Ongoing research will refine the flow recommendations but the report tentatively, recommends no reduction in winter flows below historic rates in the 1,000-2,000 cfs range (the average winter flow is approximately 1,400 cfs). Transition months (October. Marchl In terms of habitat use, October is more similar to summer than to winter. The Service therefore recommended that recent flow regime or the previously recommended (and accepted) summer flows be maintained for October. March is truly a transition month. Squawfish are moving from pools where they have spent the winter, to runs. Razorbacks are still in their winter mode but their use of backwater areas starts to increase at this time. Water temperatures during March are increasing as are the activity levels of the fish. The Service's recommendation is to maintain the current March flow regime. This is an area where more information should be brought to bear on fine-tuning flow recommendations. CONCLUSIONS & RECOMMENDATIONS Sorinq (Aoril-Junel - Fiaure 5 o Maintain the current frequency (25%) of stateline peak flows in the 30,000-40,000 cfs range. 7