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MATERIALS AND METHODS In January 1989 a questionnaire was sent to the managers of the 34 fish hatcheries and 9 rearing ponds administered by ODFW. The questionnaire requested information on bird predators, fish losses, and the measures used to control predation. Additional questions were asked about funding and potential projects to control bird predation. A copy of the questionnaire is reprinted in Appendix A. Figure 1 shows the locations of ODFW fish rearing facilities on a map of Oregon. Responses to the questionnaire provided a database that catalogued control measures, species of bird predators, and numbers of fish lost. The database also included responses to a question about future plans to add control measures, and a question about suggestions for measures that could be taken if unlimited resources to control predation were available. A second questionnaire, sent out in May 1989, went to managers of all fish rearing facilities, liberation coordinators, and others who have first hand knowledge of predation at the hatchery and at release. This questionnaire, reproduced in Appendix B, requested estimates of costs to free ODFW fish rearing facilities from predators, past and present release strategies that avoid or reduce predation at release and after release, and rearing strategies that reduce vulnerability of fish to predation. The original database was rewritten to accommodate the new data obtained from the second questionnaire. A preliminary analysis of these data was provided for Harry Wagner, then chief of the Fish Division, in a briefing paper that described the predation problem at hatcheries and the ways to minimize the problem. An additional paper has been submitted to the 1991 Oregon legislature to fulfill the requirements for HB 2735. RESULTS AND DISCUSSION Predators The seventeen avian predators reported from Oregon fish rearing facilities are shown in Table 2. The most common avian predator observed was the heron, which was observed at 35 of the 43 facilities questioned. The great blue heron and the green heron combined probably account for most of the losses statewide. Belted kingfishers were observed at 30 stations, but their small size keeps them from preying on the largest fish. 2