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XI. Conservation Recommendations Section 7(a)(1) of the ESA directs Federal agencies to utilize their authorities to further the purposes of the ESA by carrying out conservation programs for the benefit of threatened and endangered species. Conservation recommendations are discretionary measures suggested to minimize or avoid adverse effects of a proposed action on listed species or critical habitat, or to develop additional information. NMFS believes the following conservation recommendations are consistent with these obligations, and therefore should be implemented by NMFS. 1.NMFS should develop better estimates of the ocean distribution and fishery impacts on listed Snake River spring/summer chinook. Very little is known about the ocean distribution or fishery impacts of Snake River spring/summer chinook, primarily because so few tags of the hatchery indicator stocks have been recovered. At this point, it is not possible to determine whether this is due to the very low survival rates of the tagged fish or that the fish are, in fact, not susceptible to ocean fisheries. Prior to the1996 season, the PFMC should update the analysis of CWT recoveries and seek alternatives to improve available information regarding the ocean distribution and harvest impacts of spring/summer chinook. 2.NMFS should continue to tag representative groups of fall chinook from the Lyons Ferry Hatchery and upriver bright fall chinook. Tagging of sub-yearling Lyons Ferry chinook will contribute to improved estimates of the impacts of fisheries on listed fall chinook. Tagging of the upriver brights is necessary to facilitate comparative analysis of harvest rates, particularly in the Columbia River fisheries. 3.NMFS should assess whether Lyons Ferry Hatchery stock adequately represents the distribution of Snake River natural fall chinook. There is a general question about how well tagged hatchery fish represent their natural stock counterparts. It is reasonable to question whether Lyons Ferry Hatchery fish adequately represent the distribution of natural Snake River fall chinook. The responsible agencies should consider the merits of tagging listed fish to assess whether the hatchery and natural stocks have similar distributions. An alternative would be a more thorough analysis of other hatchery/natural stock groups that are presumed to have similar distributions. 4.NMFS should develop better estimates of the ocean distribution and fishery impacts on sub-legal chinook. There is even less information on the distribution and fishery impacts on sub-legal chinook. This is a problem common to most fisheries and most stocks coast-wide. NMFS and other appropriate agencies should seek alternatives for developing the necessary information. 5.NMFS should develop a measure of adult mortality and escapement that permits direct comparison of ocean and inriver harvest mortality and interdam loss for listed Snake River salmon. One of NMFS' long term objectives for Snake River listed salmon is to develop estimates of adult-equivalent human-induced mortality for all actions. A new method for estimating fishery exploitation rates that will relate ocean and inriver harvest is underdevelopment and should help provide a consistent basis for accounting of the fate of fish that survive to ocean recruitment. Work on these kinds of accounting tools should continue. 6.NMFS should assess the feasibility of using genetic Mixed Stock Analysis to improve estimates of harvest rate on Sacramento River winter-run chinook salmon. Alternative methods of monitoring harvest on winter-run chinook may be feasible through Genetic Stock Identification (GSI) (Brodziak et al. 1992). Genetics research is underway to distinguish various Central Valley chinook salmon stocks in the Bay-Delta, and results preliminarily suggest the potential to distinguish winter-run chinook from the other runs using a GSI (Banks et al. 1994; D. Hedgecock, pers. comm). Because salmon populations tend to show fewer genetic differences within the same watershed, and greater differences between watersheds, it is probable that winter-run chinook could be genetically distinguished from other Central Valley and coastal chinook salmon stocks in the ocean. This technique may present a more accurate method of measuring harvest and should be explored. 7.NMFS should develop a life cycle model for the Sacramento River winter-run chinook salmon. A comprehensive life cycle is essential for evaluating the present management strategies, as well as alternative management strategies, in order to quantitatively determine the likelihood of survival and recovery of winter-run chinook over the long-term.
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