Translocations to recover native fishes have resulted in mixed success. One reason for the failure of these actions is inadequate assessments of their feasibility prior to implementation. Here, we provide a framework developed to assess the feasibility of one type of translocation—reintroduction. The framework was founded on two simple components of feasibility: the potential for recipient habitats to support a reintroduction and the potential of available donor populations to support a reintroduction. Within each component, we developed a series of key questions. The final assessment was based on a scoring system that incorporated consideration of uncertainty in available information. The result was a simple yet transparent system for assessing reintroduction feasibility that can be rapidly applied in practice. We applied this assessment framework to the potential reintroduction of threatened bull trout Salvelinus confluentus into the Clackamas River, Oregon. In this case, the assessment suggested that the degree of feasibility for reintroduction was high based on the potential of recipient habitats and available donor populations. The assessment did not provide a comprehensive treatment of all possible factors that would drive an actual decision to implement a reintroduction, but it did provide a fundamental level of feasibility assessment that is often lacking in practice. Received May 28, 2010; accepted December 22, 2010

The bull trout Salvelinus confluentus is an apex predator in native fish communities in the western USA and is listed as threatened under the U.S. Endangered Species Act (ESA). Restoration of this species has raised concerns over its potential predatory impacts on native fish fauna. We held a five-person expert panel to help determine potential impacts of reintroducing bull trout into the Clackamas River, northwest Oregon, on the viability of four anadromous salmonid populations that are listed as threatened under the ESA: spring and fall Chinook salmon Oncorhynchus tshawytscha, coho salmon O. kisutch, and winter steelhead O. mykiss. The panel session was rigorously structured and used a modified Delphi process with structured expert elicitation, disclosure, discussion, and brainstorming. Each panelist distributed 100 score points among seven categories of potential bull trout impact (from no impact to very high impact) on extinction probabilities for the anadromous salmonids. Results were provided by individual panelists rather than as a group consensus and were summarized as means and variations in scores to express the panelists' individual uncertainty, variability among the panelists, and expected differences among the affected salmonids. Score results suggested that panelists viewed the potential impact of bull trout as very low or moderately low for spring Chinook salmon, coho salmon, and winter steelhead and mostly none to very low for fall Chinook salmon. Panelists also provided 19 possible monitoring activities and 21 possible management actions for assessing potential impacts and taking remedial action if bull trout are found to have unacceptable adverse effects. Results of the panel were used by the U.S. Fish and Wildlife Service to help craft and execute a plan to reintroduce bull trout into the Clackamas River system under the ESA. This rigorous expert panel process can be used for a wide range of evaluations in situations where empirical data are sparse or ecological interactions are too complex for explicit analytic solution.

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Foskett Spring is a small isolated desert spring in the Warner Basin of Oregon containing an undescribed subspecies of speckled dace protected under the US Endangered Species Act. Uncertainty regarding the taxonomic status of Foskett dace has raised questions about their evolutionary relationship to other more abundant populations in the Warner Basin. To address these questions, we sequenced 1,982 base pairs (bp) of the ND2 and cyt-b genes of mitochondrial DNA (mtDNA) for 85 fish from Foskett Spring, the surrounding Warner Basin, and the adjacent Goose Lake Basin. We observed 58 unique mtDNA haplotypes defined by 96 bp substitutions in both genes. MtDNA sequences were highly divergent and reciprocally monophyletic between dace from the Warner and Goose Lake Basins, with sequence divergences (5 and 3% at ND2 and cyt-b, respectively) in the range usually observed between fish species. In contrast, mean sequence divergence between Foskett dace and other Warner Basin populations was less than 1%, with no evidence of reciprocal monophyly among mtDNA lineages. These results indicate that Foskett dace and other populations in the Warner Basin are approximately equally diverged from one another evolutionarily, suggesting similar times of divergence since the late Pleistocene. We believe further studies are needed to determine if rapid evolution of novel traits have occurred in dace inhabiting the unique ecological setting of Foskett Spring during the past 10,000 years.

Objective To evaluate the vulnerability of Bull Trout Salvelinus confluentus to potential climate changes across its range in Oregon, we compiled disparate expert knowledge of the distribution of spawning and rearing and combined these probabilistic statements as data along with documented records of breeding and rearing in a joint occupancy model. Methods The joint expert knowledge–occupancy model, which was based on discrete patches of cold water (≤13°C) suitable for spawning and rearing, permitted the association of true occupancy with climate and other explanatory variables while accounting for variation in detection probability. We then applied estimated relationships of patch occupancy with explanatory variables to projected coldwater patch configurations in the years 2040 and 2080. Result Projections of the kilometers of occupied coldwater patch in future decades suggest precipitous declines if current relationships of occupancy with environmental variables are maintained. Impacts of climate changes in future decades manifest directly through the outright loss of coldwater patches and increases in winter high flows but also indirectly by increased isolation. Conclusion Combining probabilistic statements of species distributions from knowledgeable experts with sparse occupancy data may be a robust and timely alternative when large numbers of repeated occupancy surveys are infeasible.