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our fishery technicians, subjected themselves to long work days and physically trying weather conditions. Kendall Jackson provided additional field assistance when called upon. David Statler provided valuable technical assistance and reviewed manuscripts. John Knutzen, Scott Wilcox, and Ken Winnick assisted during the collection of hydraulic crosssection data and Lisa Russel summarized and entered these data into data base format. Vance Penton assisted in designing and fabricating our freeze-core equipment. Greg Delwitch, Jeff Hanson, Ed Kim, and Mark Lindgren of the U.S. Army Corps of Engineers coordinated controlled dam flows, which were essential to our study. Numerous employees of the U.S. Geological Survey transferred gaging station data to our project personnel. Bill Miller, Travis Coley, and Ralph Roseberg of the U.S. Fish and Wildlife Service, Idaho Fishery Resource Office furnished equipment and were always available for technical questions. Ed Buettner and Lance Nelson of the Idaho Department of Fish and Game assisted in PIT-tagging and Jeff Earhart provided computer uploading assistance. Judy Cress of the Pacific States Marine Fisheries Commission provided computer training and assistance in retrieving PIT tag information. The U.S. Forest Service provided substrate sieves and other equipment when needed. Meetings were held for purposes of peer review and interagency coordination.

This review summarizes what is known about the influence of water temperature and velocity on the migration and spawning success of an inland population of Chinook salmon Oncorhynchus tshawytscha. Models are then developed and used to illustrate how migration and spawning success might change if temperatures and velocities increase under a future climate. The illustration shows the potential for moderate increases in temperature and velocity to reduce homing and increase energy expenditure. Those two outcomes would reduce the abundance, productivity, and diversity of the population studied. Under the future scenario illustrated, it would become difficult for fish management actions alone to recover conservation-reliant populations of inland Chinook salmon.

Evaluations of human impacts on Earth's ecosystems often ignore evolutionary changes in response to altered selective regimes. Freshwater habitats for Snake River fall Chinook salmon (SRFCS), a threatened species in the US, have been dramatically changed by hydropower development and other watershed modifications. Associated biological changes include a shift in juvenile life history: Historically essentially 100% of juveniles migrated to sea as subyearlings, but a substantial fraction have migrated as yearlings in recent years. In contemplating future management actions for this species should major Snake River dams ever be removed (as many have proposed), it will be important to understand whether evolution is at least partially responsible for this life‐history change. We hypothesized that if this trait is genetically based, parents who migrated to sea as subyearlings should produce faster‐growing offspring that would be more likely to reach a size threshold to migrate to sea in their first year. We tested this with phenotypic data for over 2,600 juvenile SRFCS that were genetically matched to parents of hatchery and natural origin. Three lines of evidence supported our hypothesis: (i) the animal model estimated substantial heritability for juvenile growth rate for three consecutive cohorts; (ii) linear modeling showed an association between juvenile life history of parents and offspring growth rate; and (iii) faster‐growing juveniles migrated at greater speeds, as expected if they were more likely to be heading to sea. Surprisingly, we also found that parents reared a full year in a hatchery produced the fastest growing offspring of all—apparently an example of cross‐generational plasticity associated with artificial propagation. We suggest that SRFCS is an example of a potentially large class of species that can be considered to be “anthro‐evolutionary”—signifying those whose evolutionary trajectories have been profoundly shaped by altered selective regimes in human‐dominated landscapes.

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