Background
During the 1990s, approximately half of the existing populations of Pacific salmon and steelhead in the contiguous U.S. were listed as threatened or endangered under the federal Endangered Species Act. Anthropogenic change is believed to be at least partially responsible for many of these listings. Subsequently, considerable effort has been expended trying to quantify effects of what in the Pacific Northwest are commonly referred to as the "four Hs" (habitat, harvest, hatcheries, hydropower development) on survival, mortality, and population growth rate of listed salmon and steelhead. The implicit and widespread view is that anthropogenic change is primarily an ecological problem. However, virtually every anthropogenic change that affects these key ecological and demographic parameters will also have profound evolutionary consequences. Evolutionary responses to altered environments affect fitness and resilience, with attendant affects on long-term viability of populations. To date only the evolutionary consequences of artificial propagation, and recently those of size-selective harvest, have received much attention. This issue, however, is much more pervasive and is relevant to all anthropogenic activities. For example, consider the selective impact of the Columbia River hydropower development: selection for migration timing that maximizes survival through the current hydropower system rather than through a pristine river; selection on physiology and morphology for ability to migrate (as both juveniles and adults) through large reservoirs; selection for ability to find juvenile bypass openings or adult fish ladders; selection for the physiological capacity to survive in dramatically changed environments (temperature, flow regime, structural habitat) in the lower river and estuary; selection from invasive species (predators, competitors, disease vectors) in reservoirs; selection imposed by genetic and ecological interactions with large numbers of hatchery-propagated salmon and harvest regimes targeting these fish; etc.

More broadly, any anthropogenic activity that affects salmon and steelhead directly -- or that affects their environments -- has the potential to change selective regimes. Recent studies demonstrate remarkably fast responses of fish to novel selection patterns, so the concerns raised are not merely academic. We therefore expect that a broad array of anthropogenic factors will have already had - and will continue to have -- evolutionary impacts on salmon and steelhead populations. It is much less clear, however, what these changes mean for the long-term viability of natural populations in human-altered environments. Will they ameliorate the impacts of anthropogenic change, or will they potentially exacerbate them?

The Symposium
This is a large, complex topic that could form the basis of an extended research program in the future. As an initial effort, the NOAA Fisheries Northwest Fisheries Science Center will sponsor a Symposium that will bring together a) top regional scientists with detailed knowledge of salmon and the nature of anthropogenic changes to their environment; and b) top evolutionary biologists with expertise in evaluating responses of natural populations to altered selective regimes. The Symposium has two major objectives: 1) to provide a public forum for discussing these important issues and raising awareness of their importance for salmon conservation; and 2) to provide necessary information on salmon biology to evolutionary biologists and information on evolutionary biology to salmon biologists, in the hope of establishing substantive collaborations and exchanges. Click here for the Symposium Agenda, and click here to register. The symposium will be followed immediately by a catered reception and poster session. Click here if you are interested in contributing a poster.

Symposium: Dec 7
Program begins at 8:30 AM; poster session ends at 6:30 PM
Museum of History and Industry

Seattle's Museum of History & Industry (MOHAI)
McCurdy Park
2700 24th Ave East
Seattle, WA 98112-2099
Voice: 206-324-1126
Web: www.seattlehistory.org

Click here for a map.

The Symposium will be followed by a two-day workshop of invited participants who will focus in more detail on specific kinds of anthropogenic change faced by Pacific salmon and the kinds of evolutionary responses they can be expected to elicit. Each workgroup will include regional scientists familiar with datasets for Pacific salmon and steelhead as well as evolutionary biologists who have experience in interpreting such data in an evolutionary context. Workshop topics include:

Evolutionary consequences of size-selective harvest
Anthropogenic influences on salmon disease prevalence and resistance
Evolutionary responses of Pacific Northwest salmon to global climate change
Selective loss of habitat types and effects on life history diversity within and among populations
Evolutionary response to changes in water flow regimes and temperature patterns caused by hydropower operation
Habitat fragmentation and population structure
Snake River fall chinook salmon: a case study in evolutionary responses to multiple anthropogenic changes

Steering Committee
Jeff Hard, NOAA Fisheries, Seattle
Ray Huey, University of Washington
Joe Travis, Florida State University
Robin Waples, NOAA Fisheries, Seattle

Questions?
Regarding registration, contact Tara Torres (303-497-8694);
Regarding the Symposium program or poster session, contact Robin Waples.

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