Elwha Watershed Information Resource

Telemetry is being used in the Elwha River Restoration Project to learn more about the fish in the river, so that restoration efforts can be designed effectively. Telemetry is the process whereby data can be sent remotely (for instance, from a radio or acoustic tag) to allow researchers to monitor the activities of animals that are not easily visible (such as fish). This method provides more data than other tradition techniques (such as mark and recapture). For example, if specialized tags are used, it is possible to determine a fish’s depth and temperature.

Data from tagged animals provides specific information on:

• Habitat use (location and physical habitat characteristics);

• Migration timing, rates, and distances; and

• Diurnal activity.

Researcher examining tagged salmon carcasses. National Park Service/USGS-BRD

In order to guide the recovery of the Elwha watershed after dam removal, it is important to understand the current distribution of fish populations below the Elwha dam and their use of this area before, during, and after dam removal. The pre dam removal research will provide managers with critical information--such as when to control sediment releases during dam removal based on information about when fish are migrating. Based on pre dam removal studies of fish habitat use, mangers will be able to determine if fish habitats were altered or destroyed during the removal process.

Since 2005, three major pre dam removal studies have been undertaken. In the sections below, these tagging and telemetry efforts are discussed.

Early migratory behavior of Elwha River juvenile salmon and steelhead

Between April and June of 2006, 87 outmigrating Chinook (Oncorhynchus tshawytscha), coho (O. kistuch), and steelhead (O. mykiss) smolts were surgically implanted with acoustic transmitters (Vemco R4K) and released back into the Elwha River to continue their migration out to the ocean. Tagging of salmon and steelhead was done opportunistically in proportion to the observed runs. Both hatchery and wild origin stocks were tagged. The primary objective was to determine patterns of estuary and nearshore habitat usage and residence time for juvenile salmon of Elwha River origin.

Juvenile salmon were monitored using six fixed-site receivers deployed between the western edge of Freshwater Bay and Morse Creek, Washington. An additional two receivers were deployed within Dungeness Bay, Washington, about 20 miles from the mouth of the Elwha River.

All acoustic tags used in this study were compatible with the Pacific Ocean Shelf Tracking (POST) project, a network of acoustic receivers deployed along the west coast of North America. Data from POST listening lines across the Strait of Juan de Fuca, in the Puget Sound, and in the Strait of Georgia will be used to map further movements of Elwha River origin juvenile salmon in the marine environment.

Collaborators:

• Chuck Boggs, University of Idaho

• Mike McHenry, Lower Elwha Klallam Tribe

• Raymond Moses, Lower Elwha Klallam Tribe

• Chris Peery, University of Idaho

• Larry Ward, Lower Elwha Klallam Tribe

• Nancy Wright, University of Idaho

Use of radiotelemetry to determine migratory patterns of bull trout in the Elwha River before dam removal: Implications for recovery of a threatened species

Federally threatened populations of bull trout (Salvelinus confluentus) are known to inhabit the lower, middle, and upper sections of the Elwha River. These three populations of bull trout have been reproductively isolated by the dams for more than 90 years. Little information is known about bull trout biology and migratory patterns. Yet, in order for Elwha River bull trout conservation and recovery efforts to be successful after the dams are removed, a more complete understanding of life history and migratory patterns prior to dam removal is a prerequisite.

In 2005, the National Park Service implemented a radiotelemetry study to characterize movements, life histories, and genetic composition of bull trout prior to dam removal. Results from this study will be used to establish baseline conditions necessary to evaluate future recolonization and determine whether bull trout resume anadromy. Restoration of bull trout in the Elwha River after dam removal is a high priority for the Olympic National Park and the U.S. Fish and Wildlife Service because it provides an opportunity to reestablish forms of this species in the park with anadromous and fluvial life history forms.

The removal of the two dams and restoration of ecosystem processes also represents an unprecedented opportunity to understand pre and post dam removal effects on bull trout that inhabit the middle and upper portions of the river--including the rate and extent of recolonization by bull trout from the lower river. Olympic National Park contains some of the last remaining undisturbed habitat throughout the entire range (migration) of the species.

Specific objectives include studying bull trout in order to:

• Characterize spatial and temporal movements of adults and juveniles;
  
• Determine spawning time and location;
• Determine extent of tributary use;
• Determine potential barriers to migration; and
• Characterize genetic structure of populations that inhabit the middle and upper river and determine whether there is evidence of hybridization with brook trout.

By October 2006, 28 juvenile and 65 adult bull trout were radio-tagged and their movements are being tracked using manual, aerial, and fixed-site telemetry methods. During the tagging process, a tissue sample was collected from each bull trout for genetic analysis. This project is scheduled to be completed in August 2007.

Collaborators:

• Sam Brenkman, Olympic National Park
• Steve Corbett, Olympic National Park
• Patrick Crain, Olympic National Park

Radio-tagging adult coho salmon in the Elwha River

In order to track the movement and behavior of coho (Oncorhynchus kistuch) salmon in relation to their habitat, NOAA scientists worked with tribal commercial fisherman to tag 14 adult coho salmon in 2005. They caught the salmon in the Elwha River (river mile 1.5) and tagged them with external radio transmitters. Fish movements were monitored by four fixed receiver sites (between river mile 1.5 and the Elwha Dam) and by mobile tracking on foot.

Research goals:

• Relate fish movement and behavior to habitat types within the river.
• Examine whether hatchery fish and wild fish are equally likely to recolonize the middle and upper reaches of the Elwha River once those habitats become accessible.

Collaborators:

• Brian Burke, NOAA Northwest Fisheries Science Center
• Kinsey Frick, NOAA Northwest Fisheries Science Center
  
• Lower Elwha Klallam Tribe
• Olympic National Park

Additional Information

Brenkman, S. J., and S. C. Corbett. 2005. "Extent of anadromy in bull trout and implications for conservation of a threatened species." North American Journal of Fisheries Management. Volume 25. Pages 1073 to 1081.

Brenkman, S. J., S. C. Corbett, and E. C. Volk. 2007. "Use of otolith chemistry and radiotelemetry to determine age-specific migratory patterns of anadromous bull trout in the Hoh River, Washington." Transactions of the American Fisheries Society. Volume 136. Pages 1 to 11.

Brenkman, S. J., G. L. Larson, and R. E. Gresswell. 2001. "Spawning migration of lacustrine-adfluvial bull trout in a natural area." Transactions of the American Fisheries Society. Volume 130. Pages 981 to 987.

Winter, J. 1996. "Advances in underwater biotelemetry." Pages 555-590 in B. R. Murphy and D. W. Willis, editors. Fisheries Techniques, 2nd Edition. American Fisheries Society, Bethesda. Maryland.

Wunderlich, R. C., B. D. Winter, and J. H. Meyer. 1994. "Restoration of the Elwha River Ecosystem." Fisheries. Volume 19. Pages 11 to 19.