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September 13, 2011
Paul Laustsen 650-454-7264 plaustsen@usgs.gov

Elwha River Restoration Science Explained at Science Symposium

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PORT ANGELES, Wash. — Wading through abstracts can be daunting, so in this USGS media tip sheet, we have done the work for you. Selected and compressed for your convenience, here is the Elwha River science that the USGS has been working on, often as part of an interagency collabora­tion. The topics are presented in chronological order with session in­formation. USGS scientists involved are listed. Complete listings can be found in the symposium program. As a reminder: all of these events are open to the public. 

News media representatives are invited to visit the Elwha Science Symposium media room at Peninsula College in Port Angeles, Wash, in room M227. Staff there will help you connect with USGS scientists and other experts. 

Oral Sessions (some also are poster sessions) 

OVERVIEW OF ELWHA HYDROLOGY AND ITS ROLE IN ECOSYSTEM RESTORATION
Christopher P. Konrad, USGS Washington Water Science Center, Tacoma, Wash.
Oral session 1B; Thursday, 10:40 a.m., Science Building Lecture Hall
A century of observation affords a good picture of the Elwha River’s hydrology. The river has ample capacity to transport sediments deposited in the reservoirs, provided it can access these deposits once the dams are removed. Channel cutting and migration will isolate some sediments, leaving terraces. The river will routinely transport and deposit more sediment in the channel once the dams are gone, restoring a fundamental ecological process.

ASSESSING SALMONIDS AT A FLOATING WEIR TO YIELD DATA FOR RECOVERY
Jeff J. Duda, USGS Western Fisheries Research Center, Seattle, Wash.
Oral session 1A; Thursday, 11:20 a.m., Little Theater (PUB)
Understanding the response of fish populations to dam removal is a priority. An interagency team of scientists installed an innovative weir to collect information about the types of fish present and their population characteristics. Chinook, pink, coho, sockeye, and chum salmon, plus steelhead, bull trout, and coastal cutthroat trout were captured and described in the first two weeks of the weir’s operation. The 2011 sampling began in August.

MONITORING OF SUSPENDED-SEDIMENT LOAD IN THE LOWER ELWHA DURING THE FIRST TWO YEARS OF DAM REMOVAL
Christopher S. Magirl, Christopher A. Curran, Christiana R. Czuba, and Mathieu D. Marineau, USGS Washington Water Science Center, Tacoma, Wash.
Oral session 1B; Thursday, 11:40 a.m., Science Building Lecture Hall
Biological and physical systems in the Elwha could be influenced by sediments that move downstream. Turbidity, a measure of suspended sediments, is monitored continuously downstream of the Elwha Dam using several sophisticated instruments installed by the USGS and collaborators. A variety of data are being analyzed to establish a continuous record of suspended-sediment load carried by the lower Elwha River during and after dam removal.

ELWHA AQUATIC FOODWEB RESEARCH: BASELINE, EXPERIMENTAL, AND FUTURE DATASETS
Jeff Duda, USGS Western Fisheries Research Center, Seattle, Wash.
Oral session 2A; Thursday, 1 p.m., Little Theater (PUB)
Data collected across the Elwha basin show biomass of periphyton (small plants and animals attached to submerged surfaces) consistently higher in regulated sections, and benthic invertebrate composition at sites above the dams distinct from sites between and below. Nutrient limitation and salmon carcass addition show periphyton growth rates and heavy-nitrogen-isotope ratios of juvenile salmon significantly elevated in treatment reaches over reference reaches. These and additional data are part of a monitoring program to understand how fish colonization will affect the food web.

THE ELWHA RIVER ESTUARY: AN OVERVIEW OF ITS MORPHOLOGY AND HYDROLOGY
Jonathan Warrick, USGS Pacific Coastal and Marine Science Center, Santa Cruz, Calif.
Oral session 2B; Thursday, 1 p.m., Science Building Lecture Hall
At the Elwha River’s mouth, freshwater mixes with the saline Strait of Juan de Fuca. Data collected by the USGS and Lower Elwha Klallam Tribe reveal patterns of water mixing in the estuary. Changes in the morphology of the river mouth alter the water exchange throughout the estuary. An exceptional river discharge in 2007 resulted in major shifting in the channel at the river mouth, leading to more exchange of fresh and saline water in one portion of the estuary.

THE ELWHA DELTA: SHRINKING OR GROWING?
Jon Warrick, USGS Pacific Coastal and Marine Science Center, Santa Cruz, Calif.; Andrew Stevens, and Guy Gelfenbaum, USGS Pacific Coastal and Marine Science Center, Menlo Park, Calif.
Oral session 2B; Thursday, 1:20 p.m., Science Building Lecture Hall
Analysis of topography and bathymetry data collected annually collected on the beach and in the near-coastal zone suggests that the Elwha typically delivers more sediment to the coastal zone than is transported away from the river mouth, that sediment is retained in the river-mouth bar, and that accretion is primarily sub-tidal. These results suggest that accretion occurs in the vicinity of the river mouth while adjacent beaches and subtidal areas erode.

RIPARIAN MAMMAL AND AMPHIBIAN COMMUNITIES PRIOR TO DAM REMOVAL AND ECOSYSTEM RESTORATION
Kurt Jenkins, Nathan Chelgren,  Michael Adams, Steven Perakis, USGS Forest and Rangeland Ecosystem Science Center,  Port Angeles, Wash.
Oral session 2A; Thursday, 2 p.m., Little Theater (PUB)
Mammals and amphibians are part of the food web that could change after dam removal. A multispecies monitoring program was devised to document current and future patterns in species occupancy, community composition, and species richness of mammal and amphibian communities in the Elwha riparian area. Preliminary information about possible changes in species distributions following river restoration will be presented.

POTENTIAL EFFECTS OF DAM REMOVAL ON COASTAL TURBIDITY AND SEDIMENTATION
Guy Gelfenbaum, Jonathan Warrick, and Andrew Stevens; USGS Pacific Coastal and Marine Science Center, Santa Cruz, Calif.
Oral session 2B; Thursday, 2 p.m. Science Building Lecture Hall
Poster 12; Thursday, 4:30 - 6:30 p.m., Sciences Building
To track the fate of sediments in coastal waters, the USGS combined observations of the currents, waves, and the buoyant river plume of the Elwha with modeling of the characteristics of the region’s water movement. Scientists predict that fine sediment discharged toward the east of the river mouth should stay in suspension or move frequently, due to strong currents there. Sediment discharged toward the west is more likely to accumulate on the seafloor because of relatively weak currents between the river mouth and Freshwater Bay. These predictions will be tested during and after dam removal.

IMPORTANCE OF FLOODPLAIN CHANNELS IN THE ELWHA DAM REMOVAL
Jeff Duda, USGS Western Fisheries Research Center, Seattle, Wash.
Oral session 3B; Thursday, 2:40 p.m., Science Building Lecture Hall
Scientists anticipate that floodplain channels will dampen negative effects of sediment deposits and provide biological refuges after dam removal. Federal, state and tribal scientists have collaborated to identify the key questions and develop adequate study designs to understand how salmon will react to the sediment release in combination with the availability use of a large amount of pristine habitat that will become available for occupancy.

STRUCTURE, COMPOSITION, AND DIVERSITY OF FLOODPLAIN VEGETATION
Patrick B. Shafroth, USGS Fort Collins Science Center, Fort Collins, Colo.
Oral session 3C; Thursday, 2:40 p.m., Conference Hall (PUB)
Floodplain vegetation changes and diversity in the Pacific Northwest are linked to water flow, fluxes of sediment, and large wood, factors that will change with dam removal. The USGS and collaborators collected baseline data to predict the responses of vegetation to dam removal. Along 15 cross-valley transects above, between, and downstream of both dams, they documented the composition, structure, age, and diversity of vegetation and the associated environment.

REVEGETATING THE NEWLY EXPOSED LAND BEHIND THE DAMS
Patrick B. Shafroth, USGS Fort Collins Science Center, Fort Collins, Colo.
Oral session 3C; poster 19; Thursday, 3 p.m., Conference Room (PUB)
Dam removal offers the opportunity to test revegetation methods derived from modern understanding of plant succession. Native grasses will be seeded on the sediments. Fleshy-fruited species will be planted to attract seed-scattering birds. Fast-growing, early seral woody species will be selected based on local growing trials, and woody debris along dewatered shorelines will be redistributed to protect seedlings.

CHANNEL EVOLUTION ON THE DAMMED ELWHA RIVER, 1939-2010
Amy E. Draut, Joshua B. Logan, and Mark C. Mastin, USGS Pacific Coastal and Marine Science Center, Santa Cruz, Calif.
Oral session 3B; Thursday, 3 p.m., Science Building Lecture Hall
Poster 17; Thursday, 4:30 - 6:30 p.m., Sciences Building
The USGS has conducted a comprehensive field and aerial photographic analysis of dam influence on the Elwha River. The analysis defines how the dams’ presence has caused spatial variations in the sedimentary and geomorphic characteristics of the lower Elwha River channel. It establishes the baseline for evaluating channel response to the restoration of the upstream sediment supply.

DAMS’ INFLUENCE ON FLOODPLAIN DYNAMICS AND GRAIN SIZE DISTRIBUTIONS
Jeff Duda, USGS Western Fisheries Science Center, Seattle, Wash.
Oral session 3B; Thursday, 3:40 p.m., Science Building Lecture Hall
The percentage of floodplain surfaces more than 75 years old increases below the dams and fluctuates greatly above them. Channel bed particles are much coarser immediately downstream, but decrease rapidly with distance from the dams. Fine sediment released by the dams’ removal should cause considerable pool filling for a few years, but eventual recovery of natural sediment supply should widen channels, increase lateral channel migration and erosion of floodplain surfaces, and gradually shift floodplain age distributions.

SCUBA SURVEYS TO ASSESS EFFECTS OF DAM REMOVAL ON SHALLOW, SUBTIDAL BENTHIC COMMUNITIES
Steve Rubin,  Reg Reisenbichler, Rusty Rodriguez, Jeff Duda,  USGS Western Fisheries Research Center, Seattle, Wash.
Oral session 3A; Thursday, 3:40 p.m., Little Theater (PUB)
Scuba surveys were used to characterize biological communities in several nearshore marine habitats that could be influenced by new sediment additions. Kelp density was low in sandy areas, intermediate on gravel-cobble substrates, and highest on bedrock or boulder reefs. On average, 59 percent more kelp, invertebrate, and fish species occurred where boulders were present. The presence of boulders allowed species adapted to rocky reefs to coexist with species that inhabit sand and gravel-cobble substrates, thereby increasing species richness.

PREDICTING INVASIVE PLANTS’ SPREAD INTO THE DEWATERED RESERVOIRS
Andrea Woodward, Christian Torgersen, USGS Forest and Rangeland Ecosystem Science Center, Seattle, Wash.
Oral session 3C; Thursday, 3:40 p.m., Conference Room, (PUB)
The potential for exotic invasive plants to move onto land exposed by dam removal is high. The USGS and collaborators used data about the spatial distribution of invasive species and their vectors, coupled with information about the environment, to locate high-priority areas to treat prior to dam removal, as well as areas outside the park that require collaboration to minimize the spread of invasive species.

Poster Presentations

METHODS USED TO MONITOR CHANGES IN ELWHA NEARSHORE COMMUNITIES
Nancy Elder, USGS Marrowstone Marine Station, Nordland, Wash.; Steve Rubin, Reg Reisenbichler, and Jeff Duda, USGS Western Fisheries Research Center, Seattle, Wash.
Poster 8; Thursday, 4:30 - 6:30 p.m., Sciences Building
Marine habitats will be affected when sediments that have accumulated behind the dams are transported to the Strait of Juan de Fuca. For a baseline, scuba divers counted bottom-dwelling algae, invertebrates, and fish in fixed-width swaths to estimate their density. Data at uniformly spaced points were collected to estimate percent cover of encrusting or colonial species, as well as sea-floor attributes, such as sediment grain size, substrate composition, and seafloor relief.

COARSE SEDIMENT MOVEMENT ON THE MIXED-GRAINS-SIZE BEACH OF THE ELWHA DELTA
Jonathan Warrick, USGS Pacific Coastal and Marine Science Center, Santa Cruz, Calif.
Poster 11; Thursday, 4:30 - 6:30 p.m., Sciences Building
An application of technology that uses radio waves to transfer data from an electronic tag was used to track movement of coarse sediments on the delta of the Elwha River. Small rocks (clasts) were tagged, released, and monitored. The distance the clasts moved varied from less than 1 m to more than 500 m. Clast movements were paired with sediment characteristics across samples to evaluate the role of the angle of breaking waves on sediment movement on the beach.

THE COASTAL RIVER PLUME OF THE ELWHA
Jonathan Warrick and Andrew Stevens; USGS Pacific Coastal and Marine Science Center, Santa Cruz, Calif.
Poster 13; Thursday, 4:30 - 6:30 p.m., Sciences Building
Because of the transient eddies and the location of the Elwha mouth on the headland, flow immediately offshore of the river mouth is directed eastward twice as frequently as westward, resulting in a buoyant plume much more frequently “bent over” toward the east than the west. During these conditions, scientists believe that significant convergence of river plume water toward the frontal boundary will occur within 1 km of the river mouth. These results should help in understanding initial coastal sediment dispersal pathways during the dam removal project.

CARBON AND NITROGEN STABLE ISOTOPES IN ELWHA AQUATIC FOOD WEBS
Jeffrey J. Duda, USGS Western Fisheries Science Center, Seattle, Wash.
Poster 20; Thursday, 4:30 - 6:30 p.m., Sciences Building
Different chemical forms of an element, called stable isotopes, can be used to document the movement and magnitude of marine-derived nutrients derived from spawning salmon and their carcasses. Scientists report on stable isotope ratios in tissues of invertebrates and fish in sites throughout the Elwha River, as well as experimentally before, during, and after adding salmon carcasses to side channels between the dams and downstream.

THERMAL REGIMES AND THE DISTRIBUTION AND ABUNDANCE OF NATIVE BULL TROUT AND NON-NATIVE BROOK TROUT

Jason Dunham, Steven Clark, David Hockman-Wert, Nathan Chelgren, Michael Heck, and Robert Hoffman; USGS Forest and Rangeland Ecosystem Science Center, Corvallis, Ore.
Poster 21; Thursday, 4:30 - 6:30 p.m., Sciences Building
Scientists monitored presence and abundance of native, threatened bull trout and nonnative brook trout in the Elwha River. They repeatedly sampled 59 varied sites to estimate numbers and other characteristics of these fish. The relationship between floodplain habitats and thermal sensitivity, and influence of temperature on fish has helped understand bull trout and nonnative brook trout in the system and set the stage for future evaluations of how the river, its thermal regime, and its fish fauna may respond to dam removal.

OTOLITH ANALYSIS OF CHINOOK SALMON IN THE ELWHA
Karl Stenberg, Kim Larsen,  and Jeff Duda, USGS Western Fisheries Research Center, Seattle, Wash.
Poster 23; Thursday, 4:30 - 6:30 p.m., Sciences Building
Estuaries are important transition areas for young fall Chinook salmon as they migrate from freshwater rearing areas to the ocean. Otolith microstructure reveals that on average, the Chinook captured in the nearshore lived in the estuary for 25 days. Based on two years of data collected during juvenile migration towards the sea, wild fish mostly used the lower estuary, whereas hatchery fish mostly used the nearshore. Seventy-six percent of adult Chinook collected from the lower Elwha River in 2008 and 96 percent in 2009 were identified as hatchery fish.

IMPACT OF RESTORATION ON RIVER OTTERS AND AMERICAN DIPPERS
Kurt Jenkins, USGS Forest and Rangeland Ecosystem Science Center, Port Angeles, Wash.
Poster 25; Thursday, 4:30 - 6:30 p.m., Sciences Building
Scientists from multiple agencies are studying river otters and American dippers to document their distribution, seasonal movement patterns, and intake of marine-derived nutrients. They are capturing them below, between, and above the dams, attaching radio-tracking devices and collecting biological samples for stable isotope analysis. Restoring salmon to the Elwha should substantially alter its nutrient composition, and because otters and dippers are dependent on the river environment, they could be good indicators of restoration.

MOVEMENT AND HABITAT OF ELWHA’S BLACK BEARS
Kurt Jenkins, USGS Forest and Rangeland Ecosystem Science Center, Port Angeles, Wash.
Poster 26; Thursday, 4:30 - 6:30 p.m., Sciences Building
The restoration of native salmonids could provide a rich resource for black bears in autumn prior to denning. The USGS and collaborators equipped 18 black bears with tracking devices to collect information about movement patterns. They also used hair snares and DNA analysis to estimate the number and the sex of bears using riparian areas. Preliminary predictions of potential changes in use of the Elwha Valley by bears are presented.

VARIATION IN PLANT-SPECIES RICHNESS ALONG THE ELWHA: EFFECTS OF DAMS AND RECENT FLOODING
Patrick B. Shafroth, USGS Fort Collins Science Center, Fort Collins, Colo.
Poster 28; Thursday, 4:30 - 6:30 p.m., Sciences Building
Plant diversity depends on seed transport, sediment supply, flow, and disturbance patterns. University and USGS scientists studied how the two dams and a 2010 flood event altered plant diversity. On transects, they noted each vascular plant species and the percent cover, ground cover, sediment size, elevation, soil depth, and landform. They found saw 38 percent fewer native species downstream than upstream in 2005, and 26 percent fewer in 2010. Between 2005 and 2010, exotic-species richness increased 220 percent downstream and 300 percent upstream, suggesting that the decreased diversity seen in 2005 persisted despite the flood.

VEGETATION OF THE ELWHA RIVER ESTUARY
Patrick B. Shafroth, USGS Fort Collins Science Center, Fort Collins, Colo.; Tracy L. Fuentes; USGS Northwest Area, Seattle, Wash.
Poster 30; Thursday, 4:30 - 6:30 p.m., Sciences Building
The Elwha estuary supports one of the most diverse coastal wetland complexes described in the Salish Sea region. Scientists identified six primary vegetation types and 121 plant species in a large portion of the estuary. Most of the estuary is dominated by woody vegetation types, especially mixed riparian forest, followed by riparian shrub; willow-alder forest; shrub-emergent marsh transition vegetation; dunegrass; and emergent marsh. The scientists have documented the abundance, distribution, and floristics of these types of vegetation.


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