Western Fisheries Science News, August 2017 | Issue 5.8
The Puget Sound—one the largest estuaries in the country and part of the greater Salish Sea—is the hub of a thriving economy and home to a growing human population. It is also home to birds, seals, whales, and fish, including the iconic salmon. Salmon in the Puget Sound play an important role in the ecosystem as well as the lives of people living in the area, including Native Americans. However, declines in salmon numbers are of concern for existing ways of life for both marine and human populations.
In the early 1980s, Chinook salmon populations in the Puget Sound experienced steep declines, leading to their listing under the Endangered Species Act (ESA). This led to restrictions in land and water use in the region, as well as limits on tribal, recreational, and commercial fishing. Declining numbers have been attributed to lower survival during marine life stages, so identifying factors or processes that limit marine survival are essential for restoring salmon in this region. Historically, our collective understanding of what drives salmon and steelhead survival in saltwater has been extremely limited, and has been acknowledged by natural resource managers as a critical information gap that must be addressed in order to make real progress toward salmon recovery and sustainable fisheries.
USGS researcher Dr. Dave Beauchamp, along with his teams at the WFRC, University of Washington, and collaborators, has been addressing some important questions about marine survival of juvenile salmon. They are tracking the growth, feeding, and survival of juvenile Chinook salmon through river, estuarine, shoreline, and offshore marine habitats for multiple river drainages and marine regions of Puget Sound. Their work covers multiple years. Research has found that the growth and weight achieved during the first month of feeding in offshore habitats within Puget Sound strongly influences survival to adulthood. The availability and contribution of larval crab to juvenile growth during this critical period accounts for most of the variability in body size during July. It is strongly positively correlated with marine survival of hatchery Chinook over the past decade. Therefore, continued research into whether feeding, growth and survival relationship for wild Chinook parallel these findings for hatchery fish, and examining how larval crab availability varies and what affects its abundance among regions during critical growth periods will guide effective salmon restoration by determining whether to focus on specific water quality challenges, crab harvest or habitat, competitors or predators of juvenile salmon.
”It’s been fascinating to learn how juvenile Chinook salmon balance challenges of variable temperature regimes, limited food, and changing foraging capability as they transition through early marine life stages, and how these balancing acts differ among watersheds,” said Dr. Beauchamp, ”We see that juveniles from most watersheds use the estuarine delta and shoreline habitats to achieve moderate growth while acclimating to marine life, then shift to offshore habitats of Puget Sound to maximize feeding and growth during their critical growth period in mid-June and July.” Beauchamp adds, “Temperatures in the shallower estuarine deltas and shorelines warm quickly and can inhibit growth or become inhospitable earlier during some years and in some regions, whereas temperatures offshore at that same time remain cooler and near optimal for growth.”
This research is part of a larger effort, led and supported by Long Live the Kings, to understand what in the marine environment is negatively affecting salmon, steelhead and forage fish and how we can change them. Their mission: restore wild salmon and steelhead and support sustainable fishing in the Pacific Northwest. They combine innovative field work, pioneering science, and sophisticated new management tools to help decision-makers advance salmon recovery while balancing the needs of fish and people. WFRC supports their mission by providing the critical science information to better understand the complex relationships between fish and their role in the food web.
Newsletter Author - Rachel Reagan
USGS Provides Interpretive Talk on White Salmon River: On August 27, 2017, researcher Jill Hardiman provided an interpretive talk at the 3rd Annual Community Interpretive Float on the White Salmon River, WA. The event is part of the Columbia Riverkeeper’s Love Your Columbia Day. Hardiman spoke about recolonization of fish following dam removal on the White Salmon River. USGS has been monitoring juvenile salmonids in the White Salmon River Basin to better understand abundance trends, distribution, and life history patterns of recolonizing salmonids and to assess efficacy of natural recolonization to inform management decisions.
USGS Invited to Attend Dam Removal Workshop: On August 23-24, 2017, researcher Jeff Duda attended a workshop sponsored by the U.S. Army Corps of Engineers in New York, NY, to evaluate impacts of sedimentation associated with dam removal. Duda, who has been involved with evaluating the ecosystem response following dam removals on the Elwha River and synthesizing dam removal science at the Powell Center, was invited to participate with a small forum of colleagues who are experienced with dam removal issues.
In the News
On August 22, 2017, fish biologist Nancy Elder was contacted by Alison Morrow from King 5 News (Seattle, WA) about an interview and field visit during dive surveys nearshore of the Elwha River. The interview was filmed August 30th and aired on September 1, 2017.
During the week of August 21, 2017, USGS Center Director Jill Rolland was mentioned in various news media outlets, including The Columbian, U.S. News, and the AP, about concerns related to net pen holding 305,000 farmed Atlantic salmon in Washington state that collapsed and released thousands of fish into Puget Sound.
On August 10, 2017, Steve Waste was interviewed in Seattle by May Lee of CGTN (China Global Television Network). The interview focused on the issues surrounding migratory species in the Northwest, their return to spawn and the challenges faced including the lack of fish passage at many blockages. China faces similar issues with their native carp (as well as many other species). Steve Waste provided information about USGS research on fish passage challenges and potential solutions.
Hansen, A.C., T.J. Kock, and G.S. Hansen. 2017. Synthesis of downstream fish passage information at projects owned by the U.S. Army Corps of Engineers in the Willamette River Basin, Oregon. U.S. Geological Survey Open-File Report 2017-1101. DOI: 10.3133/ofr20171101.
Foley, M.M., J.R. Bellmore, et al. Dam removal: Listening in. 2017. Water Resources Research 53(7): 5229-5246. DOI: 10.1002/2017WR020457.