Humans have relied on salmon for as long as we have lived on the coastlines and rivers of the northern hemisphere – or the ‘salmonshpere’ as it is starting to be known. From the native peoples of the northwestern edge of the Pacific Ocean to the Salish people of Puget Sound, salmon were the currency and lifeblood of their daily existence and culture. This week in 2020, as we celebrate Earth Day and renew our connection to the natural environment, we do so in the spirit of native peoples who have understood for millennia that salmon are a gift from nature to be recognized, honored and celebrated.
This 50th anniversary of Earth Day is a good time to reflect on our relationship to this keystone species, what their plight and recovery tells us about our own condition, and where we see hope on the horizon. On the first Earth Day in 1970, concerns were mounting here and around the world about rivers on fire and unbreathable air. But salmon harvests in Pacific Northwest (BC, WA, OR and CA) were still relatively robust. Fortified by millions of hatchery fish and nurtured by a streak of good ocean conditions, harvests in the region numbered between 35 and 60 million fish. And in 1974, Tribes successfully reclaimed their treaty rights to fish in their usual and accustomed areas through the Boldt Decision, and were designated co-managers of the resource, along with the state of Washington.
However, happy days were short-lived here for people and salmon. In the late 1980s, salmon populations and harvests started to plummet. By the late 1990s when wild Chinook, chum, coho, sockeye and steelhead were being listed under the federal Endangered Species Act (ESA), salmon populations in the Northwest were already extinct in as much as 40% of their former spawning areas, and harvests were reduced to a quarter of the highs from previous decades. In a stark reality check, the harvest of all salmon species combined in British Columbia last year was the lowest on record, only 1.6% of peak harvest 35 years ago. A combination of factors led to this decline, and while harvest was immediately ratcheted back, other threats are requiring significant work to pin down and address.
The community response in Washington state to salmon ESA listings was both immediate and novel. We would take on the responsibility to execute our own plans for recovering habitat for salmon, watershed by watershed, community by community. Tribes, local governments, forest managers, business and NGOs all contributed. This bottoms up, “can do” approach became known as the “Washington Way”, and has guided recovery efforts since 1999. The critical need now is adequate funding to implement.
Presaging this hands on approach, Long Live the Kings (LLTK) was founded in 1986 by salmon advocates wondering if they could sustainably supplement salmon populations by working in concert with habitat restoration and fisheries managers to help restore wild salmon and support sustainable fisheries. LLTK started out by running three novel field facilities, two based on natural rearing techniques and one focused entirely on rescuing wild salmon populations at risk of extinction. LLTK’s trajectory since then has mirrored the evolution of salmon management and recovery. We have led on important and consequential efforts like guiding hatchery reform, understanding poor marine survival and infusing recovery plans with community input and data on climate change. For over three decades, LLTK has worked to advance science, improve management and implement solutions for salmon and people.
On this 50th Earth Day, let’s take stock of where we’ve been, where we are, and where we want to go, and let this be the first day of the next 50 years protecting our salmon, our communities, and our planet.
Microplastics in our water is a relatively new problem and many are rightfully concerned. Spurred by encouragement from the broader LLTK community, we reviewed the available research to determine if marine plastics pose a threat to salmon survival. The following information is based on studies assessing marine plastic effects on zooplankton and fish conducted inside and outside of the Salish Sea. We looked specifically at zooplankton and forage fish when reviewing available research because they are important food for salmon and may play a role in transferring plastics through marine food webs.
As many of us know, plastic is a pervasive human-caused pollutant in the marine environment. Plastics can enter the marine environment either from marine-based activities like fishing, aquaculture, and shipping, or land-based activities that result in wastewater effluent, runoff, or river discharge (Desforges et al. 2014). When we’re thinking about plastics affecting salmon, size matters. Smaller sized plastics less than 5 millimeters, also known as microplastics, are concerning because they are the most likely to be consumed by juvenile and adult salmon either intentionally (they can look like food) or accidentally.
Upon consumption, marine plastics can physically and chemically affect zooplankton and fish. Physical effects from eating it can obstruct their mouths and throats, block their digestive track, artificially fill their stomachs, and be absorbed into other parts of their body (Cedervall et al. 2012; Cole et al. 2013; Rochman et al. 2013; Desforges et al. 2014, 2015). Chemical effects may also occur from the toxic ingredients in the plastic (e.g., petroleum products) or from environmental chemicals that attached to the plastic from seawater (e.g., PCBs) (Cole et al. 2013; Rochman et al. 2013; Hipfner et al. 2018). It’s important to note that effects from plastics may be unique among species, types of contaminants, and types and sizes of plastics (Desforges et al. 2015; Ašmonaitė et al. 2018).
Despite marine plastic pollution being a widely known environmental issue, very little field research has been done in our region to assess how salmon are affected after consuming marine plastic either directly or via their food. Most of the research assessing effects has been laboratory-based and results are often varied. In 2019, researchers performed a thorough review of plastic effects on marine organisms and found an effect was more likely to be detected at higher concentrations of microplastics and mortality occurred at extreme concentrations that are not typically found in the environment (Bucci et al. 2019). This review indicates that field studies may provide a more realistic understanding of exposure and consumption rates for target species, such as salmon.
Along the British Columbia coastline, two different field studies assessed marine plastic consumption rates for zooplankton and forage fish, important food for salmon. In the first study, scientists determined about 3% of copepods and around 6% of euphausiids (AKA krill) were eating microplastics and that there was no correlation between the amount of microplastics eaten and the amount in the seawater (Desforges et al. 2015). In the second study, scientists determined that very few forage fish, sand lance (1.5%) and herring (2.0%), had eaten microplastics (Hipfner et al. 2018). This research also suggested that larger forage fish are less likely to consume plastic. Together, these studies indicate that zooplankton and forage fish are most likely NOT conduits for indirect plastic consumption in salmon on the outer coast of British Columbia.
As was mentioned previously, very little is known about the impacts of marine plastics on salmon either through direct consumption or via their food (pers. comm. A. Spanjer 2019). The first and only field study regarding plastic consumption rates by salmon in the Salish Sea determined juvenile Chinook consume an average of 1.15 microplastic pieces per day (Collicutt et al. 2018). At this rate of consumption, it is unlikely to lead to significant mortality events. This study also found no significant relationship between the amount of microplastics found in seawater and sediment compared to the amount consumed by the juvenile Chinook. The United States Geological Survey (USGS) is currently doing a laboratory-based study examining how long polyester fiber is retained in the gut of juvenile Chinook after consumption, but that research is currently ongoing (pers. comm. A. Spanjer 2019).
Based on the available research investigating marine plastic effects on zooplankton and fish, we can conclude that marine plastics do not currently pose a significant threat to salmon survival in the Salish Sea. However, marine plastics will continue to persist as pollution on land and in our oceans if we do not take action to reduce them. Ellen MacArthur with the World Economic Forum estimated that the world’s oceans will have more plastic than fish by 2050. Whether her estimate is accurate or not, we can all do our part to help reduce plastic pollution. Please see below for a list of five ways you can reduce marine plastic pollution:
- Join a beach cleanup – Puget Soundkeeper Alliance and The Surfrider Foundation are frequently hosting beach and lake cleanups to reduce the amount of debris in our waterways.
- Remember your reusable containers – Actively using your reusable water bottle, coffee mug, or to-go containers will not only reduce plastic but can save you money in the long run.
- Buy microbead-free products –Microbeads are too tiny to be filtered out at the wastewater treatment facility. Buying personal products that do not contain microbeads will reduce the amount of microplastics entering our oceans.
- Reduce clothes washing – When we wash our clothes, they shed microfibers that do not get filtered out, like microbeads. By reducing how often we wash our clothes, we can lower the number of microfibers that are being released. We’re not saying wear dirty clothes, but if you can, wear items more than once and choose natural fiber clothing (these fibers will biodegrade over time).
- Make informed decisions – As consumers, we can make conscientious decisions about the products we buy and the companies we support. This can take the form of buying items in bulk rather than individually wrapped items, as well as the packaging our purchases come in. By being aware of how much plastic your household generates, you can find ways to reduce it and ultimately lower your carbon footprint.
Ašmonaitė, G., Larsson, K., Undeland, I., Sturve, J., Almroth, B.E. 2018. Size matters: Ingestion of relatively large microplastics contaminated with environmental pollutants posed little risk for fish health and fillet quality. Environ. Sci. Technol., 52: 14381 – 14391.
Bucci, K., Tulio, M., Rochman, C.M. 2019. What is known and unknown about the effects of plastic pollution: A meta-analysis and systematic review. Ecological Society of America, doi:10.1002/eap.2044.
Cole, M., Lindeque, P., Fileman, E., Halsband, C., Goodhead, R., Moger, J., Galloway, T.S. 2013. Microplastic ingestion by zooplankton. Environ. Sci. Technol.,47: 6646 – 6655.
Collicutt, B., Juanes, F., Dudas, S.E. 2019. Microplastics in juvenile Chinook salmon and their nearshore environments on the east coast of Vancouver Island. Environmental Pollution, 244: 135 – 142.
Desforges, J.W., Galbraith, M., Dangerfield, N., Ross, P.S. 2014. Widespread distribution of microplastics in subsurface seawater in the NE Pacific Ocean. Marine Pollution Bulletin, 79: 94 – 99.
Desforges, J.W., Galbraith, M., Ross, P.S. 2015. Ingestion of microplastics by zooplankton in the Northeast Pacific Ocean. Arch. Environ. Contam. Toxicol., 69: 320 – 330.
Gall, S.C. and Thompson, R.C. 2015. The impact of debris on marine life. Marine Pollution Bulletin, 92: 170 – 179.
Hipfner, J.M., Galbraith, M., Tucker, S., Studholme, K.R., Domalik, A.D., Pearson, S.F., Good, T.P., Ross, P.S., Hodum, P. 2018. Two forage fishes as potential conduits for the vertical transfer of microfibres in Northeastern Pacific Ocean food webs. Environmental Pollution, 239: 215 – 222.
Rochman, C.M., Hoh, E., Kurobe, T., Teh, S.J. 2013. Ingested plastic transfers hazardous chemicals to fish and induces hepatic stress. Scientific Reports, 3: 3263.
Megan Moore, a researcher from NOAA’s Northwest Fisheries Science Center, discusses her group’s research, partnered with Long Live the Kings, to help recover steelhead populations throughout the Puget Sound. We’re grateful for Megan’s work to help us recover steelhead in Puget Sound!
Long Live the Kings and Seattle City Light have been proud partners in salmon recovery since LLTK’s inception. Together, we power projects around our region that help salmon and steelhead overcome the many challenges they face. This most recent City Light project in Stossel Creek is just the type of work we want to see our private, public, and nonprofit partners coming together to accomplish.
In 2015, Seattle City Light purchased and is in the process of restoring a 154-acre property along Stossel Creek, a tributary to the Tolt River in eastern King County, Washington. City Light purchased the property as part of its proactive Endangered Species Act Land Program, which purchases property containing important habitat for endangered and threatened fish species. This program was established by the City of Seattle in 1999 under Resolution 29905 to help restore and protect habitat for fish protected under the Endangered Species Act (ESA). Stossel Creek is a tributary in the Snohomish River watershed approximately 30 miles east of Seattle, which provides important habitat for ESA-threatened steelhead and coho salmon. The City Light property contains over 3,500 feet of Stossel Creek as well as an additional 1,300 feet of an unnamed creek and wetlands. Steelhead and coho spend a significant portion of their life as juveniles in streams, so protecting or improving the creek habitat on the property can improve the water quality of the creek as well as the river.
The previous owner logged portions of the Stossel Creek property in 2012, which had not been replanted at the time of purchase. Erosion from the logged areas and dirt access roads may contribute sediment to streams where it can smother steelhead and coho redds, killing the eggs, or get trapped in fish gills, impairing breathing. Thus, key objectives in purchasing the property were to protect the wetlands, soils, and streamside vegetation and to reforest logged portions of the site. Trees provide shade that maintains cool water temperatures in streams and associated wetlands, a critical need particularly in the summer months. Trees also provide habitat for insects that are a food source to both fish species.
City Light looked for outside funding to aid with replanting the site, and in doing so developed a unique partnership with Mountains to Sound Greenway Trust, Northwest Natural Resource Group, and Seattle Public Utilities (the Partners), to apply for and receive a grant from the Wildlife Conservation Society, supported by the Doris Duke Charitable Foundation, as well as funds from Carter Subaru of King County. As the Partners planned the replanting of the Stossel Creek property with the objective of reforesting the site, they took the long view of how the climate will change as the site matures. As climate changes, so too will ecosystems that are shaped by it. The Partners in this project used this understanding to plan a forest restoration project that takes into account the expected changes in climate to ultimately result in a more complex and resilient forest structure by the end of the century. Rather than reforest in a traditional way, this Stossel Creek site was planted using a climate-adapted approach.
The Partners’ approach included planting tree seedlings from seed sources originating from southwestern Oregon and northern California, where the climate is similar to the warmer and drier summer climate expected at the Stossel Creek site during the mid to late 21st century. These seedlings were planted alongside locally sourced Douglas-fir and Western redcedar. A total of seven different tree species native to the Pacific Northwest, both deciduous and coniferous, were planted to provide relatively high species diversity. This method increases the functional redundancy of a forest – meaning, forest resilience that comes from multiple species from different taxonomic groups playing similar roles in the ecosystem. Plantings were located away from natural regeneration and grouped by associations suitable for local site conditions such as soil type and aspect. Trees were planted in a wider spacing than traditional methods to decrease the potential for competition during future droughts. These strategies were designed to increase the chances for long-term success of the forested landscape on the Stossel Creek property. Success will be determined through at least a decade of monitoring of tree health and survival within established monitoring plots.
The climate-adapted reforestation of the Stossel Creek property is a novel project designed to explore new replanting strategies that intentionally account for climate change. Through an innovative public-private partnership, this project demonstrates the use of new tools and approaches to restoring and conserving natural resources available today, with the ultimate goal of establishing a resilient forest into the foreseeable future and ameliorating expected climate impacts to aquatic habitat. Demonstrating and recognizing the role of these practices in creating more-resilient forests can help land managers plan and implement more comprehensive approaches to forest restoration and, in this case, fish habitat protection as the climate changes.
Links to film coverage:
The salmon lost a king this week. The world lost a beacon of civility, and a guide to integrity and commitment. And Long Live the Kings lost a leader and a friend.
Bill Ruckelshaus was a member of our board of directors from 1996 to 2015. He was a pragmatic optimist, a respecter of science, and supremely skilled at pulling people with disparate points of view together to craft a new approach.
He strongly believed communities should be empowered, and if needed pushed, to work as one to solve their own problems. To save salmon and restore its populations to abundance was something no single group, government agency, or strategy could accomplish. “It’s not enough,” he used to say, “to stand on shore and throw rocks at the ship of state as it passes by.” To him, bringing the salmon home and ensuring they had a home to come to is the work of all of us, together.
We will miss his great good humor, his engagement at board meetings and events, his inspiration, and his support. With Bill aboard, anything and everything was possible.
Our sympathies and condolences go to Jill Ruckelshaus and the family.
We’ll treasure Bill’s friendship. For the long run.
Prepared by Barbara Cairns, LLTK Executive Director 1997-2010, and Jacques White, current LLTK Executive Director.
As we have heard time and again over the last year, our southern resident orcas are in trouble. There simply isn’t enough salmon to support them, and other factors make this deficit more consequential. They consume fat reserves filled with accumulated toxics while they desperately forage for salmon, a task made more difficult by our noisy waters. It’s a troubling combination of challenges, but salmon recovery is likely to have the largest impact.
Long Live the Kings (LLTK) has worked for decades on efforts to the increase survival and population size of salmon and steelhead that provide the prime sustenance for our orcas. Last year, in response to worrying population declines, Governor Inslee convened the Southern Resident Orca Task Force to address the crisis. LLTK has participated from the start of this effort as the only salmon recovery nonprofit at the table. Since then, orca recovery has occupied much of the region’s attention, and LLTK is using our salmon expertise to bring our resident orcas more food.
In November, the task force delivered 36 first-year recommendations, which the Governor and state agencies advanced to the state legislature for approval and funding. Notably, over 20% of these recommendations were influenced by LLTK’s work, mostly driven by ongoing findings from the Salish Sea Marine Survival Project.
In what is being acknowledged as the best session for environmental legislation in four decades, this spring the legislature passed key orca policy protections related to noise, vessel traffic, toxics, oil spills and shoreline habitat. Both the Governor and the legislature deserve praise for these very positive outcomes.
But not all of the needed actions have been implemented, and there is still much work to do. Shovel-ready Chinook recovery projects have only received about a quarter of what is necessary over the past decade. So clearly, much more effort is needed to fully fund salmon recovery, LLTK is working with our partners to secure funds to support this work.
To this end, LLTK again travelled to Washington, DC this past May as a part of ‘Puget Sound Day on the Hill’ and ‘Salmon Day on the Hill’, along with over 80 stakeholders from the west to meet with members of Congress and present the importance of a healthy Puget Sound and Pacific salmon recovery. During the DC visit, LLTK was invited to give a presentation on the Salish Sea Marine Survival Project and facilitate a panel of NW restoration experts for the Congressional Estuarine Caucus, a group of elected officials invested in protecting important water bodies around the country. The trip resulted in increases in federal funding and renewed focus, as Congressman Derek Kilmer has requested to visit the LLTK Lilliwaup Field Station this summer.
Back in the Northwest, we are happy to announce that you helped us raise over $12M for the Salish Sea Marine Survival Project, smashing our $10M goal for this ground-breaking international project. Results from the project have already been incorporated into National Oceanic and Atmospheric Administration’s Recovery Plan for federally listed Puget Sound steelhead, which will be released at the end of this year.
Our work with members of the Washington State Legislature is also proving to be successful. In the most recent legislative session, we helped secured $1.5M for the Salish Sea Marine Survival Project and $10M for the Middle Fork Dam removal. This dam removal project is supported by American Rivers, the Paul G. Allen Family Foundation and the City of Bellingham and will provide access to 16 miles of previously blocked river habitat for federally listed Chinook and steelhead.
The Hood Canal Bridge Ecosystem Assessment is nearing completion for Phase 1 research. LLTK and project partners are working to synthesize and report on our findings, and are now beginning to plan for Phase 2, solutions testing. Preliminary Phase 1 results suggest that many steelhead experience the bridge as a physical barrier, delaying migration, and indicate predation by a deep-diving, warm-blooded animal. Predation may be associated with patterns of fish biomass, predator location, and localized water flow in surface waters near the bridge.
Survive the Sound, our education and outreach campaign that invites the public to track their favorite fish through an epic migration, completed its third year. The campaign has assisted LLTK in graphically and interactively communicating the impacts of the bridge on juvenile steelhead to the public. This year we quadrupled participation, and nearly 2,000 of the participants were educators who reported serving over 200,000 students! And over half of the educators surveyed reported that they were not covering salmon issues prior to participating in Survive the Sound. If you raced with us, did your fish survive? What did you learn? If you missed the campaign this year, you can still visit SurvivetheSound.org to pick your favorite fish and watch its migration.
Finally, LLTK is working with our state, tribal, federal, and nonprofit partners in the US and in Canada to perform limited experiments at hatcheries to see if we can improve the survival and size of returning Chinook. This could eventually benefit southern resident killer whales and fishers, and teach us lessons we can translate to wild fish recovery.
At our Glenwood Springs Hatchery, LLTK will be rearing experimental groups, in addition to our standard May release, that will be reared slowly and released later. Slow rearing is done in attempt to delay maturity down the road and return bigger, older fish. There is strong alignment between this effort and the findings of the Salish Sea Marine Survival Project, the distribution and timing of releases could address potential issues of competition, predation or changes in food availability.
Clearly, LLTK is moving forward on many fronts to increase the abundance and resilience of salmon in our region, and by extension, hoping that our efforts are successful in providing more food for our southern resident orcas. Your significant support of our work has allowed LLTK to push the boundaries of what’s possible, moving ahead faster, taking bigger risks in more places, and having a bigger positive impact on our region and our future. Thank you for being a partner in our mission to save a Pacific Northwest icon.
Just a few weeks ago, we received word that there is new J-pod calf spotted in NW waters. This is reminder that we should have hope, that nature is resilient if we give it a chance. Thank you for being part of that hope, you give our salmon, steelhead and whales a chance to survive and thrive.
Harbor seals are protected by the Marine Mammal Protection Act (MMPA). At the same time, they are believed to be a significant predator of threatened Chinook salmon and could be competing with endangered southern resident killer whales. This poses a challenging management trade-off and data describing harbor seal’s historic impact on our food web, which would help guide this trade-off, is limited. By using old bone specimens stored at local museums and the scientific methods, researchers at University of Washington are uncovering more information.
Harbor seals experienced exponential growth in Puget Sound following the implementation of the MMPA, from historic lows of approximately 2,100 in 1972 before leveling off at the current population size of 18,000 (Jeffries et al. 2003). This change in predator abundance has been correlated to declines in forage fish and salmonid survival across the WA coast, which suggests harbor seals pose a threat to the recovery of endangered and vulnerable species in the region, including Chinook salmon and southern resident killer whales (Thomas et al. 2017).
However, this change in predator abundance also coincided with a broad-scale environmental regime shift known as the Pacific Decadal Oscillation in 1977/78, a phenomenon that has also been linked to productivity of fish species in WA, including salmon. Teasing apart these ecological drivers is challenging yet important for management of the Sound as an integrated system.
At the University of Washington, members of the Holtgrieve Ecosystem Ecology Lab, led by gradate student Megan Feddern, are trying to better understand the interactions between harbor seals, their prey and environmental changes to better inform management decisions from an ecosystem-based approach. They aim to do this by:
- Creating a dataset of where harbor seals have been feeding in the coastal WA food web over the past 100 years from museum skull specimens.
- Combine this dataset with other historic datasets of environmental drivers (Pacific Decadal Oscillation, El Niño Southern Oscillation, sea surface temperature) and important harbor seal prey species (herring biomass, salmon populations, Pacific Hake biomass) to identify what ecological components drive harbor seal food web position.
The research is made possible using a recent methodological advancement called compound specific stable isotope analysis of amino acids. Scientists are able to measure the nitrogen isotope ratio (15N/14N) of eleven different amino acids preserved in bone collagen. A small piece of bone (50 mg) is decalcified to access preserved collagen and measure the 15N/14N of the amino acids contained within that collagen and calculate the food web position of the harbor seal that collagen came from. Certain amino acids, called trophic amino acids, show an increase in 15N relative to 14N as an animal feeds higher in the food web. In other words, they’re able to get a better idea whether seals are eating, for instance, more herring or salmon.
During the study, 150 museum harbor seal skull specimens from seals from 1920-2017 have been obtained and the 15N/14N of their collagen has been measured. Scientists now have estimates of harbor seal food web position from the Hood Canal and Puget Sound during that time period, which they are currently comparing to data sets describing different environmental drivers.
Stay tuned for the full results!
This article was created using a flyer from the University of Washington. View it here.
Anthony’s and Long Live the Kings began building a partnership in 2014. The restaurant’s founder, Budd Gould and his son Herb (CEO of Anthony’s), found that their vision to preserve the health and well-being of the seafood industry aligned perfectly with Long Live the Kings’ mission to recover wild salmon and steelhead. Budd’s other son, JJ, who is a retired Chief of Wildlife for the Idaho Fish and Game and a certified Wildlife Biologist, was nominated to join the Long Live the Kings’ Board of Directors in 2016. Our partnership has grown ever since.
When we introduced Survive the Sound to the team at Anthony’s, they wanted to help make this innovative campaign a reality. They were excited for opportunity to bring information about salmon recovery to students and the public. We’ve both known that passionate salmon conservationists are often born after enjoying and learning about this precious resource. Anthony’s saw the opportunity to help create this experience for their guest.
“Providing our guests and the rest of the public with accurate information on salmon and our environment is an important step to making better decisions that benefit future generations,” says Budd. “It is an honor and a privilege to be able to partner with an organization like Long Live the Kings that are so dedicated to this very mission.”
Long Live the Kings is thrilled to have a partner like Anthony’s to help bring our mission to a broader audience. The generosity and dedication from companies like Anthony’s allows us to push the boundaries of salmon recovery; to explore new ideas and take on new challenges. Anthony’s is a leader among the growing number of local companies who are setting a high bar for investments in their local environment, empowering us to protect and restore the Pacific Northwest we want to leave for our children.
Salmon are an important part of our life and diet, but we share this resource with many other species. Birds, seals, sea lions, bears, porpoise, whales, and other fish all depend on salmon for a portion of their diet. With salmon and steelhead populations at risk, many people are asking if too many mouths are at the salmon buffet.
In Puget Sound and the Strait of Georgia, Long Live the Kings and our partners are looking at the whole ecosystem to figure out what’s killing young salmon and steelhead on their migration through Puget Sound. In some cases, as few as 10% of the fish survive to reach the Pacific Ocean. Scientists refer to this problem as high juvenile marine mortality.
One aspect of our research considers whether salmon predators are contributing to high rates of juvenile marine mortality, but we’re finding that the story is much more complicated. Interestingly, human harvest of salmon isn’t a significant factor in the case of high juvenile marine mortality because humans aren’t allowed to harvest juvenile salmon and steelhead. That’s not to say that humans aren’t a major factor contributing to these salmon deaths. There is evidence to suggest that human activity and decisions are driving a number of problems: limited prey for young salmon, a lack of estuary habitat, contaminants, and disease.
Humans have even facilitated the increase in marine mammals through the passage of the Marine Mammal Protection Act. This important law has worked well to protect many marine mammals from harassment and death, but people are wondering if it’s worked too well for some species.
Current research suggests harbor seals are eating many salmon. In Puget Sound alone, the harbor seal population has increased three-fold since the 1980s, a time when our salmon survived at much higher rates (Jeffries et al. 2003). While we are still working to better understand their impact on salmon recovery, initial studies suggest seals and sea lions may be consuming two times as many Puget Sound salmon as are caught by humans, with seals being the primary consumer (Chasco et al. 2017).
If a seal boom is contributing to the further decline of already-threatened salmon and steelhead populations in Puget Sound, we need to answer more questions to address the problem. How many seals should there be? What should they be eating? Who’s eating them, or isn’t eating them? Are there factors that make it easier for these predators to hunt salmon? While we don’t have complete answers to these questions, and continued research is absolutely critical to making thoughtful decisions, our work has uncovered some new ideas which give us options to start investing in solutions.
Seals are opportunistic predators, but by analyzing their scat, we know their diets rely heavily on forage fish. Young salmon, steelhead, and forage fish often swim amongst each other in the areas where seals hunt. With declining forage fish populations, some scientists hypothesize that seals may end up eating more salmon and steelhead to compensate. This indicates that rebuilding forage fish populations could help rebalance the food web and take some pressure off of salmon and steelhead.
Transient killer whales are the primary predators for seals and they have been spending more time in the Salish Sea (Puget Sound, Strait or Georgia, and Strait of Juan de Fuca). Estimates suggest that transients eat about 1,090 seals from the Salish Sea each year. Their presence is helping to naturally control seal populations. Reducing noise pollution, contaminants, vessel collisions and preventing oil spills will help ensure that our waters are safer for these whales.
A number of factors may also make salmon and steelhead predators more successful.
- Barriers like the Hood Canal Bridge, Ballard Locks, and dams can slow the progress of migrating fish. Smart predators learn to take advantage of these situations.
- Consolidated releases from hatcheries may be acting like a dinner bell for predators. Studies have shown predators can change their behavior in response to large hatchery releases. Most Puget Sound hatchery Chinook are released during the same two-week window.
- Salmon and steelhead that are affected by contaminants or contract diseases may be slower and easier targets for predators. Just like humans, unhealthy fish have trouble operating at their best, which is very important during their arduous migration.
Long Live the Kings and our partners are working to address these factors, which could give salmon and steelhead a better chance of avoiding predators and making it to the Pacific Ocean.
Our research and approach to recovery looks at the big picture to implement lasting solutions that restore our ecosystem – an ecosystem that will thrive if given the chance. This approach requires thorough planning, considerable funding, and cooperation from others. But, if we’re going to save salmon and steelhead, we’re going to need to restore our ecosystem, and that starts by understanding it better.
Chasco et al. (2017) Estimates of Chinook salmon consumption in Washington State inland waters by four marine mammal predators from 1970 – 2015. DOI: 10.1139/cjfas-2016-0203
Jeffries et al. (2013) Trends and Status of Harbor Seals in Washington State: 1978-1999, Journal or Wildlife Management 67(1):208–219
Image Credit: Vancouver Aquarium. LLTK use “seal-packs” that help us research predator-prey interactions.
The Ray’s team including owners, managers, chefs, servers and hosts all joined together this week to restore critical salmon habitat along the Snoqualmie River.
We teamed up with our non-profit partner Long Live the Kings to volunteer for a day with Stewardship Partners, a local non-profit committed to habitat restoration in the Snoqualmie Valley to help maintain economic viability of farms and forestland while helping landowners restore fish and wildlife habitat.
We worked to remove invasive plant species and install native trees and shrubs to enhance salmon habitat and restore the riverbank on an 80-acre farm in Carnation. The plants will eventually provide shade for the river that will help keep water temperatures low, providing an optimal environment for salmon to thrive.
It was a great day working outside as a team to help keep our local salmon habitats alive and well! Check out some photos from the day below.
Learn more about Stewardship Partners and how to get involved at stewardshippartners.org.