1

20th Salmon Ocean Ecology Meeting Salmon in dynamic habitats and food webs

March 3-4

Recent decades featured significant trends and variability at multiple dimensions of marine habitat for salmon. Interactions between predator demand, environmental variability, hatchery practices, and salmon population dynamics need to be elucidated, modeled, and ultimately may need to be mitigated. We envision a salmon ocean ecology meeting that focuses on these aspects of the seascape and provides applications of and introductions to relevant survey and modeling tools.

2

Venue Some Hotels (details online)

1. Hopkins Marine Station A. Martine Inn 2. Monterey Bay B. Spindrift Inn

C. Wave Street Inn D. Best Western E. Centrella Inn F. Borg’s Oceanfront Motel

3

8:00 – 8:45 Registration 8:45 – 9:00 Welcome 9:00 – 9:40 Nate Mantua. Causes for Northeast Pacific marine heatwaves in the 2000s 9:40 – 10:00 Stephanie Taylor, Vladimir Radchenko, Laura R. Tessier, Mark Saunders and

Moronke K. Harris. Investigating factors influencing Pacific salmon in the marine environment: the International Year of the Salmon Pan Pacific High Seas Expedition 2021

10:00-10:20 Moronke K. Harris, Anna Vazhova, Mark Saunders, Vladimir Radchenko, Evgeny

A. Pakhomov, and Brian P. V. Hunt. Winter phytoplankton isoscapes in the Gulf of Alaska: decoding Pacific salmon ecosystems on the high seas

10:20–10:40 Laura R. Tessier, Stephanie Taylor and Mark Saunders. Progress of The

International Year of the Salmon initiative in establishing the conditions for understanding the mechanisms affecting Pacific salmon productivity in a rapidly changing world

10:40-11:00 Break 11:00 –11:20 David W. Welch, Erin L Rechisky*, and Aswea D. Porter. The Coast-wide Collapse

of Northeast Pacific Chinook Salmon 11:20-11:40 Annabella Aguirre, Laurie Weitkamp , and Louise Copeman. Are Lamprey like

Salmon? Pacific Lamprey Feeding in Marine Waters 11:40 – 1:00 Lunch

20th Salmon Ocean Ecology Meeting Boat Works at Hopkins Marine Station

Tuesday March 3

Session I Moderator: Brian Wells

4

1:00-1:40 Jerome Fiechter Recent advances in marine ecosystem modeling: a journey

across (fish) scales 1:40-2:00 Erin L Rechisky, David W. Welch, Aswea D. Porter, Stephen Johnson, and Scott

Hinch. Exposure time of free-ranging juvenile sockeye salmon to Atlantic salmon farms in British Columbia

2:00-2:20 James P. Losee, Andrew Claiborne, Derek Dapp, Riley Freeman, Gabe Madel,

Todd Seamons, Anna Kagley, Jessica Miller, Tom Quinn, Gustav Hellström and Daniel Palm. New Insight into the Management and Ecology of Anadromous Cutthroat Trout

2:20-2:40 Brian Beckman, Cheryl Morgan, Meredith Journey, Larissa Rohrbach, Don Van

Doornik. Something's happened: growth and survival of coho and Chinook salmon smolts in the NCC, 2000 – 2019

2:40-3:00 Andrew M. Claiborne, Lance Campbell, Bethany Stevick, Todd Sandell, James P. Losee, Marisa Litz, Joseph H. Anderson and Austin Anderson. Correspondence between scale growth, feeding conditions, and survival of adult Chinook salmon returning to Puget Sound and Coastal Washington: implications for forecasting

3:00-3:20 Break 3:20 – 3:40 Meredith Journey, Brian Beckman, Chrys Neville, Marc Trudel, Cheryl Morgan,

and Don Van Doornik. A comparison of juvenile Chinook salmon growth in the Salish Sea and the Northern California current

3:40-4:00 Colin D. Bull. The Likely Suspects Framework for Atlantic salmon: developing a

multi-disciplinary approach to quantifying the drivers of marine mortality in a changing ocean environment

4:00-4:20 Neala W. Kendall*, Benjamin W. Nelson, and James P. Losee. Density-

dependent marine survival of Salish Sea Chinook and coho salmon associated with pink salmon presence

4:20-4:40 M. Bradley Hanson, Eric J. Ward, and Dawn P. Noren. Is “natural mortality”

being underestimated? The potential impact of predation on Fraser River Chinook stocks by southern resident killer whales in their summer range

Session II Moderator: Brian Burke

5

9:00 – 9:40 Francisco Chavez. Sequencing the ocean: Using environmental DNA to study

marine ecosystems 9:40-10:20 Holland, Melinda and Suzy Kohin. Advanced technologies for tracking salmon in

coastal and open ocean environments 10:00 – 10:20 Lance A. Campbell, Andrew M. Claiborne, Joshua W. Chamberlin, Wade Smith.

Using otolith microchemistry to infer broad scale ocean migratory patterns in select Washington Chinook and coho salmon populations.

10:20 – 10:40 Break 10:40-11:00 Brett T. Johnson, Ray Brunsting, Brian Hunt, Eric Peterson, and Mark Saunders.

The Global Ocean Observation System and Essential Salmon Ocean Ecology Variables

11:00 –11:20 Emily A. Miller*, Andrew C. Seitz, Michael B. Courtney, Matthew Catterson, Jeff

Nichols, Joseph D. Kiernan, John O’Sullivan, Alexander Norton, Kyle S. Van Houtan, Andre Boustany. Ocean movement and behavior of steelhead revealed by pop-up satellite archival tags

11:20-11:40 Andrew C. Seitz, Emily A. Miller, Michael B. Courtney, Matthew Catterson, Jeff

Nichols, Joseph D. Kiernan, John O’Sullivan, Alexander Norton, Kyle S. Van Houtan, Andre Boustany. Interpreting mortality of satellite tagged salmonids

11:40-12:00. Cameron Freshwater and Jackie King. Stock-specific abundance and behaviour of

mature Chinook salmon migrating off Vancouver Island 12:00-1:30 Lunch 1:30-5:00 Discussions related to future directions and current risks

Session III Moderator: Nate Mantua

Session IV Discussion

Wednesday March 4

6

Invited speakers Tues 9:00 Causes for Northeast Pacific marine heatwaves in the 2000s Nate Mantua NOAA Fisheries, SWFSC, Fisheries Ecology Division, 110 MacAllister Way, Santa Cruz, CA 95060, USA (Email: nate.mantua@noaa.gov) In this review I will discuss the causes for the 2013-2016 large marine heatwave in the NE Pacific, and compare and contrast that event with the large marine heatwaves of summer 2019 in the Bering Sea/northern Gulf of Alaska and the lower latitudes of the northeast Pacific. A small number of persistent atmospheric sea level pressure forcing and related surface heat flux anomaly patterns associated with these events will be compared and contrasted. The potential influence of anthropogenic climate change in these events will also be reviewed and discussed. Tues 1:00 Recent advances in marine ecosystem modeling: a journey across (fish) scales Jerome Fiechter University of California, Santa Cruz, Ocean Sciences, Santa Cruz, CA USA (Email fiechter@ucsc.edu) In this presentation, I review recent advances in marine ecosystem modeling with an emphasis on bridging variability at scales ranging from climate to regional and, utlimately, to those associated with the behavior, growth and survival of individual fish and other marine organisms. The primary focus will be on individual-based models (IBMs) and their coupling to regional ocean circulation and lower trophic level ecosystem models, including challenges associated with representing individual life history characteristics and accounting for climate variability at the scale of local habitats. Finally, I draw on recent studies in the California Current to illustrate approaches for modeling regional and climate impacts on sardine and anchovy populations, interannual shifts in foraging patterns and success of California sea lions, and oceanic drivers of juvenile Chinook salmon growth following out-migration.

7

Weds 9:00 Sequencing the ocean: Using environmental DNA to study marine ecosystems Francisco Chavez Weds 9:40 Advanced technologies for tracking salmon in coastal and open ocean environments Melinda Holland and Suzy Kohin Wildlife Computers, 8310 154th Ave NE, Suite 150, Redmond WA 98052 USA (Email: tags@wildlifecomputers.com) Salmon have been studied extensively during their migrations to and from their freshwater natal habitats, while less is known of their behavior at sea. With many salmon populations declining worldwide, it is critically important to understand the impacts of environmental change and human activity on salmon populations throughout their life cycle. The miniaturization of sensors and electronics, and advancements in communication networks have spawned new methodologies for tagging and tracking fish beyond inland and coastal environments. Currently, most salmon tracking studies are conducted using acoustic telemetry, data-logging tags, PIT tags and satellite telemetry. Each of these technologies has its benefits and limitations, and researchers are continually experimenting with new technologies to find ways to monitor smaller fish over greater distances. We will review some of the promising emerging technologies and their applications for tracking salmon and their predators in coastal and open ocean environments including ROAM (RAFOS Ocean Acoustic Monitoring), smaller popoff satellite archival tags, nano-satellites carrying the next generation of Argos instruments, and miniaturized transceivers that can deployed on animals, AUVs and drones.

8

Session I

Tues 9:40

Investigating factors influencing Pacific salmon in the marine environment: the International Year of the Salmon Pan Pacific High Seas Expedition 2021 Stephanie Taylor, Vladimir Radchenko, Laura R. Tessier, Mark Saunders and Moronke K. Harris North Pacific Anadromous Fish Commission (NPAFC), Vancouver, BC, Canada. E-mail: staylor@npafc.org Pacific salmon are an important cultural, commercial, and biological resource for countries of the North Pacific rim. Salmon and the people that depend on them are faced with increasing uncertainty in the behaviour of climate and ecosystems with serious social and ecological implications. As conditions become more and more variable and returns continue to decline, the need to understand factors affecting salmon during all life history stages intensifies. Currently, very little is known about factors affecting Pacific salmon when in the high seas. Historical data in the high seas is sporadic and limited, most surveys conducted in the sixties and seventies. As part of the International Year of the Salmon, the North Pacific Anadromous Fish Commission (NPAFC) with its five member countries (Canada, Japan, the Republic of Korea, Russia and the United States) is planning a Pan-Pacific High Seas research expedition in late winter 2021 to build upon a 2019 expedition to the Gulf of Alaska. As many as five research vessels with researchers from five countries will concurrently survey the North Pacific. The overarching question is, “How will increasingly extreme climate variability in the NPO and the associated changes in the physical environment influence the distribution, migration, and survival of Pacific salmon and the people who depend on them?” We have been working with a group of scientists from around the Pacific Rim to develop a set of hypotheses and research protocols to be undertaken by all vessels. Work on refining the hypotheses and developing the survey plan for all vessels in on going. We will share our progress to date and discuss the information which is expected to emerge from this research. Information from the high seas will ultimately be connected with freshwater and coastal data to give a clearer picture of challenges Pacific salmon face throughout their life cycle

9

Tues 10:00

Winter phytoplankton isoscapes in the Gulf of Alaska: decoding Pacific salmon ecosystems on the high seas Moronke K. Harris1, Anna Vazhova2, Mark Saunders1, Vladimir Radchenko1, Evgeny A. Pakhomov3, and Brian P. V. Hunt3

1North Pacific Anadromous Fish Commission, 502-889 West Pender Street, Vancouver, BC V6C 3B2, Canada (Email: mharris@npafc.org; Tel: 647-523-3170) 2Pacific Branch of the Russian Federal Research Institute of Fisheries and Oceanography (TINRO), Shevchenko 4, Vladivostok, 690950, Russia 3University of British Columbia, Institute for the Oceans and Fisheries, 2202 Main Mall, Vancouver, BC V6T 1Z4, Canada (Email: b.hunt@oceans.ubc.ca; Tel: 778-230-4776) Approximately 55 million Pacific salmon inhabit the Gulf of Alaska (GoA) during winter. Despite the importance of this region, the high seas phase of salmon life history remains poorly understood. The current lack of baseline data on the environmental conditions experienced by overwintering salmonids adds uncertainty to the already challenging task of determining potential implications of climate impacts on ocean productivity for salmon condition and reproductive success in a changing Pacific ecosystem. Plankton stable isotopes (SI; δ13C and δ15N), influenced by nutrients, community composition and physical oceanographic variables, can be used to determine the linkages between bottom-up changes in the abundance and composition of primary producers and consumers that cascade through ecosystems. Isocapes, geographic distributions of SI, have recently been developed for the northeast Pacific based on the relationship between zooplankton isotopes from Continuous Plankton Recorder samples and satellite data. These models demonstrate a strong relationship between isotope values and ocean temperature and productivity, offering a valuable tool for predicting the food web productivity experienced by salmon on the high seas. However, the isoscape models have yet to be evaluated against in situ measurements. As the first comprehensive winter expedition examining factors affecting Pacific salmon in the GoA, the 2019 International GoA Expedition successfully established a baseline of environmental and ecosystem-level measurements for future comparisons. Here, we used carbon and nitrogen SI from phytoplankton collected during the 2019 Expedition to reconstruct aspects of the marine environment experienced by Pacific salmon during the overwintering period of their life cycle within the high seas. Filtered Niskin rosette water samples were collected from the sea surface (~2 m depth) at every grid station (n = 56) to: (i) provide a GoA isotope baseline for application in ocean productivity and trophic studies, (ii) identify spatial variation in isotope signatures that can be used to trace salmon foraging locations and migration and (iii) validate existing predictive models for GoA isoscapes. These high spatial resolution phytoplankton measurements are able to be directly compared to salmon isotope values also collected in situ. Salmon abundance is affected by the abundance and species composition of lower tropic levels. Thus, understanding drivers of lower trophic level variation is essential for understanding cascading changes throughout the high seas ecosystem.

10

Tues 10:20

Progress of The International Year of the Salmon initiative in establishing the conditions for understanding the mechanisms affecting Pacific salmon productivity in a rapidly changing world

Laura R. Tessier1, Stephanie Taylor1 and Mark Saunders1

North Pacific Anadromous Fish Commission, Vancouver, BC, Canada. E-mail: ltessier@npafc.org

Sustaining wild salmon is a complex concern that must be considered in a fiscally viable and culturally relevant framework operating from local to hemispheric scales. Salmon are currently facing many challenges associated with the impacts of the increasing footprint of a growing human population, including the effects of climate change, which have been exacerbated by anthropogenic activities. At present, hundreds of organizations across the Northern Hemisphere are working on salmon-related issues. Yet, despite this broad and deep source of strength, they remain poorly connected and fail to take full advantage of our collective capacity to address shared scientific and management issues. The International Year of the Salmon (IYS) is working with partners to build connections through multiple Signature projects to address major research gaps and develop supporting tools and methods. I will describe our progress in the development of partnerships among academic, government, NGO’s and industry and highlight several projects relevant to the marine salmon ecology research community. One such project is the Likely Suspects (LS), which is already under development in the Atlantic basin with partners such as the Atlantic Salmon Trust and the Missing Salmon Alliance. The LS is a life history-based framework for identifying populations bottlenecks from the High Seas, coastal and freshwater eco-regions ultimately informing life history models to develop and test our understanding of factors driving salmon productivity and assess the efficacy of management actions. In another presentation, Colin Bull will describe the LS in detail, and I will describe our plans for implementation in the Pacific. One of the barriers to the development of life history models and testing hypotheses regarding mechanisms regulating population productivity is rapid access to standardized data related to salmon and the ecosystems they frequent. I will describe several projects underway to understand what inhibits data mobilization and approaches to address the challenges. To address knowledge gaps on challenges salmon face in the high seas, a series of high seas expeditions have been planned under the IYS. Stephanie Taylor will be discussing the upcoming 2021 Pan Pacific expedition and I will briefly describe how this expedition and the previous one in 2019 strengthen work being done through the IYS. Through the IYS we seek to provide a new generation of salmon researchers, managers, and conservationists with a dynamic, well-connected international research and management environment that has timely access to data, methods and tools to respond to a rapidly changing world.

11

Tues 11:00 The Coast-wide Collapse of Northeast Pacific Chinook Salmon David W. Welch1, Erin L Rechisky1*, and Aswea D. Porter1 1Kintama Research Services, 755 Terminal Avenue North, Nanaimo, British Columbia V9S 4K1 Canada (david.welch@kintama.com; 250-739-9044; E-mail: erin.rechisky@kintma.com, 250-667-6951) Accelerating decreases in survival are evident for a wide range of Northern Hemisphere salmon populations. We collated data on coded wire tagged (CWT) and passive integrated transponder (PIT) tagged-based smolt-to-adult survival for the Pacific coast of North America (California to SE Alaska) in order to examine the patterns determining salmon returns. A total of >2,700 years of annual survival estimates were collected for Chinook (Oncorhynchus tshawytscha). We found that over the past half century marine survival collapsed by a factor of at least 4-5 fold to similar low levels (~1%) for most regions of the Pacific coast, although the time that the survival decline started was later to the north. Comparing the five most recent years of SAR data using a bootstrap resampling methodology leads to the conclusion that the survival of all regions of the coast has declined to essentially the same level, so that (for example) the SARs of Snake River Spring Chinook are the same as wild Spring Chinook from SE Alaska, despite the very different freshwater habitats. The observed size of the decline over time in SARs is too large to be compensated by freshwater habitat remediation or cessation of harvest, and too large-scale to be attributable to specific anthropogenic impacts such as dams in the Columbia River or open net-pen salmon farming in British Columbia, as these local issues are absent from SE Alaska. Survival declines later in the marine phase may help explain why Chinook survival has fallen so drastically across the entire west coast of North America although why SARs now seem so similar across much of North America is currently unclear. Projected rates of climate warming are likely to greatly increase in the near future. Managers need to correctly identify the drivers of salmon collapse and respond appropriately.

12

Tues 11:20 Are Lamprey like Salmon? Pacific Lamprey Feeding in Marine Waters

Annabella Aguirre 1, Laurie Weitkamp 2 , and Louise Copeman 2

1 California State University, Monterey Bay, Seaside, CA 93955, USA (Email: annaaguirre@csumb.edu; Tel: 831-737-0569 2 Conservation Biology Division Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA 2032 Marine Science Drive Newport, Oregon 97365, USA (Email: laurie.weitkamp@noaa.gov; Tel: 541-961-6982

2 College of Earth, Ocean and Atmospheric Sciences, Oregon State University, 2030 Marine Science Drive, Newport, Oregon 97365, USA (Email: louise.copeman@noaa.gov; Tel: 541-961-7813

The Pacific lamprey (Entosphenus tridentatus) is a species of importance to West Coast Tribes but little is known about their life history and why there have been recent declines in their population abundance. In particular, very little is known about Pacific lamprey marine ecology. In the absence of lamprey-based information, we’re using the marine ecology of the Pacific salmon as a starting point. This preliminary study focused on the ecology of Pacific lamprey from marine waters, of the northern California Current, specifically using their size, total lipids, lipid classes, and fatty acid profiles to learn more about their energetics and feeding history. Lamprey muscle was found to be extremely rich in lipid (especially compared to salmon), and both lipid and gut fullness varied by the year of collection (2017 or 2018), lamprey size, and season. Maximum gut fullness in lamprey (>50% of body weight) far exceeded that observed for salmon. Fatty acid profiles were unique when compared to other marine fish; and this likely results from lamprey’s consumption of blood rather than muscle or whole prey. Our results suggest that the marine ecology of lamprey is surprisingly different from salmon. This study is the first analysis of lipids and fatty acids on Pacific lamprey in the marine environment and provides a baseline for future studies.

13

Session II

Tues 1:40 Exposure time of free-ranging juvenile sockeye salmon to Atlantic salmon farms in British Columbia Erin L Rechisky1, David W. Welch1, Aswea D. Porter1, Stephen Johnson2, and Scott Hinch2 1Kintama Research Services, 755 Terminal Avenue North, Nanaimo, British Columbia V9S 4K1 Canada (E-mail: erin.rechisky@kintma.com, 250-667-6951)

2 Pacific Salmon Ecology and Conservation Laboratory, Department of Forest and Conservation Sciences, University of British Columbia, 2424 Main Mall, Vancouver BC V6T 1Z4 Canada

The Discovery Islands (DI) region of British Columbia forms a major migration corridor for wild Pacific salmon. Numerous open net-pen Atlantic salmon farms located here could be a potential source of disease transfer to wild salmon, but exposure time and therefore the risk remains unquantified. In 2017 and 2018, we deployed arrays of acoustic receivers in the three major DI migration corridors to quantify route use; one of these routes (Discovery Passage) does not have salmon farms. To investigate how long wild salmon are exposed to individual salmon farms in routes that do have farms, we deployed subarrays encompassing several farms in Okisollo Channel and placed individual acoustic receivers within Atlantic salmon farm tenures. Instrumented farms were fallow in 2017 and stocked with juvenile Atlantic salmon in 2018. Juvenile sockeye salmon primarily originating from the Fraser River were captured, acoustic-tagged, and tracked through the area. Seventy-three percent of fish migrated via channels with salmon farms. In 2017, fish were detected within acoustic range of salmon farms for a median time of 4.4 min, and 12.2 min in 2018. Thus, exposure times were brief regardless of whether farms were fallow or stocked. Median travel time in Okisollo Channel where there are three farms in a 4 km stretch was 5.9 hrs in 2017 and 7.3 hours in 2018. This represented 7.1% of the total migration time through the DIs in both years therefore stocked farms did not appear to delay migration. We demonstrate that it is possible to identify migration route preference and directly measure exposure to fish farms which is critical information required to assess the risk that salmon farms may pose to wild salmon in British Columbia.

14

Tues 2:00 New Insight into the Management and Ecology of Anadromous Cutthroat Trout James P. Losee1, Andrew Claiborne1, Derek Dapp1, Riley Freeman1, Gabe Madel1, Todd Seamons1, Anna Kagley2, Jessica Miller3 , Tom Quinn4, Gustav Hellström5 and Daniel Palm5 1Washington Department of Fish and Wildlife 2National Oceanic and Atmospheric Administration 3Oregon State University 4University of Washington 5Swedish University of Agricultural Sciences Anadromous Cutthroat Trout inhabit coastal marine waters from northern California to south-central Alaska but their movement patterns, timing of spawning and seaward migration, and ocean ecology are less well known than other species of Oncorhynchus. To improve understanding of anadromous Coastal Cutthroat Trout, researchers began a multidisciplinary project to identify and fill data gaps associated with this species. PIT, acoustic, genetic and visible elastomer tags, scale analysis, and otolith microchemistry were combined with spawning ground surveys in Puget Sound, Washington to provide important insights into the biology of this species in Puget Sound. The majority of these “sea-run” Cutthroat Trout were produced by anadromous mothers, the juveniles entered marine waters at age 2, exhibited high site fidelity to nearshore beaches as juveniles and adults, and returned to natal tributaries in the spring (February through May) to spawn. In addition, we identified cutthroat trout as a new host for a marine parasitic argulid. Information regarding growth rates, migration distances, genetic stock structure marine survival and fine scale tracking will be discussed further. Together, this information provides fisheries managers with improved tools to maintain healthy populations of anadromous Cutthroat Trout across their range and may provide insight for those researching large bodied salmonids that migrate to remote, offshore feeding areas that are more difficult to monitor.

15

Tues 2:20 Something's happened: growth and survival of coho and Chinook salmon smolts in the NCC, 2000 - 2019 Brian Beckman1, Cheryl Morgan2, Meredith Journey1, Larissa Rohrbach1, Don Van Doornik3 1Northwest Fisheries Science Center, National Marine Fisheries Service, 2725 Montlake Blvd. E., Seattle, WA 98112, USA (Email: brian.beckman@noaa.gov) 2CIMRS, Hatfield Marine Science Center, Oregon State University, Newport, OR 3Manchester Field Station, Northwest Fisheries Science Center, National Marine Fisheries Service, Port Orford, WA The comparative method has long been a standard method for generating biologial inference. We have assessed growth of three groups of yearling salmon smolts from the Columbia River in the Northern California current, soon after these fish have entered marine waters. Fish sampled include interior Snake River spring Chinook and interior Upper Columbia River summer/fall Chinook salmon as well as coho salmon smolts from the lower Columbia River. We will compare and contrast patterns of growth, prey availability, ocean conditions and adult survival over two decades (2000 – 2019). Common and contrasting patterns will be identified and attributed to either common ocean conditions or differing ocean ecologies. Analysis to date suggests strong perturbations of pre-existing patterns during the marine heat wave of 2014 – 2016.

16

Tues 2:40 Correspondence between scale growth, feeding conditions, and survival of adult Chinook salmon returning to Puget Sound and Coastal Washington: implications for forecasting

Andrew M. Claiborne1, Lance Campbell, Bethany Stevick, Todd Sandell, James P. Losee, Marisa Litz, Joseph H. Anderson and Austin Anderson.

Washington Department of Fish and Wildlife, 1111 Washington St SE, Olympia WA, 98501

1Author to who correspondence should be addressed. Email: Andrew.Claiborne@dfw.wa.gov In this study, we used scale analysis of returning adults to examine the relationship between early marine growth and survival for Chinook salmon (Oncorhynchus tshawytscha) returning to the Puget Sound and coastal Washington, USA. In total, we examined scales from 2,604 individuals from 5 stocks over 7 outmigration years characterized by a range of survival conditions (range from 0.11-9.50%). We observed a positive relationship between growth during the first year at sea and survival for adults returning to Puget Sound and the Washington coast. Scale growth during the first year at sea did not co-vary between coastal Washington and Puget Sound stocks, and in most years coastal Chinook salmon attained a larger size at the end of the first year at sea. Large scale oceanographic variables (PDO, NPGO) were not significantly related to variation in scale growth, but for some Puget Sound populations, scale growth was higher in years of cooler sea surface temperatures and lower Pink salmon (O. gorbuscha) abundance. We developed a biological indicator for forecasting cohort survival of Tumwater Falls hatchery Chinook salmon on the Deschutes River, WA using marine growth estimates of the earliest returning fish (age-21). The marine growth index predicted survival better for 8 brood years compared to a recent 5 year average returns forecasting approach (3.40% vs 35.41% Mean Percent Error). Results from this study suggest that early marine growth is important to the survival of Puget Sound and coastal Washington Chinook salmon and may be a useful biological indicator to improve pre-season forecasting of Chinook salmon populations in Washington State.

17

Tues 3:20

A comparison of juvenile Chinook salmon growth in the Salish Sea and the Northern California current Meredith Journey1, Brian Beckman, Chrys Neville, Marc Trudel, Cheryl Morgan, and Don Van Doornik 1Northwest Fisheries Science Center, National Marine Fisheries Service, 2725 Montlake Blvd. E., Seattle, WA 98112, USA (Email: meredith.journey@noaa.gov) We compared growth of juvenile salmon from concurrent juvenile salmon surveys (2012-2015) of the Northern California Current survey (JSOES, NMFS) and the Strait of Georgia survey (DFO). Growth was assessed by measuring plasma concentration of insulin-like growth factor-1, or IGF-1. IGF-1 is correlated to instantaneous growth (within 3-7 days) in juvenile fishes. Samples were obtained for two years prior to the warm blob (2012 and 2013) and two years during the warm blob (2014 and 2015). In 2012 and 2013 the relationship between stock specific IGF-1 concentration and fork length were similar between the Strait of Georgia and Northern California current. In 2014 and 2015 the slope of the relationship between IGF1 concentration and fork length was more positive in the Strait of Georgia when compared to samples from the Northern California current. Preliminary analyses suggest that while surface temperatures were also warm in the Strait of Georgia in 2014 and 2015, the negative effect of the blob on growth was stronger in the Northern California current than in the Strait of Georgia.

18

Tues 3:40

The Likely Suspects Framework for Atlantic salmon: developing a multi-disciplinary approach to quantifying the drivers of marine mortality in a changing ocean environment

Colin D. Bull

Missing Salmon Alliance, Atlantic Salmon Trust, Battleby House, Redgorton, Perth, Scotland. UK

Email : colin@atlanticsalmontrust.org

The majority of Atlantic salmon management efforts are currently focused on tackling issues in freshwater, and as stock declines continue, it is clear that there is a requirement to undertake a step-change in the approach being taken to conserve this species. Coordination of the extensive research and management efforts across a range of scales is urgently required to inform our decisions, and there is a pressing need to improve our understanding of the factors influencing salmon survival in a dynamic ocean environment. In response to this need, the Likely Suspects Framework Project has been established by the Missing Salmon Alliance: a cooperative initiative amongst several UK –based salmon conservation organizations, and is receiving support from numerous other groups. Through the International Year of the Salmon initiative we are also continuing to forge strong research links with colleagues working on Pacific salmon. The basic premise of the project is to provide a focus for cooperative action, and facilitate hypothesis –led analysis of the range of factors influencing Atlantic salmon survival across the freshwater and ocean phases. It is hoped that by providing this important research focus now, and an-evidence based appraisal of the numerous factors being proposed to be influencing Atlantic salmon survival in a dynamic ocean environment, future conservation actions and approaches can be made much more effective.

Underpinning the Likely Suspects Framework is the design and implementation of a central database and data sharing platform organized around the spatial domains of Atlantic salmon. This shared resource will utilize extensive long-term environmental and biological datasets and will be used to refine an Atlantic salmon ecosystem model. The strengths of this project are in the inclusion of marine phase processes, wide stakeholder buy-in, and in the multi-disciplinary approach being adopted. Its success will be is largely dependent upon maintaining partnerships and accessing extensive environmental and biological datasets. With knowledge exchange at the heart of the process complex science outputs need to be to carefully packaged to ensure engagement and impact across the Atlantic salmon management community. Here we present an update on the initial phases of the Atlantic salmon Likely Suspects Framework project, as we establish the ecosystem model, prioritize ocean domains and progress hypotheses-testing.

19

Tues 4:00 Density-dependent marine survival of Salish Sea Chinook and coho salmon associated with pink salmon presence

Neala W. Kendall*1, Benjamin W. Nelson2, and James P. Losee1

1 Washington Department of Fish and Wildlife, 1111 Washington St. SE, Olympia, WA 98501, USA (Email: neala.kendall@dfw.wa.gov; Tel: 1-360-789-9950) 2 Institute for the Oceans and Fisheries, University of British Columbia, 2202 Main Mall, Vancouver, BC, V6T 1Z4, Canada

Understanding how species influence the population dynamics of each other is an essential part of ecosystem-based management. We analyzed 30 years of data and found that density-dependent survival of hatchery Chinook salmon released into the central and southern parts of the Salish Sea may be associated with the presence of naturally-produced pink salmon (O. gorbuscha), which are highly abundant as juveniles only in even-numbered years. We first modeled hatchery Chinook salmon marine survival as a function of the numbers of juvenile Chinook released and the presence of emigrating juvenile pink salmon between 1983 and 2012. Then we related reconstructed numbers of hatchery Chinook salmon returning to Puget Sound to the abundance of juvenile Chinook released in even (pink emigration) and odd (non-pink emigration) years from 1980 to 2010. We found that in some regions of the Salish Sea, both hatchery Chinook salmon marine survival and adult Chinook returns varied depending on the number of hatchery Chinook released and the presence of juvenile pink salmon. Specifically, in some regions survival of hatchery Chinook salmon decreased when greater numbers of juveniles were released into the Salish Sea in even years, when large numbers of pink salmon were present, but increased or remained stable when pink salmon were not present in large numbers. This suggests lower, density-dependent survival of juvenile Salish Sea Chinook salmon during even outmigration years. Our analyses suggest that scientists and managers should further investigate potential mechanisms for density-dependent survival of hatchery Chinook salmon from Salish Sea hatcheries when designing strategies to maximize adult returns. We performed similar analyses for coho salmon (O. kisutch) and also evaluated whether wild Chinook salmon productivity was associated with a pink salmon even/odd year signal, and we will discuss these results also.

20

Tues 4:20

Is “natural mortality” being underestimated? The potential impact of predation on Fraser River Chinook stocks by southern resident killer whales in their summer range

M. Bradley Hanson1, Eric J. Ward1, and Dawn P. Noren1

1National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northwest Fisheries Science Center, 2725 Montlake Blvd. E., Seattle, WA 98112, USA (brad.hanson@noaa.gov, 206-860-3220)

Recent research has highlighted the potential role that Chinook predators, in particular killer whales that specialize on Chinook, are having on these prey populations. Southern Resident killer whales (SRKW) are an endangered population in the Pacific Northwest that specializes on Chinook salmon, particularly from the Fraser River, during the summer. An individual-based bioenergetics model was developed for this population in the mid-2000s based on their stock-specific diet and residency patterns from June to September in their summer range in the San Juan Islands and western Strait of Juan de Fuca to assess the potential impact this population may have on specific Chinook stocks. We incorporated species and stock-specific caloric values for these Chinook stocks based on age, weight, and caloric content. Of the five primary Chinook stocks returning to the Fraser River, SRKWs were estimated to consume from approximately 8% to about 50% of these stocks based of the estimated total return to Canada. This is the first study to consider stock-specific predation effects of killer whales, and although some of the caveats associated with the model parameters may possibly result in over- or under-estimates of consumption, this model nonetheless illustrates that these killer whales have the potential to exert a substantially greater level of “natural mortality” on some Chinook stocks than is typically estimated by salmon managers. The recent major decrease of these whales’ residency in the San Juan Island portion of their summer range could be related to an ongoing decline of Fraser River Chinook stocks. Given the whales’ estimated relatively high predation rates on these stocks, they likely can no longer solely rely on these reduced stocks to meet their energetic needs. As a result they appear to have changed their range use to include areas where additional Chinook stocks or other species may be available.

21

Session III

Weds 10:00

Using otolith microchemistry to infer broad scale ocean migratory patterns in select Washington Chinook and coho salmon populations.

Lance A. Campbell1, Andrew M. Claiborne1, Joshua W. Chamberlin2, Wade Smith1

1Washington Department of Fish and Wildlife, Fish Program, Science Division. 1111 Washington St. Olympia, WA 98501, USA

2 National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Northwest Fisheries Science Center, 2725 Montlake Blvd. E., Seattle, WA 98112, USA

While Pacific Salmon have long been synonymous with long arduous migrations, tremendous variation occurs in nature. From non-migratory resident forms to migrations that are measured in many thousands of miles. Our understanding of salmon migration is largely informed by recapturing marked fish in fisheries and nearshore surveys. While informative, such methodologies inherently underrepresent populations that are found in low occurrence or do not overlap temporally with sampling events. Advancements in fisheries science have utilized calcified fish tissue (ie otoliths, scales, fin rays) as recording structures for biochemical markers that may prove valuable in deciphering migratory patterns independently of such mark/recapture methodology. To evaluate whether we could detect differences in otolith chemistry in stocks we presumed resided in different marine locations (Salish Sea, Coastal Wa/Or, Coastal BC/Ak); we quantified elemental composition of Chinook (Onchorynchus tshawytscha), and coho (O. kisutch ) otoliths from ocean entry to ocean annulus 1-3. We used laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) to quantify molar ratios of: Mg:Ca, Co:Ca, Cu:Ca, Mn:Ca, Zn:Ca, Sr:Ca, Ba:Ca, Pb:Ca. We found two chemical signals that may be informative of marine migratory patterns in Chinook and coho salmon. 1.) A logistic model incorporating elements: Mn:Ca, Sr:Ca, Ba:Ca found a 90% internal accuracy of assignment to coastal or Salish Sea in the first year of marine residency 2.) We found episodic patterns of higher otolith Ba:Ca during the first year of marine residency for coastal stocks and less often for stocks originating within the Salish Sea for coho and Chinook salmon. We hypothesis that the increase in Ba found during marine residency may be correlated with ocean upwelling intensity. The presence of ocean chemical markers may allow for detailed reconstruction of salmonid ocean migratory patterns. Which would provide critical information gaps for stock recovery of endangered species of salmon (stocks of Chinook, chum and steelhead) and other potentially dependent species.

22

Weds 10:40

The Global Ocean Observation System and Essential Salmon Ocean Ecology Variables Brett T. Johnson1, Ray Brunsting1, Brian Hunt2, Eric Peterson1, and Mark Saunders3

1Hakai Institute, Tula Foundation, Quadra Island Ecological Observatory, 1713 Hyacinthe Bay Rd., Heriot Bay, BC V0P 1H0 (Email: brett.johnson@hakai.org; Tel: 250-285-2628) 2Institute for the Oceans and Fisheries, University of British Columbia Vancouver, B.C., Canada V6T 1Z4 3International Year of the Salmon, North Pacific Anadromous Fisheries Commission, Suite 502, 889 West Pender Street, Vancouver, BC, Canada V6C 3B2 During a period when technological and environmental systems are changing at unprecedented rates, scientists are faced with the task of assessing and predicting the health of Earth’s ecosystems. Synoptic ecosystem surveys are conducted at great expense with the expectation that observations from different countries, habitats, and salmon life history stages will be synthesized and analyzed to produce actionable management scenarios. Despite this imperative, the implementation of information systems to integrate disparate data languishes. Salmon data are often stored in national databases according to heterogenous standards and during integration with other national data include a degree of uncertainty surrounding the interpretation and comparability of common variables. The objective of this work is to extend the Global Ocean Observation System (GOOS) by developing essential salmon ocean ecology variables and facilitate data synthesis and analysis across political and ecological domains. We must not only come to consensus on what the essential salmon ocean ecology variables are, but also define those biological measurements by adopting, implementing, and developing international metadata standards, controlled vocabularies, and semantic graph models. To ensure the technology implemented remains relevant long into the future we must adopt technologies recommended by the World Wide Web Consortium such as the Resource Description Framework or Web Ontology Language. These technologies enable data interoperability and machine reasoning using semantics which the World Wide Web makes universal. The Hakai Institute successfully developed and implemented the Canadian Integrated Ocean Observing System by working with partners across Canada and America to develop key technologies to implement the Canadian node of GOOS. This framework has been successful in defining physical and biogeochemical EOVs and is primed for extension to include biological variables through collaboration with member nations of the North Pacific Anadromous Fisheries Commission.

23

Weds 11:00

Ocean movement and behavior of steelhead revealed by pop-up satellite archival tags

Emily A. Miller1*, Andrew C. Seitz2, Michael B. Courtney3, Matthew Catterson4, Jeff Nichols4, Joseph D. Kiernan5, John O’Sullivan1, Alexander Norton1, Kyle S. Van Houtan1,6, Andre Boustany1 1Monterey Bay Aquarium, 886 Cannery Row, Monterey, CA 93940, USA, (Email: emmiller@mbayaq.org) 2University of Alaska Fairbanks, College of Fisheries and Ocean Sciences, P.O. Box 757220, Fairbanks, AK 99775, USA 3University of Alaska Fairbanks, College of Fisheries and Ocean Sciences, 17101 Point Lena Loop Road, Juneau, AK 99801, USA 4Alaska Department of Fish and Game, P.O. Box 110024, Douglas, AK 99811, USA 5NOAA Fisheries Southwest Fisheries Science Center Fisheries Ecology Division, 110 McAllister Way, Santa Cruz, CA 95060, USA 6Nicholas School of the Environment, Duke University, Box 90328, Durham, NC 27708, USA

Steelhead (Oncorhynchus mykiss) populations have declined along the southern extent of their North America range in the last century. While their freshwater life history is well-studied, their ocean ecology is largely unknown. Unlike most anadromous Pacific salmonids, steelhead are iteroparous. Gaining insights to the oceanic phase of post-spawning adults, or kelts, is therefore critical for maintenance and management of this diverse life history strategy that ensures species persistence. Conventional and acoustic tag technologies have retrieval and data collection limitations in the ocean environment. Thus, in 2018 and 2019 we tagged outmigrating female kelts with pop-up satellite archival tags (PSATs) at opposite ends of the North American range - Scott Creek, CA and Situk River, AK. Here, we report tracks from 5 CA and 16 AK tags that remained attached to steelhead for 3-172 d. Steelhead occupied an average depth of 8.6 ± 23.1 m and average temperature of 12.7 ± 1.1 °C off CA, and 2.2 ± 2.5 m and 11.0 ± 1.3 °C off AK. The farthest distance traveled by an individual kelt was over 2,600 km, from Situk River, AK to the western end of the North American Aleutian Islands and into the southern edge of the Bering Sea. We describe steelhead migratory pathways, diving behavior, and environmental preferences across regions and years. These results provide valuable first steps to understanding steelhead ocean ecology across the Pacific coast.

24

Weds 11:20

Interpreting mortality of satellite tagged salmonids

Andrew C. Seitz1, Emily A. Miller2, Michael B. Courtney3, Matthew Catterson4, Jeff Nichols4, Joseph D. Kiernan5, John O’Sullivan1, Alexander Norton1, Kyle S. Van Houtan1,6, Andre Boustany1 1University of Alaska Fairbanks, College of Fisheries and Ocean Sciences, P.O. Box 757220, Fairbanks, AK 99775, USA 2Monterey Bay Aquarium, 886 Cannery Row, Monterey, CA 93940, USA 3University of Alaska Fairbanks, College of Fisheries and Ocean Sciences, 17101 Point Lena Loop Road, Juneau, AK 99801, USA 4Alaska Department of Fish and Game, P.O. Box 110024, Douglas, AK 99811, USA 5NOAA Fisheries Southwest Fisheries Science Center Santa Cruz Laboratory, 110 McAllister Way, Santa Cruz, CA 95060, USA 6Nicholas School of the Environment, Duke University, Box 90328, Durham, NC 27708, USA Pop-up satellite archival tags (PSATs) have been successfully used to study the relatively large oceanic stage of steelhead (Oncorhynchus mykiss) and Chinook salmon (Oncorhynchus tshawytscha) in the North Pacific Ocean. In addition to behavioral data, PSATs provide valuable inference about mortality, which can be identified by suspicious patterns in ambient temperature, occupied depth and diving pattern, or light intensity data measured by the tags that do not match expectations of the study species. While some mortality events are relatively straightforward to interpret, others are much more ambiguous. Diagnostic evidence of mortality from PSAT data will be presented by comparing periods of expected behavior of steelhead and Chinook salmon to periods of suspicious behavior. Along a spectrum of straightforward-to-ambiguous to interpret data, mortality of steelhead and Chinook salmon is inferred to result from capture/tagging effects, ingestion by a variety of predators including warm-blooded fish, cold-blooded fishes, and marine mammals, and unknown causes. Although speculative, it is hypothesized that some unknown mortalities may be caused by aquatic or avian predators that kill the tagged salmonids, but do not ingest the tag. Mortality information about the relatively large oceanic stage of steelhead and Chinook salmon is important for understanding population dynamics and demographics of these species, as well as for understanding predator fields in the North Pacific Ocean.

25

Session IV

Weds 11:40

Stock-specific abundance and behaviour of mature Chinook salmon migrating off Vancouver Island

Cameron Freshwater1 and Jackie King1

1Fisheries and Oceans Canada, Pacific Biological Station, 3190 Hammond Bay Rd., Nanaimo BC V9T 6N7 (Email: Cameron.freshwater@dfo-mpo.gc.ca; Tel: 778 350-1767)

Chinook salmon from a wide range of stocks are present off the west coast of Vancouver Island (WCVI). Recently fisheries managers have been attempting to fine-tune WCVI harvest to promote the recovery of depleted populations and ensure there is sufficient aggregate abundance to sustain populations of resident killer whales, which use the region extensively. Coded wire tag (CWT) recoveries demonstrate stock-specific abundance in the region changes seasonally, suggesting some stocks are present year-round, while others only utilize the region as a migratory corridor. Although these data have been used to develop initial spatial and temporal closures, CWT recoveries do not provide sufficiently high-resolution data to estimate fine-scale survival rates or behaviors. To address these concerns, we have begun a multi-year acoustic tagging study and released 98 adult fish off the coast of WCVI in the summer of 2019. Genetic stock identification confirmed that Chinook salmon originated from most major stock aggregates south of British Columbia and we observed consistent stock-specific differences in catch distribution within the study area. Furthermore, data from 76 individuals detected by coastal Washington and Salish Sea receiver arrays suggest stock-specific differences in migration behavior. Vancouver Island, Puget Sound, and California stocks appeared to migrate relatively slowly and individuals may reside in the area for some time. Conversely, Columbia and Fraser River individuals migrated rapidly through the study area and exhibited weaker evidence of milling behaviors. Despite differences in migration rate, survival through the study area was relatively high across all aggregates. Future work will expand the duration of the tagging season and the extent of the receiver array to provide further detail on stock-specific migratory characteristics that can be used to reduce harvest impacts on stocks of concern.

26

Posters A marine salmon diet database for the North Pacific Caroline Graham1,2, Evgeny A. Pakhomov1,2 and Brian P.V. Hunt1,2,3 1Institute for Oceans and Fisheries, University of British Columbia, 2202 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada. (Email: c.graham@oceans.ubc.ca) 2Department of Earth, Ocean, and Atmospheric Sciences, University of British Columbia, 2207 Main Mall, Vancouver, British Columbia V6T 1Z4, Canada 3Hakai Institute, PO Box 25039, Campbell River, British Columbia V9W 0B7, Canada Poster Although the freshwater phase of the salmon life cycle has been studied in depth, there is much less information available on the marine phase, even though Pacific salmon can spend anywhere from 1 to 7 years of their life in the ocean. This phase of their life has also been identified as a population bottleneck. As climate change leads to warmer, rapidly changing ocean conditions, it is important to understand this phase of the salmon life cycle. It is well known that the North Pacific Ocean experiences warm and cool decadal phases, known as the Pacific Decadal Oscillation. Understanding how salmon health and survival are affected by these phases can help us to understand the future consequences of a warming climate on salmon. One of the most significant factors affecting the survival of salmon is the presence and abundance of nutritious prey. Although it is difficult to measure prey occurrence across the scale of the Pacific Ocean basin, information on prey presence and abundance can be obtained by studying salmon diets. In order to study how salmon diets change across the North Pacific under warm and cool conditions, we conducted a systematic literature review and meta-analysis using published marine diet data for all six major species of Pacific salmon. Specifically, we examined the time periods of 1959-1969 and 1987-1997, warm and cool decades, respectively. A product of this research will be an open-access database, containing available diet information that can be used as a research tool to address a variety of questions related to salmon marine survival. As changes in salmon abundance become increasingly unpredictable, it is critical to further our understanding of the ocean phase of the salmon life cycle.

27

Influences of Ecological and Anthropomorphic Processes on Survival and Growth of Auke Creek Coho Salmon

Joshua Russell1, 2, Scott Vulstek1, Megan McPhee2, Milo Adkison2, and David Tallmon3

1National Oceanic and Atmospheric Administration, National Marine Fisheries Service, Alaska Fisheries Science Center, Auke Bay Laboratory, 17109 Point Lena Loop Road, Juneau, AK 99801, USA (Email: joshua.russell@noaa.gov; Tel: 907-789-6040) 2Universiy of Alaska Fairbanks, College of Fisheries and Ocean Sciences, 17101 Point Lena Loop Road, Juneau, AK 99801, USA

3University of Alaska Southeast, Biology and Marine Biology Department, 11120 Glacier Highway, Juneau, AK 99801, USA

Poster

Coho Salmon (Oncorhynchus kisutch) are a species of great social and economic importance that are harvested for commercial, sport, personal-use, and traditional harvest. We analyzed 35 years (1980-2014) of data collected at the Auke Creek Research Station weir in Juneau, Alaska. Factors influencing Auke Creek Coho Salmon smolt production, growth, and marine survival were explored. This extensive data series allowed for an analysis of Auke Creek Coho Salmon growth and survival that is not possible elsewhere. Creek flow best explained variation in smolt-per-adult production. Analysis of freshwater and saltwater scale growth zones did not identify a specific growth period with a significant influence on marine survival. Marine survival was positively related to regional hatchery releases and the Pacific Decadal Oscillation. Changes in climate and hatchery production could have negative effects on survival of Auke Creek Coho Salmon, as evidenced by low returns in recent years associated with anomalously high temperatures in the Gulf of Alaska. Our results show that the impact of climate change and increased hatchery production should be considered in future Coho Salmon management decisions.