Understanding the processes that regulate early marine survival of salmon is a major goal of the Global Ocean Ecosystems Dynamics (GLOBEC) Northeast Pacific (NEP) program. Faster growth and larger body size are generally associated with higher marine survival for most species of juvenile salmon, which experience relatively high mortality rates during early marine life. The interaction between the temporal-spatial distribution of juvenile salmon, growth performance, environmental conditions, and stage-specific survival are critical to understanding how physical and biological factors contribute to production and survival, and influence the mechanisms, magnitude, location, and timing of marine mortality. The northern Coastal Gulf of Alaska (CGOA) is a highly productive, down-welling based system where freshwater runoff and winds dominate the physical processes on the shelf. The physical environment changes at different spatial and temporal scales, which is believed to influence inter-annual variability in distribution, feeding, growth, and survival of juvenile salmon. Pink salmon are the upper trophic level target species of GLOBEC, however, the overarching programmatic goal is to enhance our understanding of the processes driving the physical structure and biological productivity of the highly dynamic CGOA system.

Subadult and smolt behavioral data were compiled by Ali Mokdad from Trevor Pitcher's lab at the University of Windsor, Ontario, Canada. Data are comprised of fish reactions in choice flume video data (attractance/avoidance) collected by Jeremy Kraus at Tunison Lab of Aquatic Science, August 2021 and February 2020 respectively. Atlantic salmon were exposed/not exposed to imprinting chemical (morpholine) through early life stages and later tested based on their treatment to see how individuals react to the presence of exposure chemicals during subsequent life stages. These data show how the adult stage Atlantic salmon of this study ((non exposed (control) and treatment (morpholine exposed)) react to timed exposure of morpholine dilution at the 3+ and 1+ year life stages. Imprinted Atlantic salmon morphometric data were collected Feb 20, 2020 at Tunison Lab. These data represent growth (length (mm) and weight (g)) of experimental Atlantic salmon, just after imprinting flume tests were completed for their life stage/age.

This project extends and advances existing ocean distribution and size models for Chinook Salmon, a major prey of Southern Resident Killer Whales (SRKW) and target of important fisheries, to provide ocean distribution estimates for multiple run-types (fall, summer, and spring Chinook) arising from rivers from California to Alaska by season and under variable oceanic conditions. It leverages very large tag-recapture databases that have been developed for Chinook Salmon over the past 50 years – hundreds of millions of fish tagged and millions recovered – and links these recoveries to a range of fisheries in which Chinook are targeted or captured as bycatch. It integrates data coast-wide, from Alaska to California, and over more than 30 years (1978-2015), to provide a first synthetic, quantitative description of Chinook distribution that can be used to understand the total Chinook prey field available to SRKW, fishers, and other predators in different seasons and under alternate ocean states. In addition, this projects examines long-term trends in Chinook salmon size and their biological implications. Chinook populations have shown pronounced trends toward smaller and younger fish returning to spawn, and these trends have accelerated in the last 15 years. This erosion of the age-size structure and life-history diversity may negatively affect population productivity via reductions in reproductive potential, and may compromise the long-term viability of populations and jeopardize the sustainability of Chinook salmon fisheries. Consequently, long-term shifts in life-history characteristics, which are likely caused by changing ecological conditions in the ocean, might need to be accounted for when estimating reference points for fishery management. This work supports ongoing efforts to recover SRKW populations, informs the SRKW critical habitat designation process and recovery plans, feeds into the PFMC SRKW ad hoc work group, and is directly in line with the NMFS Ecosystem-Based Fisheries Management Road Map and Policy as well as the National Climate Science Strategy.

We used Adaptive Resolution Imaging Sonar (ARIS), which is based on Dual-Frequency Identification Sonar (DIDSON) technology to observe net encounter behaviors of bigheaded carps. Gill nets with four different mesh types (8.9 cm bar mesh) and trammel nets with five different mesh sizes (range 5.1-8.9 cm bar mesh) were evaluated. Net sets were undisturbed, or fish were driven with the noise of the outboard boat motor. We sampled field sites in tributaries and the mainstem Missouri River in central Missouri from June 2015 to October 2016. Specific sampling sites were determined based on previously documented Silver Carp abundance with anticipated densities sufficient for testing behavioral responses to entanglement gears. Specific tributaries sampled consisted of the Lamine River, Blackwater River, Moniteau Creek, and Cedar Creek. Habitat within these low gradient tributaries consists of minimal current if present and shallow depths (less than 4 m). Nets set in the mainstem Missouri River were downstream of channel training structures, where flow diversion resulted in minimal to no current and similar depths. Eighty net sets for 40 hours of total ARIS video were collected. Catch was used to identify length and species present in videos, with Silver Carp and Smallmouth Buffalo the predominate species caught. Within ARIS videos, body morphology was used to categorize and enumerate responses of fish.

A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River plume and Pacific Northwest coastal habitats. Adult returns vary dramatically (over 10 fold) as a result of changing (good or bad) ocean conditions juveniles experience. Evaluating the benefit of restoration efforts in the Columbia River to restore endangered salmon populations needs to consider ocean conditions as a contributing factor to recovery. This is a large collaborative project with contributions from NWFSC, Oregon State University, and Oregon Health and Science University. The work focuses on three objectives: 1) Determining the distribution, growth, and condition of juvenile Columbia River Chinook and coho salmon in the plume and their ocean environments with associated physical and biological features, and effects on salmon survival via regular spring and summer surveys. 2) Using additional focused surveys to obtain critical pieces of information on predator impacts, specific food resources, biological condition, and means by which juvenile salmon exit the Columbia River estuary. 3) Synthesizing the early ocean ecology of juvenile Columbia River Chinook and coho salmon, test mechanisms that control salmonid growth and survival, and produce ecological indices that forecast salmonid survival. This project provides critical information on marine survival to the Columbia River salmonid management community (hydrosystem, harvest, hatchery, and habitat management) provides environmental indicators useful for forecasting salmon returns, and provides a greater understanding of ecological controls on salmon populations. This is a long-term monitoring and research project initiated in 1998. Species, abundance, and distribution of birds during salmon surveys.

There is no established management protocol for stocks subject to isolation-by-distance (IBD) stock structure. This study examines several management strategies for two marine fish species subject to IBD using simulation, Pacific cod in the Aleutian Islands (AI) and northern rockfish in the Eastern Bering Sea (EBS) and Aleutian Islands. A one-dimensional stepping stone model was used to model isolation by distance, and was intended to mimic regions where marine species are exploited along a continental shelf. The performance of spatial assessment and management methods depended on how the range was split. Splitting anywhere within the managed area led to fewer demes falling below target and threshold biomass levels and higher yield than managing the entire area as a single unit. Equilibrium yield was maximized when each deme was assessed and managed separately and under catch cascading, in which harvest quotas within a management unit are spatially allocated based upon the distribution of survey biomass. The longer-lived rockfish declined more slowly than Pacific cod, and experienced greater depletion in biomass under disproportionate fishing effort due to lower productivity. Overall, splitting a management area of the size simulated in the model improved performance measures, and the optimal management strategy grouped management units by demes with similar relative fishing effort.

Pacific salmon (Oncorhynchus spp.) runs in rivers that flow into the eastern Bering Sea have been inconsistent and at times very weak. Low returns of chinook (O. tshawytscha) and chum (O. keta) salmon to the Yukon River, Kuskokwim River, and Norton Sound areas of Alaska prompted the state of Alaska to restrict commercial and subsistence fisheries during 2000 and declare the region a fisheries disaster area. Weak salmon returns to these river systems follow several years of low sockeye (O. nerka) salmon returns to Bristol Bay, which was declared a fisheries disaster region during 1998 by both the State of Alaska and the U.S. Department of Commerce. Causes of the poor salmon returns to these river systems are not known however, the regional-scale decline of these stocks indicates that the marine environment may play a critical role. Ocean conditions, particularly in the first few months after the salmon leave fresh water, are known to significantly affect salmon survival (Holtby et al. 1990; Friedland et al. 1996; Beamish and Mahnken 2001). Mechanisms affecting marine survival of the eastern Bering Sea salmon stocks are unknown, principally due to the lack of marine life history information on western Alaska salmon. To improve understanding of the marine life-history stage of salmon in the Bering Sea, the North Pacific Anadromous Fish Commission (NPAFC) began an internationally coordinated research program on salmon in the Bering Sea called the Bering-Aleutian Salmon International Survey (BASIS) (NPAFC 2001). As part of BASIS, scientists from the National Marine Fisheries Service (NMFS), Ocean Carrying Capacity (OCC) program conducted a fall survey on the eastern Bering Sea shelf to provide key ecological data for eastern Bering Sea salmon stocks during their juvenile life-history stage. The goal of the OCC/BASIS salmon research cruise was to understand mechanisms underlying the effects of environment on distribution, migration, and growth of juvenile salmon on the eastern Bering Sea shelf. Primary objectives of BASIS include: 1) to determine the extent of offshore migrations of juvenile salmon from rivers draining into the eastern Bering Sea, 2) to describe the physical environment of the eastern and northeastern Bering Sea shelf occupied by juvenile salmon, and 3) to collect biological information on other ecologically important species. Summaries of previous Bering Sea juvenile salmon research cruises can be found in Farley et al. (1999, 2000, 2001, 2002, 2004, 2005).

The primary objectives of this study are to estimate a predation rate by harbor seals on steelhead smolt in Puget Sound, and determine whether predation by harbor seals differs by region. Nisqually River steelhead will be acoustic tagged, and 12 - 18 seals will be fitted with GPS/acoustic receiver instrument packs. Tag detection capabilities will be expanded by i) monitoring harbor seals in South and Central Puget Sound and Admiralty Inlet, ii) placing stationary receivers at seal haulouts and at random locations not frequented by harbor seals, iii) conducting mobile tracking to locate tags remaining in Puget Sound after the smolt outmigration period. Seal time at depth and locations will be quantified in such a manner that estimates the amount of time seals spend at haulout locations to estimate the probability that a tag consumed by a harbor seal would be defecated near a haulout site. Data on harbor seal abundance, behavior, steelhead tag locations, and smolt abundance will be combined to estimate the predation rate and total number of smolts consumed by harbor seals. In addition, recent fish health assays indicate high infection prevalence (87-100%) and intensity (800-2500 cysts/fish) of Nanophyetus salmonica in steelhead outmigrating from Central (Green) and South (Nisqually) Puget Sound Rivers. South and Central Puget Sound steelhead populations generally experience lower early marine survival rates than those from North Puget Sound rivers, where Nanophyetus infections in assayed steelhead were absent. High infection intensity among freshwater outmigrants could contribute to rapid mortality shortly after seawater entry. This study will use acoustic telemetry to evaluate differences in the early marine survival (near river mouth to Pacific Ocean) of specific pathogen-free (SPF) and Nanophyetus-infected Puget Sound steelhead smolts. This approach will help us understand effects of Nanophyetus infection at different stages of the steelhead smolt migration through Puget Sound. Steelhead smolt locations.

PURPOSE: These data have been updated following a Canadian Science Advice Secretariat (CSAS) Regional Science Advisory Process. Associated publications are available in the citation section below or will be posted on the Fisheries and Oceans Canada (DFO) Science Advisory Schedule as they become available. Describe the total returns of large and small salmon to each Salmon Fishing Area (SFA) and to Gulf region rivers overall. DESCRIPTION: Total returns estimates of large and small salmon from SFA 15 to 18 and to Gulf region rivers as part of the stock assessment to year 2021. USE LIMITATION: To ensure scientific integrity and appropriate use of the data, we would encourage you to contact the data custodian.