Pacific Salmon

2016. Initial estimates from an integrated study examining the residence period and migration timing of juvenile sockeye salmon from the Fraser River through coastal waters of British Columbia. N. Abstract: Many stocks of Pacifi c salmon enter into and transit through the Strait of Georgia during their migration to off shore waters. Knowledge of the duration of juvenile sockeye salmon residency in the Strait of Georgia and when they migrate out of the strait is essential to understand both natural and anthropogenic factors that may be regulating their early marine survival. We present results from the fi rst year of a multi-year integrated study that demonstrates stock-specifi c diff erences in the migration timing of juvenile Fraser River sockeye salmon over the fi rst eight to 12 weeks of their marine life. The geography of the study region provides a unique opportunity to sample virtually the entire population as they migrate down the Fraser River and as they leave the Strait of Georgia through the Discovery Islands and lower Johnstone Strait. This analysis indicated that juvenile 1-year-old sockeye salmon were resident in the Strait of Georgia for seven to eight weeks in 2014. The catch rates in the Discovery Islands indicated that, in 2014, the peak migration period for Fraser River sockeye salmon occurred over approximately two weeks, with about 80% of all sockeye salmon caught between June 12 and June 19. The results suggest that the Strait of Georgia and the Discovery Islands/Johnstone Strait regions function in a similar manner as the nursery lakes and main river ways in the Fraser River watershed. The Strait of Georgia provides abundant food in a relatively protected habitat similar to their rearing lakes in the watershed. The Discovery Islands and Johnstone Strait, an area of lower food availability, is similar to the river, where fi sh move in concentrated numbers through high current fl ow areas over a relatively short period of time.

An 8-week experiment was designed to re-evaluate the arginine requirement of fingerling coho salmon. Triplicate groups of fish were fed semipurified isonitrogenous (av. protein as g amino acids/100 g dry diet=45.2) and isolipidic (av. crude lipid 11.9% dry weight) diets containing graded levels of arginine in a 6×2 factorial design with six arginine levels (expected values 3.5, 4.5, 5.5, 6.5,

Bottom-up changes in the abundance and composition of primary producers and primary consumers can cascade through ecosystems. Zooplankton stable isotopes (δ13C and δ15N) can be used to determine the linkages between these bottom-up processes, as nutrients, community composition, and physical oceanographic variables can influence zooplankton stable isotopes. However, the expression and variability in zooplankton stable isotopes remain poorly constrained and understood in many systems. Here, we explored how environmental and community variability influences zooplankton stable isotope ratios in the eastern Bering Sea across a wide range of ocean conditions. We tested whether there were interannual, spatial, or climate-driven shifts in
the δ15N and δ13C of zooplankton. We found considerable variability across the eastern Bering Sea,
with significant differences in isotopes among years, regions, and depths. These patterns were driven by differences in zooplankton community and physical oceanographic variables such as sea surface temperature. Effects were consistent across isotopes, and reflect the shared influences of oceanographic parameters and nutrients on δ13C and δ15N at the base of the food web.

Indigenous peoples often claim that colonial powers, such as settler states, violate Indigenous peoples' collective self-determination over their food systems, or food sovereignty. Violations of food sovereignty are often food injustices. Yet Indigenous peoples claim that one of the solutions to protecting food sovereignty involves the conservation of particular foods, from salmon to wild rice. This essay advances an argument that claims of this kind set forth particular theories of food sovereignty and food injustice that are not actually grounded in a static conception of Indigenous culture; instead, such claims offer important contributions to how settler colonial domination is understood as a form of injustice affecting key relationships that support Indigenous collective self-determination through food sovereignty. The essay describes some of the significant qualities of reciprocal relationships that support food sovereignty, referring widely to the work of Indigenous leaders and scholars and Tribal staff on salmon conservation in North America.

Whyte, K.P. 2018. Food Sovereignty, Justice and Indigenous Peoples: An Essay on Settler Colonialism and Collective Continuance. Oxford Handbook on Food Ethics. Edited by A. Barnhill, T. Doggett, and A. Egan, 345-366. Oxford University Press.

This thesis focuses on the ways in which people cultivate relations with salmon along the Kuskokwim River in Southwest Alaska. It examines conservation narratives which develop around a decreasing salmon population and analyses the different ascriptions of agency which are attributed to them. This work places human-animal relationships at the centre between State salmon conservation strategies and Yup’ik subsistence fishing, in particular after intensified conservation efforts and restrictions of king salmon harvest in the area. I argue that both subsistence harvesting and salmon management establish ways of knowing these animals, relations of care, and perceptions of environmental shifts, but emerge as incommensurable in moments of crisis. Combined with an understanding of the post-colonial structures in which salmon management is embedded, the research analyses how the ontological tensions of relations between people and fish are too strong to be mediated in co-management approaches and even court hearings. Yet, although conflicting, these relations co-exist most of the time. To understand how these relations are maintained, negotiated, and perpetuated, this thesis gives detailed ethnographic analyses of settings in which they take place. This includes management offices, fishing boats, fish camps, and weirs, and furthermore includes tools like nets and knives which help to understand the role of salmon in social lives in Bethel and the Yukon-Kuskokwim Delta. My work tells stories in which salmon cannot be mastered or controlled but become an indicator for the well-being of human relationships with each other, salmon, and their shared environment.

were found to produce otolith daily increments, as well as a consistently visible marine-entry check formed during their transition to salt water. Field-collected O. nerka post-smolts of an equivalent age also displayed visible checks; however, microchemistry estimates of marine-entry date using Sr:Ca ratios differed from visual estimates by c. 9 days suggesting that microstructural and microchemical processes occur on different time scales.

Of the many technologies used by the Canadian Salmonid Enhancement Program (SEP, established in 1979), hatcheries have been a major tool used to increase the freshwater survival of selected wild, native stocks of coho, chinook and chum salmon, both to address conservation concerns and to provide fishing opportunities. SEP hatcheries have contributed substantially to the fisheries for coho and chum

The territories of the Tsimshian speaking peoples (Coast Tsimshian, Kitselas, Gitksan and Nisga'a ) are rich in petroglyphs. Many are located at the mouths  and canyons of salmon rivers. Oral histories document their use by fishing shamen to attract the fish into their economic areas.

There remains a near pervasive delusion that wild salmon in California, Oregon, Washington, and Idaho could be greatly increased concurrent with the present upward trajectory of the region’s human population coupled with most individuals’ apparent unwillingness to reduce substantially their consumption of resources and standard of living.  Few salmon advocates argue publicly that society must make these substantial and contentious changes to recover wild salmon.  Further, the implicit public optimism of salmon scientists and technocrats about restoring wild salmon tends to perpetuate this avoidance of reality.  At least some of this delusional reality is validated by salmon technocrats being influenced by funding provided through salmon recovery programs.

This study presents isotopic data (d13C and d15N from bone collagen) for 104 samples representing 29 vertebrate taxa from late pre-contact through to contact era (ca. 2000 – 100 BP) Haida Gwaii (British Columbia, Canada) from a wide variety of mostly marine organisms. The results demonstrate the considerable isotopic variability that characterizes potential prey items in coastal contexts and underscores the need for baseline faunal data to interpret human subsistence practices. Based on these data, a detailed marine food web was constructed, which provides insight into local ecological conditions. We present a simple method for quantifying the trophic level of ancient fauna using d15N of bone collagen. Finally, we discuss the implications of this study for the reconstruction of human diet.

Infectious diseases are potential contributors to decline in Coho salmon (Oncorhynchus kisutch) populations. Although pathogens are theoretically considered to pose higher risk in high-density rearing environments like hatcheries, there is no direct evidence that hatchery-origin Coho salmon increase the transmission of infectious agents to sympatric wild populations. This study was undertaken to compare prevalence, burden, and diversity of infectious agents between hatchery-reared and wild juvenile Coho salmon in British Columbia (BC), Canada. In total, 2,655 juvenile Coho salmon were collected between 2008 and 2018 from four regions of freshwater and saltwater in BC. High-throughput microfluidics qPCR was employed for simultaneous detection of 36 infectious agents from mixed-tissue samples (gill, brain, heart, liver, and kidney). Thirty-one agents were detected at least once, including ten with prevalence >5%. Candidatus Brachiomonas cysticola, Paraneuclospora theridion, and Parvicapsula pseudobranchiocola were the most prevalent agents. Diversity and burden of infectious agents were substantially higher in marine environment than in freshwater. In Mainland BC, infectious burden and diversity were significantly lower in hatchery smolts than in wild counterparts, whereas in other regions, there were no significant differences. Observed differences in freshwater were predominantly driven by three parasites, Loma sal-monae, Myxobolus arcticus, and Parvicapsula kabatai. In saltwater, there were no consistent differences in agent prevalence between hatchery and wild fish shared among the west and east coasts of Vancouver Island. Although some agents showed differential infectious patterns between regions, annual variations likely contributed to this signal. Our findings do not support the hypothesis that hatchery smolts carry higher burdens of infectious agents than conspecific wild fish, reducing the potential risk of transfer to wild smolts at this life stage. Moreover, we provide a baseline of infectious agents in juvenile Coho salmon that will be used in future research and modeling potential correlations between infectious profiles and marine survival. PLOS ONE | https://doi.org/10.1371/journal.pone.

The loss of genetic and life history diversity has been documented across many taxonomic groups, and is considered a leading cause of increased extinction risk. Juvenile salmon leave their natal rivers at different sizes, ages and times of the year, and it is thought that this life history variation contributes to their population sustainability, and is thus central to many recovery efforts. However, in order to preserve and restore diversity in life history traits, it is necessary to first understand how environmental factors affect their expression and success. We used otolith 87Sr/86Sr in adult Chinook salmon (Oncorhynchus tshawytcha) returning to the Stanislaus River in the California Central Valley (USA) to reconstruct the sizes at which they outmigrated as juveniles in a wetter (2000) and drier (2003) year. We compared rotary screw trap-derived estimates of outmigrant timing, abundance and size with those reconstructed in the adults from the same cohort. This allowed us to estimate the relative survival and contribution of migratory phenotypes (fry, parr, smolts) to the adult spawning population under different flow regimes. Juvenile abundance and outmigration behavior varied with hydroclimatic regime, while downstream survival appeared to be driven by size- and time-selective mortality. Although fry survival is generally assumed to be negligible in this system, >20% of the adult spawners from outmigration year 2000 had outmigrated as fry. In both years, all three phenotypes contributed to the spawning population, however their relative proportions differed, reflecting greater fry contributions in the wetter year (23% vs. 10%) and greater smolt contributions in the drier year (13% vs. 44%). These data demonstrate that the expression and success of migratory phenotypes vary with hydrologic regime, emphasizing the importance of maintaining diversity in a changing climate.