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ABSTRACT ObjectiveApex-predator-initiated trophic cascades occur in many nearshore marine habitats that simultaneously serve as critical habitat and food sources for commercially and ecologically important species, including juvenile Pacific salmon Oncorhynchus spp. Yet the potential relationships among apex predators (e.g., sea otters Enhydra lutris), submerged aquatic vegetation, and juvenile salmonids are not well understood. In Southeast Alaska, we investigated (1) juvenile salmonid abundance in eelgrass Zostera marina meadows and understory kelp beds and (2) potential drivers of juvenile Chum Salmon Oncorhynchus keta and Pink Salmon O. gorbuscha abundance in eelgrass meadows. MethodsWe analyzed historic (1998–2007) beach seine surveys to compare juvenile salmonid abundance in nearshore habitats. We then employed the same survey (2017, 2019) in eelgrass to quantify juvenile salmonid abundance alongside the influence of sea otter density (number/km2), distance from anadromous stream (km), seasonality, sediment categorization, and aboveground eelgrass biomass (g/m2). ResultsWe found greater abundance of Chum Salmon in understory kelp compared with eelgrass, whereas Pink Salmon abundance was similar between habitats. In eelgrass, Chum Salmon abundance peaked in June and was positively associated with sea otter density. Pink Salmon abundance varied seasonally, peaking in May. We found increased Pink Salmon abundance with increasing sea otter density and distance from anadromous stream and decreased abundance with increased eelgrass biomass. ConclusionGrowth and survival while juvenile salmonids are out-migrating from streams and relying on nearshore vegetated habitats can determine if they recruit to fisheries as adults. Here, we highlight the use of multiple habitats, eelgrass and understory kelp, indicating that both should be explored as critical nursery habitat. We present evidence of indirect effects of sea otters influencing the abundance of juvenile salmonids, with potential further implications as sea otter populations expand. Apex predators, quality of vegetated habitats, and their structuring roles in the nearshore are critical for informing adaptive coastal fisheries management. 

Abstract Arctic Indigenous food systems are essential to the survival of local communities, but face significant challenges due to environmental, economic, and social pressures. The objective of this study is to elicit values of the mixed Indigenous food system on St. Paul Island, Alaska, and understand their potential as deep leverage points for transformative change in the context of their historical co-evolution with the local food system. To achieve this objective, we engage three generational groups within the Aleut Community of St. Paul Island to obtain local food system stories. From these stories, we (i) elicit historical events that are thought to have shaped the local food system, (ii) identify factors that influence the food system in its present and future states, and (iii) delineate intrinsic, instrumental, and relational food system values. Our findings show that most identified historical events are perceived to have undermined the Indigenous food system and that most factors identified to shape present and future food system states present barriers for community members to engage in traditional practices. Yet, despite this, values that relate to traditional Indigenous livelihoods remain central in the local value system. These results suggest a value change debt, i.e., a time lag between changes in peoples’ held values following changes in the system around them. We propose that this lag provides a window of opportunity to leverage transformative change. We argue that as long as traditional food system values persist, there is potential to reconfigure the food system in a way that embraces these values, enhancing the system's relevance to the community's way of life. 

ABSTRACT In this research, we bridge knowledge systems and perspectives from Indigenous and rural fishers alongside state and federal managers and biologists regarding the state of salmon management and research processes in the Kuskokwim Region of southwestern Alaska. The key objectives were to identify strategies to improve salmon management, document perspectives on Alaska Native inclusion in current management and research processes, and illustrate ways to develop more inclusive management processes and organizations. We also identify key opportunities and barriers to relationship building between Tribes and management agencies. Lastly, we explore perceptions of equity and equality and how research and management account for these dimensions. This was a two‐component research project, with one component being primarily Indigenous‐led and community‐engaged, and the second component involving agency management and research staff. We carried out 28 semi‐directed interviews with 45 Indigenous and community knowledge holders across five different communities from June 2019 to May 2022, in addition to 12 interviews with state and federal managers and researchers in 2023. Our study revealed both key differences and shared understandings between state, federal, and community perspectives regarding salmon management and research and around agency inclusion of Indigenous Knowledge systems and Tribal governments. Shared visions and solutions for improving salmon management in southwestern Alaska and elsewhere reflect a greater need for community and Indigenous empowerment and inclusion in fisheries management and research, in addition to increased relationship building and agency time spent in communities. A key recommendation arising from this study is that trust and respect are precursors to meaningfully bridging knowledge systems. Our team encourages further investigation of current power and resource disparities that prohibit equitable knowledge sharing in fisheries management and research, while identifying broad solutions for improving the current salmon management system given diverse sharing across Indigenous, federal, and state experts. 

ABSTRACT We examine the coloniality of Alaska pollock (Walleye Pollock Gadus chalcogrammus) trawl fisheries governance and its role in enabling salmon bycatch, highlighting the resulting impacts on Alaska Native communities and subsistence practices. We expose how the systemic marginalization of Alaska Native voices and knowledge in federal fisheries management perpetuates dispossession, oppression, and is a barrier to food sovereignty and environmental justice. Alaska Native communities have long attributed the decline of salmon populations, particularly Chinook Salmon Oncorhynchus tshawytscha and Chum Salmon O. keta, to bycatch from the pollock trawl fishery—a concern ignored for over a decade. The repeated failure to meet salmon escapement goals has led to subsistence and commercial fishery closures, deepening food insecurity, health crises, and cultural disruption for Alaska Native peoples. Meanwhile, industrial trawl fisheries persist with minimal accountability, exacerbating ecological harm by capturing nontarget species, such as salmon, halibut, and crab, further impacting local, nonindustrial fisheries. We advocate for urgent reform of Alaska’s federal fisheries governance to center Alaska Native voices, integrate Indigenous knowledge, and address inequities in salmon allocation. Specifically, we call for revisions to the national standards of the Magnuson–Stevens Fishery Conservation and Management Act to ensure policies that respect Native sovereignty, promote sustainability, and mitigate the ecological and social consequences of industrial trawling. This approach is critical to achieving equitable and sustainable fisheries management that upholds environmental justice and Alaska Native rights. 

ABSTRACT Maladapted immigrants may reduce wild population productivity and resilience, depending on the degree of fitness mismatch between dispersers and locals. Thus, domesticated individuals escaping into wild populations is a key conservation concern. In Prince William Sound, Alaska, over 700 million pink salmon (Oncorhynchus gorbuscha) are released annually from hatcheries, providing a natural experiment to characterize the mechanisms underlying impacts to wild populations. Using a dataset of > 200,000 pink salmon sampled from 30 populations over 8 years, we detected significant body size and phenological differences between hatchery‐ and wild‐origin spawners, likely driven by competitive differences during maturation and broodstock selection practices. Variation in traits was reduced in hatchery fish, raising biodiversity concerns. However, phenotypic traits of immigrants and locals were positively correlated. We discuss possible mechanisms that may explain this pattern and how it may reduce adverse impacts associated with reduced trait variation. This study suggests that domestication impacts are likely widespread, but local adaptation may be maintained by phenotypic sorting. 

Abstract BackgroundIn recent years public health research has shifted to more strengths or asset-based approaches to health research but there is little understanding of what this concept means to Indigenous researchers. Therefore our purpose was to define an Indigenous strengths-based approach to health and well-being research. MethodsUsing Group Concept Mapping, Indigenous health researchers (N = 27) participated in three-phases. Phase 1: Participants provided 218 unique responses to the focus prompt “Indigenous Strengths-Based Health and Wellness Research…” Redundancies and irrelevant statements were removed using content analysis, resulting in a final set of 94 statements. Phase 2: Participants sorted statements into groupings and named these groupings. Participants rated each statement based on importance using a 4-point scale. Hierarchical cluster analysis was used to create clusters based on how statements were grouped by participants. Phase 3: Two virtual meetings were held to share and invite researchers to collaboratively interpret results. ResultsA six-cluster map representing the meaning of Indigenous strengths-based health and wellness research was created. Results of mean rating analysis showed all six clusters were rated on average as moderately important. ConclusionsThe definition of Indigenous strengths-based health research, created through collaboration with leading AI/AN health researchers, centers Indigenous knowledges and cultures while shifting the research narrative from one of illness to one of flourishing and relationality. This framework offers actionable steps to researchers, public health practitioners, funders, and institutions to promote relational, strengths-based research that has the potential to promote Indigenous health and wellness at individual, family, community, and population levels. 

ABSTRACT Warming associated with climate change is driving poleward shifts in the marine habitat of anadromous Pacific salmon (Oncorhynchusspp.). Yet the spawning locations for salmon to establish self‐sustaining populations and the consequences for the ecosystem if they should do so are unclear. Here, we explore the role of temperature‐dependent incubation survival and developmental phenology of coho salmon (Oncorhynchus kisutch) as a potential early life history barrier to establishment in an Arctic stream. We exposed embryos to temperatures previously recorded in the substrate of an Arctic groundwater spring‐fed spawning environment. Using a common garden experimental design, coho salmon embryos were exposed to treatments that thermally mimicked four spawning dates from August 1 to October 1 (AUG1, SEPT1, SEPT15, and OCT1). Spawning temperatures were 6°C at the warmest (AUG1) and 1.25°C at the coldest (OCT1). We observed low survival rates in SEPT1 (41%) and OCT1 (34%) and near complete mortality in the other treatments. While far below what is considered normal in benign hatchery‐like conditions, these rates suggest that temperatures experienced at these spawning dates are survivable. We detected differences in developmental rates across treatments; embryos developed 1.9 times faster in the warmest treatment (AUG1, 120 days) compared to the coldest (OCT1, 231 days). Differences in accumulated thermal units (ATUs) needed for hatching ranged from 392 ATUs in AUG1 to 270 ATUs in OCT1, revealing compensation in developmental requirements. Given these findings, the most thermally suitable spawning dates within our study are between September 15 and October 1, which facilitates hatching and projected nest emergence to occur in spring warming conditions (March–September). Broadly, our findings suggest that spawning sites within thermal tolerances that can support the survival and development of coho salmon exist in the North American Arctic. Whether the habitat is otherwise suitable for transitions through other life stages remains unknown. 

Abstract Disease is a key driver of community and ecosystem structure, especially when it strikes foundation species. In the widespread marine foundation species eelgrass (Zostera marina), outbreaks of wasting disease have caused large‐scale meadow collapse in the past, and the causative pathogen,Labyrinthula zosterae, is commonly found in meadows globally. Research to date has mainly focused on abiotic environmental drivers of seagrass wasting disease, but there is strong evidence from other systems that biotic interactions such as herbivory can facilitate plant diseases. How biotic interactions influence seagrass wasting disease in the field is unknown but is potentially important for understanding dynamics of this globally valuable and declining habitat. Here, we investigated links between epifaunal grazers and seagrass wasting disease using a latitudinal field study across 32 eelgrass meadows distributed from southeastern Alaska to southern California. From 2019 to 2021, we conducted annual surveys to assess eelgrass shoot density, morphology, epifauna community, and the prevalence and lesion area of wasting disease infections. We integrated field data with satellite measurements of sea surface temperature and used structural equation modeling to test the magnitude and direction of possible drivers of wasting disease. Our results show that grazing by small invertebrates was associated with a 29% increase in prevalence of wasting disease infections and that both the prevalence and lesion area of disease increased with total epifauna abundances. Furthermore, these relationships differed among taxa; disease levels increased with snail (Lacunaspp.) and idoteid isopod abundances but were not related to abundance of ampithoid amphipods. This field study across 23° of latitude suggests a prominent role for invertebrate consumers in facilitating disease outbreaks with potentially large impacts on coastal seagrass ecosystems. 

Abstract Disentangling the influences of climate change from other stressors affecting the population dynamics of aquatic species is particularly pressing for northern latitude ecosystems, where climate‐driven warming is occurring faster than the global average. Chinook salmon (Oncorhynchus tshawytscha) in the Yukon‐Kuskokwim (YK) region occupy the northern extent of their species' range and are experiencing prolonged declines in abundance resulting in fisheries closures and impacts to the well‐being of Indigenous people and local communities. These declines have been associated with physical (e.g., temperature, streamflow) and biological (e.g., body size, competition) conditions, but uncertainty remains about the relative influence of these drivers on productivity across populations and how salmon–environment relationships vary across watersheds. To fill these knowledge gaps, we estimated the effects of marine and freshwater environmental indicators, body size, and indices of competition, on the productivity (adult returns‐per‐spawner) of 26 Chinook salmon populations in the YK region using a Bayesian hierarchical stock‐recruitment model. Across most populations, productivity declined with smaller spawner body size and sea surface temperatures that were colder in the winter and warmer in the summer during the first year at sea. Decreased productivity was also associated with above average fall maximum daily streamflow, increased sea ice cover prior to juvenile outmigration, and abundance of marine competitors, but the strength of these effects varied among populations. Maximum daily stream temperature during spawning migration had a nonlinear relationship with productivity, with reduced productivity in years when temperatures exceeded thresholds in main stem rivers. These results demonstrate for the first time that well‐documented declines in body size of YK Chinook salmon were associated with declining population productivity, while taking climate into account. 

Abstract ObjectiveIn a southcentral Alaska stream system, we conducted a study to evaluate the effect of trap type (galvanized and nylon coated), bait type (salmon roe cured with and without sodium sulfite), and soak times (1 h and 24 h) on captures of juvenile salmon using Gee-style minnow traps. This was undertaken due to the limited research on this topic, aiming to determine how variations in methodology affected captures in juvenile salmon. MethodsWe employed a three-way fixed factorial design to sample 176 stream reaches (with a single trap in each each) from June 2021 to September 2021, capturing 296 Coho Salmon Oncorhynchus kisutch and 105 Chinook Salmon O. tshawytscha. ResultWe found an estimated 78% decrease in captures of Coho Salmon when nylon-coated traps were used instead of galvanized traps, and we found that trap type showed no effect on number of captures for Chinook Salmon. Additionally, we did not detect effects of bait type and soak time on the number of captures for either species. Not surprisingly, there was a positive relationship between Julian date and temperature with captures for both species. Additionally, for Coho Salmon, we found a quadratic relationship between water velocity and captures. ConclusionUnderstanding and accounting for these factors will help researchers to maximize trapping efficiency, standardize protocols, and determine the extent to which results are comparable across studies employing different methods.