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The immense challenges associated with realizing ocean and coastal sustainability require highly skilled interdisciplinary marine scientists. However, the barriers experienced by early career researchers (ECRs) seeking to address these challenges, and the support required to overcome those barriers, are not well understood. This study examines the perspectives of ECRs on opportunities to build interdisciplinary research capacity in marine science. We engaged 23 current and former graduate students and postdoctoral fellows in a policy Delphi method with three rounds of surveying that included semi-structured questionnaires and q-methodology. We identified the following five barriers that limit ECRs’ capacity for interdisciplinary research: (i) demanding workloads; (ii) stress linked to funding, publishing, and employment uncertainty; (iii) limited support for balancing personal and professional commitments; (iv) ineffective supervisory support; and (v) the steep learning curve associated with interdisciplinary research. Our analysis highlights three main types of responses to these barriers adopted by ECRs, including “taking on too much”, “coping effectively”, and “maintaining material wellbeing at any cost”. To overcome these barriers, we propose the following three institutional actions to build early career interdisciplinary researcher capacity: formalize mentorship, create interdisciplinary research groups, and mainstream mental health support.

Marine protected areas are advocated as a key strategy for simultaneously protecting marine biodiversity and supporting coastal livelihoods, but their implementation can be challenging for numerous reasons, including perceived negative effects on human well-being. We synthesized research from 118 peer-reviewed articles that analyse outcomes related to marine protected areas on people, and found that half of documented well-being outcomes were positive and about one-third were negative. No-take, well-enforced and old marine protected areas had positive human well-being outcomes, which aligns with most findings from ecological studies. Marine protected areas with single zones had more positive effects on human well-being than areas with multiple zones. Most studies focused on economic and governance aspects of well-being, leaving social, health and cultural domains understudied. Well-being outcomes arose from direct effects of marine protected area governance processes or management actions and from indirect effects mediated by changes in the ecosystem. Our findings illustrate that both human well-being and biodiversity conservation can be improved through marine protected areas, yet negative impacts commonly co-occur with benefits. While marine protected areas are key for supporting biodiversity and coastal communities, the outcomes can be, and can be perceived, as a mixed bag. Synthesizing research from 118 articles, this Analysis draws broad insights about both the effects of marine protected areas as well as which aspects remain understudied.

Pacific salmon encounter widely varying environmental conditions across populations. Performance traits and environmental tolerance limits are predicted to be related to the typical abiotic and biotic conditions encountered by each population. Endurance swim performance at three different temperatures (8, 12, 22 °C) was compared across nine populations of sockeye salmon (Oncorhynchus nerka (Walbaum, 1792)) parr from British Columbia, Canada, reared in a common laboratory environment. In addition, relative ventricular mass (RVM) was compared between good and poor performers from each population. Populations significantly differed in endurance swim performance and these differences were related to the natal lake environment. Specifically, parr populations that reside in warm, shallow lakes (Okanagan, Scotch, and Stellako) had superior swim performance at 12 °C compared with 8 °C. All other populations from deeper, cooler lakes had equivalent swim performance at 8 and 12 °C. Individual variability in swim performance within a population was not due to differences in cardiac size. Similarly, RVM did not vary across parr populations, suggesting that population differences in swim performance were not associated with cardiac size. This study provides further support that sockeye salmon parr are locally adapted to their environmental conditions.

Voluntary measures may be an alternative or addition to legislation for marine protected areas (MPAs), yet the effectiveness of these measures is rarely analyzed. The application and effectiveness of voluntary measures was reviewed for MPA management in developed nations where complex jurisdictions and legislative processes make voluntary measures appealing to management. Four types of voluntary measures were identified: sacrifice of access, sector- or activity-specific restrictions, voluntary stewardship, and education or outreach, with sector- or activity-specific measures being the most common. Very few papers (only 20 of 144) provided thorough assessments of outcomes or effectiveness of voluntary measures; of these, less than a quarter pointed to successful outcomes in connection with voluntary measures for MPAs or marine conservation more broadly, while half indicated mixed or uncertain results. The main factor to which failure of voluntary measures was attributed was the lack of leverage to discourage non-compliance. Key factors for the success of voluntary measures included community support, cohesive user organizations, and good governance (i.e., leadership, financing, a perception of fairness). To improve efficacy of voluntary measures for MPAs, empirical research is needed to establish effective circumstances where, when, and how voluntary measures can be applied to address management objectives.

Because of the complexity and speed of environmental, climatic, and socio-political change in coastal marine social-ecological systems, there is significant academic and applied interest in assessing and fostering the adaptive capacity of coastal communities. Adaptive capacity refers to the latent ability of a system to respond proactively and positively to stressors or opportunities. A variety of qualitative, quantitative, and participatory approaches have been developed and applied to understand and assess adaptive capacity, each with different benefits, drawbacks, insights, and implications. Drawing on case studies of coastal communities from around the globe, we describe and compare 11 approaches that are often used to study adaptive capacity of social and ecological systems in the face of social, environmental, and climatic change. We synthesize lessons from a series of case studies to present important considerations to frame research and to choose an assessment approach, key challenges to analyze adaptive capacity in linked social-ecological systems, and good practices to link results to action to foster adaptive capacity. We suggest that more attention be given to integrated social-ecological assessments and that greater effort be placed on evaluation and monitoring of adaptive capacity over time and across scales. Overall, although sustainability science holds a promise of providing solutions to real world problems, we found that too few assessments seem to lead to tangible outcomes or actions to foster adaptive capacity in social-ecological systems.

Predicting the future impact of changing thermal regimes on life history stages for wild fish requires a better understanding of the relative importance of population origin and offspring size on embryonic development. We assessed hatch timing and offspring size of Sockeye Salmon Oncorhynchus nerka in relation to egg size (variation from full-sibling families), population origin, and temperature (three treatments of 10, 14, and 16°C). Both hatch timing and hatch duration varied by the interacting effects of population origin and thermal treatment, shown in crossing reaction norms. Hatching was faster, yet more variable, at higher temperatures across many groups, so while fish generally hatched faster, developmental asynchrony also increased among families. On average, fish incubated at 16°C were shorter but not lighter at hatch, showing developmental tradeoffs between basal metabolic requirements and growth. Egg size decreased among populations as migratory distance increased, but development rate...

Climate change poses novel and complex challenges to planning, management, and policies for marine and coastal social-ecological systems. Despite ongoing discussion of adopting interventions for improving adaptation and adaptive capacity to climate change, practitioners often continue to carry out conventional management strategies that do not effectively incorporate climate change impacts and projections. Using a web-based survey and semi-structured interviews, we explored the perceptions of practitioners (coastal managers and planners) in British Columbia, Canada relative to climate change risks, adaptation actions for social and ecological systems, and barriers for adaptation within the region. Overall, practitioners shared a concern that climate change is not currently well incorporated in management or policy in this region, and noted significant implementation gaps. Practitioners expressed more support for ecological adaptation actions that are well suited to regional implementation, such as incorporating climate change projections into management and reducing fisheries overexploitation, than for actions such as protecting specific areas. Social adaptation actions were overall perceived as less useful than ecological adaptation actions, and actions that would support local management and monitoring efforts were viewed as more useful than developing alternative livelihoods. The main barriers and associated opportunities for climate change adaptation in marine management included political action, reducing scientific uncertainty, improving communication, and increasing capacity (both funding and staff). Additional opportunities include effective engagement with Indigenous governance, improving policies and funding for adaptation including monitoring, and focusing efforts on communication and education programs specific to practitioners and communities. This study demonstrates the necessity of collaboration across scales of management for effective climate change adaptation.

Using a fixed-speed test, burst swimming performance was found to vary among nine populations of emergent sockeye salmon Oncorhynchus nerka fry reared in a common-garden environment. No consistent relationship was, however, detected between difficulty of fry migration (upstream v. downstream) to rearing areas and total burst swimming duration or bursting rate.

In order to reverse the decline of imperilled species, we need to know what is threatening their survival. Canada’s Species at Risk Act (SARA) is intended to provide for the protection and recovery of species listed under the Act. Threats to SARA-listed species must be documented in recovery strategies, which also define recovery goals and critical habitat. We reviewed finalized recovery strategies for 146 species to determine the major threats to these species and whether designation of critical habitat or the relative ambition of recovery goals is associated with the nature of threats. We then compared our findings to the threats described in reports prepared by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC), the independent body which prepares status reports for all imperilled species (including those not listed under SARA). Human disturbance, in particular due to recreation, was the most frequently listed threat in recovery strategies, followed by invasive species and residential and commercial development. Threats differed among taxonomic groups and broad habitat types, but there was no evidence that low ambition of recovery goals or failure to designate critical habitat were correlated with particular threats. However, species with certain threats, including biological resource use, were less likely either to be listed under SARA and/or to have a finalized recovery strategy once listed. Documenting threat-based differences in the recovery process is an important first step toward ensuring that SARA results in timely and effective measures to recover all listed species.

Differences in thermal tolerance during embryonic development in Fraser River sockeye salmon Oncorhynchus nerka were examined among nine populations in a controlled common-garden incubation experiment. Forcing embryonic development at an extreme temperature (relative to current values) of 16° C, representing a future climate change scenario, significantly reduced survival compared to the more ecologically moderate temperature of 10° C (55% v. 93%). Survival at 14° C was intermediate between the other two temperatures (85%). More importantly, this survival response varied by provenance within and between temperature treatments. Thermal reaction norms showed an interacting response of genotype and environment (temperature), suggesting that populations of O. nerka may have adapted differentially to elevated temperatures during incubation and early development. Moreover, populations that historically experience warmer incubation temperatures at early development displayed a higher tolerance for warm temperatures. In contrast, thermal tolerance does not appear to transcend life stages as adult migration temperatures were not related to embryo thermal tolerance. The intra-population variation implies potential for thermal tolerance at the species level. The differential inter-population variation in thermal tolerance that was observed suggests, however, limited adaptive potential to thermal shifts for some populations. This infers that the intergenerational effects of increasing water temperatures may affect populations differentially, and that such thermally mediated adaptive selection may drive population, and therefore species, persistence.

We compared exhaustion-related physiological stress and physical injury as contributors to fish condition, longevity, and egg retention in two Pacific salmon species after their arrival at spawning areas. Adult female Pink Salmon Oncorhynchus gorbuscha and Chum Salmon O. keta were exposed to six experimental capture treatments that represented different levels of exhaustive exercise, air exposure, and injury. After we evaluated its reflex impairment and obtained a blood sample, each fish was released into its natal spawning channel with an external tag and later retrieved postmortem to evaluate spawning success via examining egg retention. Reflex impairment, plasma lactate, chloride, potassium, and osmolality varied among treatments, with differences generally driven by the length of exposure to capture stress, which included exhaustive exercise and air exposure. However, overall prespawn mortality was negligible (about 5%) and consistent across treatments for both species. We hypothesize that Pi...

Global drivers of change are affecting marine ecosystems and the people who depend on them at increasing rates and severities. Yet most marine conservation actions were developed before climate change was widely recognized as a major driver of change. In this chapter, we synthesize categories of marine conservation actions and their relevance at local and global scales, discuss linkages between scales, identify existing gaps, and provide recommendations. Marine conservation actions include those that directly address threats (protection, species management, and habitat management), and those that support, enable, or facilitate direct actions (law and policy; education and awareness; livelihood, economic and other incentives; and external capacity building). Our review reveals that although many effective marine conservation actions exist, all can be implemented more broadly and at multiple scales. Linking scales will be increasingly required to effectively address global drivers of change in the Anthropocene.

This paper synthesizes tagging studies to highlight the current state of knowledge concerning the behaviour and survival of anadromous salmonids in the marine environment. Scientific literature was reviewed to quantify the number and type of studies that have investigated behaviour and survival of anadromous forms of Pacific salmon (Oncorhynchus spp.), Atlantic salmon (Salmo salar), brown trout (Salmo trutta), steelhead (Oncorhynchus mykiss), and cutthroat trout (Oncorhynchus clarkii). We examined three categories of tags including electronic (e.g. acoustic, radio, archival), passive (e.g. external marks, Carlin, coded wire, passive integrated transponder [PIT]), and biological (e.g. otolith, genetic, scale, parasites). Based on 207 papers, survival rates and behaviour in marine environments were found to be extremely variable spatially and temporally, with some of the most influential factors being temperature, population, physiological state, and fish size. Salmonids at all life stages were consistently found to swim at an average speed of approximately one body length per second, which likely corresponds with the speed at which transport costs are minimal. We found that there is relatively little research conducted on open-ocean migrating salmonids, and some species (e.g. masu [O. masou] and amago [O. rhodurus]) are underrepresented in the literature. The most common forms of tagging used across life stages were various forms of external tags, coded wire tags, and acoustic tags, however, the majority of studies did not measure tagging/handling effects on the fish, tag loss/failure, or tag detection probabilities when estimating survival. Through the interdisciplinary application of existing and novel technologies, future research examining the behaviour and survival of anadromous salmonids could incorporate important drivers such as oceanography, tagging/handling effects, predation, and physiology.