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- OPEN ACCESSWith the influence of climate change on marine systems expanding, climate adaptation will be fundamental for the future of fisheries management. An exponential increase in Atlantic halibut Hippoglossus hippoglossus landings over the past decade has coincided with warming ocean temperatures. Here, we explore how historical changes in abundance have been linked to changing thermal habitat conditions and project trends with a warming climate under different emissions scenarios. From 1990 to 2018, available thermal habitat increased by 11.6 ± 7.35% and growing degree days have increased by 13.5 ± 7.86 °C·days across the region. With warming, the probability of occurrence is projected to increase up to 20.5% in Canada by 2085 under RCP 8.5 for Atlantic halibut. Our results suggest that shifting patterns of halibut distribution and abundance are linked to thermal conditions and that continued warming will likely continue to enhance habitat conditions, leading to increased abundance in the Canadian range. Collectively, these results illustrate the influence of shifting environmental conditions on population dynamics and emphasize the importance of adaptive management practices in a dynamic future climate.
- OPEN ACCESSTrash capture devices (TCDs) are a rapidly evolving tool for municipal governments, non-governmental organizations, and industries to divert litter from our waterways. Here, we introduce protocols to initiate trash trapping projects to quantify and characterize captured anthropogenic litter based on a case study using Seabins. In addition, we have introduced a network for global data collection via TCDs. Our first protocol is a visual audit of the potential site to inform the type and location for TCD deployment. Our next two protocols quantify and characterize the litter captured by TCDs: (1) a simple protocol intended for daily monitoring and (2) a detailed protocol to characterize and quantify all large debris (>3 cm) and a subset of the small debris (2 mm–3 cm) caught in the devices. Using Seabins in the Toronto Harbour to test our methodology, we found that our subsampling methodology has a 6.9% error rate. Over a 19-week period, the Seabins captured ∼85 000 pieces of small debris. Our study highlights the utility of TCDs and proposes methods to realize this utility globally. TCDs should become more widespread and utilized as a triple threat: a cleanup tool, a data collection tool, and a platform for outreach and education.
- OPEN ACCESS
- Juliano Palacios-Abrantes,
- Sarah M. Roberts,
- Talya ten Brink,
- Tim Cashion,
- William W.L. Cheung,
- Anne Mook, and
- Tu Nguyen
The world has set ambitious goals to protect marine biodiversity and improve ocean health in the face of anthropogenic threats. Yet, the efficiency of spatial tools such as marine reserves to protect biodiversity is threatened as climate change shifts species distributions globally. Here, we investigate the ability of global marine reserves to protect fish biomass under future climate change scenarios. Moreover, we explore regional patterns and compare worlds with and without marine reserves. We rely on computer modeling to simulate an utopian world where all marine reserves thrive and ocean governance is effective. Results suggest that climate change will affect fish biomass in most marine reserves and their surrounding waters throughout the 21st century. The biomass change varies among regions, with tropical reserves losing biomass, temperate ones gaining, and polar reserves having mixed effects. Overall, a world with marine reserves will still be better off in terms of fish biomass than a world without marine reserves. Our study highlights the need to promote climate resilient conservation methods if we are to maintain and recover biodiversity in the ocean under a changing world. - OPEN ACCESSSeasonal variation in seagrass growth and senescence affects the provision of ecosystem services and restoration efforts, requiring seasonal monitoring. Remotely piloted aircraft systems (RPAS) enable frequent high-resolution surveys at full-meadow scales. However, the reproducibility of RPAS surveys is challenged by varying environmental conditions, which are common in temperate estuarine systems. We surveyed three eelgrass (Zostera marina) meadows in Newfoundland, Canada, using an RPAS equipped with a three-color band (red, green, blue [RGB]) camera, to evaluate the seasonal reproducibility of RPAS surveys and assess the effects of flight altitude (30–115 m) on classification accuracy. Habitat percent cover was estimated using supervised image classification and compared to corresponding estimates from snorkel quadrat surveys. Our results revealed inconsistent misclassification due to environmental variability and low spectral separability between habitats. This rendered differentiating between model misclassification versus actual changes in seagrass cover infeasible. Conflicting estimates in seagrass and macroalgae percent cover compared to snorkel estimates could not be corrected by decreasing the RPAS altitude. Instead, higher altitude surveys may be worth the trade-off of lower image resolution to avoid environmental conditions shifting mid-survey. We conclude that RPAS surveys using RGB imagery alone may be insufficient to discriminate seasonal changes in estuarine subtidal vegetated habitats.
- OPEN ACCESSMarine Protected Areas (MPAs) are conservation tools that promote biodiversity by regulating human impacts. However, because MPAs are fixed in space and, by design, difficult to change, climate change may challenge their long-term effectiveness. It is therefore imperative to consider anticipated ecological changes in their design. We predict the time of emergence (ToE: year when temperatures will exceed a species’ tolerance) of 30 fish and invertebrate species in the Scotian Shelf-Bay of Fundy draft network of conservation areas based on climate projections under two contrasting emission scenarios (RCP 2.6 and RCP 8.5). We demonstrate a strong Southwest-to-Northeast gradient of change under both scenarios. Cold water-associated species had earlier ToEs, particularly in southwesterly areas. Under low emissions, 20.0% of habitat and 12.6% of species emerged from the network as a whole by 2100. Under high emissions, 51% of habitat and 42% of species emerged. These impacts are expected within the next 30–50 years in some southwestern areas. The magnitude and velocity of change will be tempered by reduced emissions. Our identification of high- and low-risk areas for species of direct and indirect conservation interest can support decisions regarding site and network design (and designation scheduling), promoting climate resilience.
- OPEN ACCESS
- Tyler D. Eddy,
- Daniel Duplisea,
- Matthew D. Robertson,
- Raquel Ruiz-Díaz,
- C. Abraham Solberg, and
- Fan Zhang
Fish populations are dynamic; their productivity depends on the environment, predator and prey interactions, and fisheries harvest rates. Failure to account for these factors in fisheries science and management can lead to a misestimation of stock dynamics and productivity, resulting in overexploitation or forgone fisheries yield. Using an online survey, we asked fisheries scientists, industry stakeholders, Indigenous partners, and non-governmental organizations whether changing ecosystem productivity was a problem in their experience, how often dynamic approaches to fisheries reference points have been adopted, what methods had been used, and what fisheries they had been applied to. Changing fisheries or ecosystem productivity was reported as an issue by 96% of respondents; however, 74% of respondents said they had never seen dynamic reference points implemented, 16% said in very few instances, while 10% said frequently. The most common barriers to implementation of dynamic approaches in fisheries management were institutional inertia and uncertainty about whether a change in productivity was lasting. We discuss trade-offs between fisheries management performance and stability. - OPEN ACCESSThe impact of the southern Gulf of St. Lawrence American lobster (Homarus americanus) fishery on species bycatch is currently unknown. The composition of the incidental catch, both nonharvestable lobster (by fisheries regulations) and nonlobster species, was systematically collected over the 2015 spring and summer fishing seasons. A total of 51 948 (7147 were nonlobster taxa) individual organisms weighing 13 987.60 kg (1223.91 kg of nonlobster taxa) were captured as bycatch during 73 fishing trips. By weight per trip, the most common lobster bycatch were undersized male and females, and the highest nonlobster species catch were Atlantic rock crab (Cancer irroratus). A semiquantitative assessment of injury and vitality was applied to bycatch as a proxy for discard mortality. The majority of the individuals assessed for visible injury were deemed uninjured (98% both fish and invertebrates); however, postrelease mortality was not measured. A smaller study in 2019 corroborated the 2015 catches and supported current assumptions that the passive gear type, the low diversity of bycatch, and the rapid hand-sorting of the trap minimize the impact of the lobster fishery on incidentally captured taxa. Further scientific monitoring is recommended to better account for all sources of mortality in stock assessments and rebuilding plans.
- OPEN ACCESSIn 2020, the COVID-19 pandemic interrupted all aspects of human activity, including environmental research and monitoring. Despite a lack of laboratory access and other restrictive measures, we adapted an existing community science monitoring program to continue through the summer of 2020. We worked with local community groups to recruit 58 volunteers who collected lake water samples from 60 sites on 16 lakes in south-central Ontario from June to September 2020. We organized drop-off depots and had volunteers freeze samples to monitor nearshore nutrients (phosphorus and nitrogen) and chlorophyll-a. A survey was distributed to volunteers to analyze lake-front property owners’ activities during the pandemic. We found spatial patterns in nearshore water quality across the lakes, with sub-watershed development being a significant predictor of nutrients and chlorophyll-a. Additionally, pre-pandemic (2019) and pandemic (2020 and 2021) nutrient concentrations were compared, but there was no clear impact of the pandemic on nearshore nutrient concentrations, despite changes in lake-front property owners activities. Overall, this study demonstrated the ability of community science to provide water quality data on a large spatial scale despite a major societal disruption, providing insight into regional nutrient trends during the first year of the pandemic.
- OPEN ACCESS
- Andrea Bryndum-Buchholz,
- Julia L. Blanchard,
- Marta Coll,
- Hubert Du Pontavice,
- Jason D. Everett,
- Jerome Guiet,
- Ryan F. Heneghan,
- Olivier Maury,
- Camilla Novaglio,
- Juliano Palacios-Abrantes,
- Colleen M. Petrik,
- Derek P. Tittensor, and
- Heike K. Lotze
Climate change is altering marine ecosystems across the globe and is projected to do so for centuries to come. Marine conservation agencies can use short- and long-term projections of species-specific or ecosystem-level climate responses to inform marine conservation planning. Yet, integration of climate change adaptation, mitigation, and resilience into marine conservation planning is limited. We analysed future trajectories of climate change impacts on total consumer biomass and six key physical and biogeochemical drivers across the Northwest Atlantic Ocean to evaluate the consequences for Marine Protected Areas (MPAs) and Other Effective area-based Conservation Measures (OECMs) in Atlantic Canada. We identified climate change hotspots and refugia, where the environmental drivers are projected to change most or remain close to their current state, respectively, by mid- and end-century. We used standardized outputs from the Fisheries and Marine Ecosystem Model Intercomparison Project and the 6th Coupled Model Intercomparison Project. Our analysis revealed that, currently, no existing marine conservation areas in Atlantic Canada overlap with identified climate refugia. Most (75%) established MPAs and more than one-third (39%) of the established OECMs lie within cumulative climate hotspots. Our results provide important long-term context for adaptation and future-proofing spatial marine conservation planning in Canada and the Northwest Atlantic region. - OPEN ACCESSAnthropogenic pressures, including urban and agricultural expansion, can negatively influence a lake's capacity to provide aquatic ecosystem services (ES). However, identifying lakes most at risk of losing their ES (i.e., higher vulnerability) requires integrating information on lake ecological state, global change threats, and ES use. Here, we provide a social–ecological framework that combines these features within a regional context by evaluating the ecological state of 659 lakes across Canada. Using the deviation of impacted lakes from reference ones, we identified much higher total nitrogen and chloride concentrations as the main indicators of an altered lake ecological state in all regions identified. Lake ecological state was mapped using an additive colour model along with regional scores of threat levels and recreational ES use. Urban and agriculturally developed areas were linked to higher lake vulnerability and ES loss. Lakes in Southern Ontario were most concerning, being highly altered, under threat, and heavily used. Lakes near coastal urban centers were altered and used, but less threatened, whereas those in the Prairies were altered and threatened, but less used. Our novel framework provides the first social–ecological geography of Canadian lakes, and is a promising tool to assess lake state and vulnerability at scales relevant for management.
- OPEN ACCESSThe degree to which human actions affect marine fisheries has been a fundamental question shaping people’s relationship with the sea. Today, divergences in stakeholder views about the impacts of human activities such as fishing, climate change, pollution, and resource management can hinder effective co-management and adaptation. Here, we used surveys to construct mental models of the Maine lobster fishery, identifying divergent views held by two key stakeholder groups: lobster fishers and marine scientists. The two groups were differentiated by their perceptions of the relative impact of pollution, water temperature, and fishing. Notably, many fishers perceive the process of fishing to have a positive effect on fisheries through the input of bait. Scientists exhibited a statistically significantly stronger concern for climate change and identified CO2 as one of the dominant pollutants in the Gulf of Maine. However, fishers and scientists agreed that management has a positive impact, which appeared to be a change over the past two decades, possibly due to increased collaboration between the two groups. This work contributes to the goal of decreasing the distance between stakeholder perspectives in the context of a co-managed fishery as well as understanding broader perceptions of impacts of human activities on marine ecosystems.
- OPEN ACCESSIn response to colonial research paradigms that have subjugated Indigenous Peoples, knowledges, lands, and waters, Indigenous research methodologies have emerged to center Indigenous visions and voices in research practice. Here, we employ such methodologies to improve collective understanding of the state and future of wild Pacific salmon (Oncorhynchus spp.) and fish–people–place relationships across British Columbia’s three largest salmon-producing rivers: the Fraser, Skeena, and Nass. Through partnerships with 18 communities of “Salmon People” and semi-structured interviews with 48 knowledge holders (i.e., Elders), we learned that, on average, Elders spent more than half of a century actively engaged in salmon fishing and processing. Modern salmon catches are reported to be approximately one-sixth of what they were estimated to be five to seven decades ago, and the top five threats to salmon identified by Elders included (i) aquaculture, (ii) climate change, (iii) contaminants, (iv) industrial development, and (v) infectious diseases. Threat priorities varied regionally, reflecting distinct lived experiences and regional variation in the prevalence and impact of different threats. Elders perceived threats to salmon equally as threats to aquatic health and human well-being, with evidence that the relationships between people and water, and salmon and people, are being profoundly transformed.
- OPEN ACCESSEthnobiological studies on folk, common, or popular names that fishers use to identify fish can help improve fisheries monitoring and collaborations between fishers and researchers. This study investigates fishers’ knowledge (recognition, naming, and habitat use) on 115 and 119 fish species, respectively, in the Negro and Tapajos Rivers, two megadiverse rivers in the Brazilian Amazon, and investigates the relationship between such knowledge and fish importance to fisheries, fish abundance, and fish size. We also compared fishers’ perceptions on fisheries and fish abundance with literature data on fish harvests and fish sampling. We interviewed 16 fishers in 16 communities (one fisher per community, 8 communities along each river). These fishers recognized an average of 91 ± 10.4 species in the Negro River and 115 ± 7.2 species in the Tapajos River, but all fishers recognized 114 species in Negro and all species in Tapajos. The fishers’ knowledge of fish species was positively related to fishers’ perceptions on fish abundance, size, and importance to fisheries in the Negro, but only positively related to fish size in the Tapajos. Our results highlight the usefulness of fishers’ knowledge to providing data on use and cultural relevance of fish species in high diversity aquatic ecosystems.
- OPEN ACCESS
- Sachiko Ouchi,
- Lori Wilson,
- Colette C.C. Wabnitz,
- Christopher D. Golden,
- Anne H. Beaudreau,
- Tiff-Annie Kenny,
- Gerald G. Singh,
- William W.L. Cheung,
- Hing Man Chan, and
- Anne K. Salomon
Understanding mechanisms that promote social-ecological resilience can inform future adaptation strategies. Among seafood dependent communities, these can be illuminated by assessing change among fisheries portfolios. Here, in collaboration with a Coast Salish Nation in British Columbia, Canada, we used expert Indigenous knowledge and network analyses to chronicle differences in fisheries portfolios pre and post a social-ecological regime shift. We then evaluated key drivers of change using semi-structured interviews. We found that while portfolios decreased in diversity of seafood types harvested and consumed among individuals overtime, portfolios increased in their diversification at the community level because more similar seafoods within less diverse individual portfolios were more commonly harvested and consumed by the Nation as a whole. Thus, diversity can operate simultaneously in opposing directions at different scales of organization. Experts identified four key mechanisms driving these changes, including commercial activities controlled by a centralized governance regime, intergenerational knowledge loss, adaptive learning to new ecological and economic opportunities, and the trading of seafood with other Indigenous communities. Unexpectedly, increased predation by marine mammals was also flagged as a key driver of change. Adaptation strategies that support access to and governance of diverse fisheries, exchange of seafoods among communities, and knowledge transfer among generations would promote social-ecological resilience, food security, and community well-being. - OPEN ACCESS
Thermal sensitivity and flow-mediated migratory delays drive climate risk for coastal sockeye salmon
- William I. Atlas,
- Karl M. Seitz,
- Jeremy W.N. Jorgenson,
- Ben Millard-Martin,
- William G. Housty,
- Daniel Ramos-Espinoza,
- Nicholas J. Burnett,
- Mike Reid, and
- Jonathan W. Moore
Climate change is subjecting aquatic species to increasing temperatures and shifting hydrologic conditions. Understanding how these changes affect individual survival can help guide conservation and management actions. Anadromous Pacific salmon (Oncorhynchus spp.) in some large river systems are acutely impacted by the river temperatures and flows encountered during their spawning migrations. However, comparatively little is known about drivers of en route mortality for salmon in smaller coastal watersheds, and climate impacts may differ across watersheds and locally adapted salmon populations. To understand the effects of climate on the survival of coastal sockeye salmon (Oncorhynchus nerka; hísn in Haíɫzaqv), we tagged 1785 individual fish with passive integrated transponders across four migration seasons in the Koeye River—a low-elevation watershed in coastal British Columbia—and tracked them during their relatively short migration (∼13 km) from river entry to spawning grounds. Overall, 64.7% of sockeye survived to enter the spawning grounds, and survival decreased rapidly when water temperatures exceeded 15 °C. The best-fitting model included an interaction between river flow and temperature, such that temperature effects were worse when flows were low, and river entry ceased at the lowest flows. Results revealed temperature-mediated mortality and migration delays from low water that may synergistically reduce survival among sockeye salmon returning to coastal watersheds. - OPEN ACCESSPacific sand lance (Ammodytes personatus) and surf smelt (Hypomesus pretiosus) are ecologically important forage fish in the marine food webs within the Salish Sea, including British Columbia (BC). Although important, little information exists around the spatiotemporal distribution of these fishes’ beach spawning habitat in the BC Salish Sea. In 2017, the Mount Arrowsmith Biosphere Region Research Institute initiated spawning beach surveys within the Mount Arrowsmith Biosphere Region (MABR). Surveys have geographically expanded along the eastern Vancouver Island coastline between Bowser and Cowichan Bay, BC, including Gabriola Island and Thetis Island. Pacific sand lance embryos have been detected at 17 beaches, with six beaches located within the MABR. Pacific sand lance spawning events have been detected between November and mid-February, with the bulk of embryos detected in November and December. To date, surf smelt embryos have not been detected at the 56 different beaches. These data begin to fill existing data gaps surrounding Pacific sand lance and surf smelt in BC. Furthermore, longer-term data submissions to the Strait of Georgia Data Centre, an open-access database, will provide the necessary data needed to advocate for improved regulatory protections for these ecologically important fish and their spawning habitat.
- OPEN ACCESS
- Bryant C. DeRoy,
- Vernon Brown,
- Christina N. Service,
- Martin Leclerc,
- Christopher Bone,
- Iain McKechnie, and
- Chris T. Darimont
Environmental management and monitoring must reconcile social and cultural objectives with biodiversity stewardship to overcome political barriers to conservation. Suitability modelling offers a powerful tool for such “biocultural” approaches, but examples remain rare. Led by the Stewardship Authority of the Kitasoo/Xai’xais First Nation in coastal British Columbia, Canada, we developed a locally informed suitability model for a key biocultural indicator, culturally modified trees (CMTs). CMTs are trees bearing evidence of past cultural use that are valued as tangible markers of Indigenous heritage and protected under provincial law. Using a spatial multi-criteria evaluation framework to predict CMT suitability, we developed two cultural predictor variables informed by Kitasoo/Xai’xais cultural expertise and ethnographic data in addition to six biophysical variables derived from LiDAR and photo interpretation data. Both cultural predictor variables were highly influential in our model, revealing that proximity to known habitation sites and accessibility to harvesters (by canoe and foot) more strongly influenced suitability for CMTs compared with site-level conditions. Applying our model to commercial forestry governance, we found that high CMT suitability areas are 51% greater inside the timber harvesting land base than outside. This work highlights how locally led suitability modelling can improve the social and evidentiary dimensions of environmental management. - OPEN ACCESSMicroplastics are globally ubiquitous contaminants, but quantitative data on their presence in freshwater environments are sparse. This study investigates the occurrence, composition, and spatial trends of microplastic contamination in the North Saskatchewan River flowing through Edmonton, Alberta, the fifth largest city in Canada. Surface water samples were collected from seven sites throughout the city, upstream and downstream of the city, and near potential point sources (i.e., a wastewater treatment plant). Samples were spiked with fluorescent microbeads as internal standards and extracted by wet peroxide oxidation and density floatation. Microplastics were found in all samples, ranging in concentration from 4.6 to 88.3 particles·m−3 (mean = 26.2 ± 18.4 particles·m−3). Fibers were the dominant morphology recovered, and most were of anthropogenic origin and chemically identified as dyed cotton or polyester by Raman microspectroscopy. The majority of fragments were identified as polyethylene or polypropylene. No upstream to downstream differences were found in concentration, size distribution, or morphological composition suggesting nonpoint sources of microplastics to the river. This study represents one of the first investigations into the occurrence of microplastics in the freshwater environment in western Canada and will provide a baseline for future studies.
- OPEN ACCESS
- Jade R. Steel,
- William I. Atlas,
- Natalie C. Ban,
- Kyle Wilson,
- Jayda Wilson,
- William G. Housty, and
- Jonathan W. Moore
Wild salmon are central to food security, cultural identity, and livelihoods of coastal Indigenous communities. Yet ongoing inequities in governance, declining fish populations, and mixed-stock ocean fisheries may pose challenges for equitable access between Indigenous fishers and other non-Indigenous fishers. We sought to understand current perceptions among Haíłzaqv (Heiltsuk) fishers towards salmon fisheries and their management. We conducted dockside surveys with both Haíłzaqv fishers and sport fishers, and in-depth interviews with Haíłzaqv fishers, community members, and natural resource managers. From these surveys and interviews we quantified satisfaction among both food, social, and ceremonial fishers and visiting recreational fishers with the current salmon fishery and associated social-ecological drivers, and characterized perceptions among Haíłzaqv people of salmon fisheries and management. Second, we synthesized community perceptions of the revitalization of terminal, communally run salmon fisheries within Haíłzaqv territory as a tool for their future salmon management. Finally, we elicited information from Haíłzaqv fishers about the barriers people in their community currently face in accessing salmon fisheries. Our findings suggest that low salmon abundance, increased fishing competition, and high costs associated with participation in marine mixed-stock fisheries currently hinder access and equity for Haíłzaqv fishers. This community-based research can help strengthen local, Indigenous-led management of salmon into the future. - OPEN ACCESS
- Joanne L. Parrott,
- Grazina Pacepavicius,
- Kallie Shires,
- Stacey Clarence,
- Hufsa Khan,
- Madelaine Gardiner,
- Cheryl Sullivan, and
- Mehran Alaee
Metformin is a glucose-lowering drug taken for diabetes. It is excreted by humans in urine and detected in municipal wastewater effluents and rivers. Fathead minnows (Pimephales promelas) were exposed over a life cycle to measured concentrations of metformin: 3.0, 31, and 322 μg/L. No significant changes were observed in survival, maturation, growth, condition factor, or liver size. Relative ovary size of females exposed to 322 μg/L metformin was significantly larger than controls. There was no induction of vitellogenin in plasma of minnows, and gonad maturation was not statistically different from controls. The start of breeding was delayed by 9–10 d in the mid- and high metformin treatments (statistically significant only in the mid-concentration), but numbers and quality of eggs were not statistically different from controls. There were no effects of metformin on survival or growth of offspring. Exposure to metformin at environmentally relevant concentrations (i.e., 3.0 and 31 μg/L metformin) caused no adverse effects in fathead minnows exposed for a life cycle, with the exception of a delay in time to first breeding (that did not impact overall egg production). The results of the study are important to help understand whether metformin concentrations in rivers and lakes can harm fishes.