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Marine ecosystems on continental shelves face multiple challenges due to anthropogenic disturbances, many of which can change the seawater stoichiometry (C:N:P) and consequently elemental ratios of phytoplankton. This change in food quality may not be tolerated by all grazers and predators. Gelatinous and soft-bodied zooplankton (GZ) might be more resilient to such changes. We sampled GZ species in neritic and oceanic waters of the Northeast Pacific off British Columbia, Canada, determined their phosphorus (P) content and elemental ratios (C/P, N/P), and analysed intraspecific variability associated with size and ontogeny. P content was measured for twelve GZ taxa. P % DW (dry weight) decreased with size for the hydrozoan Aequorea sp., scyphozoans Aurelia labiata, Cyanea capillata, and the thaliacean Salpa aspera, and differed significantly for two development stages of the salp S. aspera. While C/P and N/P were mostly size and stage independent, they were highly variable. C/P values of GZ were generally higher than values of crustacean zooplankton, indicating that GZ represent poor-quality prey for non-GZ predators, and that GZ may have a higher resilience towards P-limited (low quality) prey. Changing ocean conditions and nutrient stoichiometry of prey may favour GZ, although large variability in P dynamics among GZ taxa and uncertainty about future ocean stoichiometry changes make generalisations difficult. [ABSTRACT FROM AUTHOR]

Climate change is driving biogeographic shifts in marine zooplankton. In the northeast (NE) Pacific, the distribution of the estuarine copepod, Acartia tonsa (Dana, 1849), is generally limited to California except during marine warming events where it is found as far north as British Columbia (BC). Documentation of such events relies on accurate species identification. Phylogenetic reconstruction of the genus Acartia using 768 mitochondrial cytochrome oxidase subunit I Deoxyribonucleic Acid (DNA) sequences collected worldwide demonstrates that NE Pacific A. tonsa is distinct from all conspecifics and congeners. Males of NE Pacific A. tonsa are larger with slight differences in the fifth pair of legs as compared to geographically isolated conspecifics. Accordingly, we propose NE Pacific A. tonsa be reclassified to Acartia arbruta. Analysis of mitochondrial 16S ribosomal RNA DNA sequences from 154 specimens of A. arbruta collected from California, Oregon and BC suggests that A. arbruta detected in BC is a mixture of southern populations. Southern populations are likely driven north during "warm" phases of the oceanographic processes indexed by the Pacific Decadal Oscillation, which is positively correlated with A. arbruta biomass anomalies on the continental shelf of Vancouver Island, BC. The presence of A. arbruta in BC waters is a useful bioindicator of marine warming events. [ABSTRACT FROM AUTHOR]

The effects of climate warming on ecosystem dynamics are widespread throughout the world's oceans. In the Northeast Pacific, large‐scale climate patterns such as the El Niño/Southern Oscillation and Pacific Decadal Oscillation, and recently unprecedented warm ocean conditions from 2014 to 2016, referred to as a marine heatwave (MHW), resulted in large‐scale ecosystem changes. Larval fishes quickly respond to environmental variability and are sensitive indicators of ecosystem change. Categorizing ichthyoplankton dynamics across marine ecosystem in the Northeast Pacific can help elucidate the magnitude of assemblage shifts, and whether responses are synchronous or alternatively governed by local responses to regional oceanographic conditions. We analyzed time‐series data of ichthyoplankton abundances from four ecoregions in the Northeast Pacific ranging from subarctic to subtropical: the Gulf of Alaska (1981–2017), British Columbia (2001–2017), Oregon (1998–2017), and the southern California Current (1981–2017). We assessed the impact of the recent (2014–2016) MHW and how ichthyoplankton assemblages responded to past major climate perturbations since 1981 in these ecosystems. Our results indicate that the MHW caused widespread changes in the ichthyoplankton fauna along the coast of the Northeast Pacific Ocean, but impacts differed between marine ecosystems. For example, abundances for most dominant taxa were at all‐time lows since the beginning of sampling in the Gulf of Alaska and British Columbia, while in Oregon and the southern California Current species richness increased as did abundances of species associated with warmer waters. Lastly, species associated with cold waters also increased in abundances close to shore in southern California during the MHW, a pattern that was distinctly different from previous El Niño events. We also found several large‐scale, synchronized ichthyoplankton assemblage composition shifts during past major climate events. Current climate projections suggest that MHWs will become more intense and thus our findings can help project future changes in larval dynamics, allowing for improved ecosystem management decisions. [ABSTRACT FROM AUTHOR]

Effective management of marine systems requires quantitative tools that can assess the state of the marine social-ecological system and are responsive to management actions and pressures. We applied the Ocean Health Index (OHI) framework to retrospectively assess ocean health in British Columbia annually from 2001 to 2016 for eight goals that represent the values of British Columbia's coastal communities. We found overall ocean health improved over the study period, from 75 (out of 100) in 2001 to 83 in 2016, with scores for inhabited regions ranging from 68 (North Coast, 2002) to 87 (West Vancouver Island, 2011). Highest-scoring goals were Tourism & Recreation (average 94 over the period) and Habitat Services (100); lowest-scoring goals were Sense of Place (61) and Food Provision (64). Significant increases in scores over the time period occurred for Food Provision (+1.7 per year), Sense of Place (+1.4 per year), and Coastal Livelihoods (+0.6 per year), while Habitat Services (-0.01 per year) and Biodiversity (-0.09 per year) showed modest but statistically significant declines. From the results of our time-series analysis, we used the OHI framework to evaluate impacts of a range of management actions. Despite challenges in data availability, we found evidence for the ability of management to reduce pressures on several goals, suggesting the potential of OHI as a tool for assessing the effectiveness of marine resource management to improve ocean health. Our OHI assessment provides an important comprehensive evaluation of ocean health in British Columbia, and our open and transparent process highlights opportunities for improving accessibility of social and ecological data to inform future assessment and management of ocean health. [ABSTRACT FROM AUTHOR]

People living with HIV (PLHIV) often experience pain for which opioid medications may be prescribed. Thus, these individuals are particularly vulnerable to opioid-related harms, including overdose, misuse, and addiction, particularly when prescribed at high doses. We used a comprehensive linked population-level database of PLHIV in British Columbia (BC) to identify demographic and clinical characteristics associated with being prescribed any high-dose opioid analgesic, defined as > 90 daily morphine milligram equivalents (MME/day). Among PLHIV who were prescribed opioids between 1996 and 2015 (n = 10,780), 28.2% received prescriptions of > 90 MME/day at least once during the study period. Factors positively associated with being prescribed high-dose opioid analgesics included: co-prescription of benzodiazepines (adjusted odds ratio [AOR] = 1.14; 95% confidence interval 1.11–1.17); presence of an AIDS-defining illness (ADI; AOR = 1.78; 95% CI 1.57–2.02); seen by an HIV specialist (AOR = 1.24; 95% CI 1.20–1.29); substance use disorder (AOR = 1.46; 95% CI 1.25–1.71); and more recent calendar year (AOR = 1.05; 95% CI 1.04–1.06). Given the known risks associated with high-dose opioid prescribing, future research efforts should focus on the clinical indication and outcomes associated with these prescribing practices. [ABSTRACT FROM AUTHOR]

The development of the green sea urchin (Strongylocentrotus droebachiensis) fishery in British Columbia, Canada, is presented as an example of how a precautionary approach was applied to avert collapse of a developing invertebrate fishery and to rebuild towards a sustainable fishery. We consider four components: (1) identification of the appropriate spatial scales; (2) development of scientifically-supported management strategies; (3) consideration of uncertainties; and (4) collaborations amongst scientists, fishery managers, and stakeholders. The green sea urchin fishery in British Columbia has experienced three periods: a “developing” period during which effort and landings increased, but catch per unit of effort (CPUE) declined; a “crisis” period during which effort and landings peaked and CPUE reached a minimum; and a “rebuilding to sustainable” period during which landings and effort stabilised and CPUE increased. Passive management actions (minimum size limit, seasonal closures) were introduced at the beginning of the fishery, but were unable to limit exploitation. Subsequent to the crisis period, active management measures (large area closures, quotas, and an individual quota system) were implemented based on scientific studies and appear to have stabilised the fishery. The availability of fishing logbook information from the inception of the fishery and the development of positive relationships amongst all participants in the fishery were central elements of this rebuilding process. The long time series of logbook information provided sufficient data contrasts to use two surplus production modelling techniques to develop biological reference points for management regulations. The green sea urchin fishery is now a small but important, and apparently stable, component of the dive fisheries in British Columbia. [Copyright &y& Elsevier]

Short time scale (less than seasonal) variability in commercial catch rates of smooth pink shrimp, Pandalus jordani, off the west coast of Vancouver Island, Canada, was examined in relation to changes in environmental conditions. Catch per unit of effort (CPUE) data were used as a proxy for catchability to identify environmental conditions affecting the availability of shrimp to the two main gear types in this fishery: otter trawls and beam trawls. Correlogram analyses of the 1996 CPUE (log-transformed) data from each gear type, and autocorrelation analyses of wind stress, tidal current speed, sea surface temperature and salinity, and hours of bright sunshine (the latter three as residuals from their seasonal trends) for 1996 indicated a mean decorrelation time scale of 7.7 days. This was used to construct smoothed time series of these CPUE and environmental data for 1996. Multiple regression analyses with CPUE as the dependent variable and the environmental data as independent variables were significant, explaining 44% of the variability in otter-trawl data and 35% of the beam-trawl variability. Three hypotheses are proposed to explain these results, involving interactions between the shrimp’s behaviour and environmental conditions. A significant proportion of the within-season variability in CPUE (and therefore in the availability of shrimp to fishing gear) for P. jordani off Vancouver Island can result from variations in environmental conditions which, if included in stock analyses, should reduce the variability of population abundance estimates. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cluster analysis of 20 years of zooplankton data identified 4 persistent bioregions. • Bioregions differed in zooplankton concentration, diversity, and composition. • Concordance and indicator value analysis defined species association groups. • Oceanography and zooplankton ecology are summarized along the cross-shelf gradient. Understanding oceanic ecological processes requires identifying biogeographic regions but incorporating the partitioning of planktonic communities, particularly zooplankton, has been limited and difficult. We conducted a data-driven biogeographic regionalization of zooplankton abundance using net data collected during April to October from 1995 to 2014 in the British Columbia, Canada, coastal ocean and adjacent offshore waters. After curating the data and removing rare taxa, a total of 3,721 samples and 160 species were analyzed. K-means cluster analysis of log-chord transformed zooplankton abundances was used to identify four distinct bioregions: Offshore, Deep Shelf, Nearshore, and Deep Fjord. We combined concordance and indicator value analyses to categorize the zooplankton into species association groups. Five main groups representing subarctic, subtropical, widespread shelf, neritic, and fjord specific zooplankton were indicative of specific bioregions but had distributions extending beyond their core bioregion. The spatial coherence of the bioregions and the relative contributions of the association groups to the composition of the bioregions were persistent throughout the 20-year period. The bioregions significantly differed in zooplankton abundance, biomass, and diversity and the community composition varied along the cross-shelf gradient. Variance partitioning demonstrated that the bioregionalization can be mostly explained by the differences in bottom depth, water properties, and phytoplankton concentrations. The cross-shelf differentiation of zooplankton communities was similar to other regionalization studies conducted globally, suggesting the potential for a unified framework of structuring processes and emergent community properties in the epipelagic coastal ocean. [ABSTRACT FROM AUTHOR]

• We examined pressure-response indicator relationships using a multi-model approach. • Nonlinear and linear pressure-response relationships were rare (6–12%). • Ecological responses were more commonly associated with environmental than human pressures. • Multivariate analyses helped validate the results from single pressure-response models. • Dimension reducing analyses on multiple indicators may result in information loss. One necessity of ecosystem based management is an understanding of the shape and functional forms of ecosystem responses to environmental and human pressures. Both nonlinear and linear relationships may provide leading indicators of ecosystem change and inform reference points for ecosystem approaches to management. The objectives of this study were to 1) determine functional forms of pressure-response relationships, 2) identify non-linear relationships, and 3) quantify potentially relevant management thresholds for the west coast of Vancouver Island marine ecosystem in British Columbia, Canada. To do this, a multi-model approach was applied to mechanistically linked indicators of pressures and responses. Both single pressure-response and multivariate relationships were examined. Results indicate that 1) nonlinear and linear relationships were not prevalent with the percentage of occurrence (6–12%) similar to other regions, 2) ecological responses (both linear and nonlinear) were more commonly associated with environmental pressures than human pressures, 3) gradient forest analysis generally produced similar results as single pressure-response models and identified additional nonlinearities, 4) dynamic factor analyses (DFA) reduced the numerous pressure and response indicator to a few trends, however, the process may have resulted in a loss of information, and 5) possibly due to this loss of information, gradient forest and single pressure-response analyses on DFA trends produced different results. Quantifying how pressures affect ecosystem components can provide advanced knowledge about changes in ecosystem productivity, structure, and function which can inform science advice and management strategies. Mechanistically linked pressure-response relationships should be explored further with multi-model ensembles to better inform ecosystem-based and climate-ready approaches to marine management. [ABSTRACT FROM AUTHOR]