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The Pacific Region Groundfish Integrated Fisheries Management Plan lists approximately 80 species-area fish stocks for which annual total allowable catches are required, most of which are applied as individual transferable quotas within the British Columbia (BC) integrated groundfish fishery. The majority of fish stocks encountered by the integrated groundfish fishery are considered data-limited, where data-limited stocks are defined as those with insufficient data to reliably estimate stock status or estimate abundance or productivity with conventional stock assessment methods such as statistical catch-at-age models. In recent decades, Fisheries and Oceans Canada (DFO) groundfish stock assessments have focused on data-rich stocks, resulting in a subset of stocks with full stock assessments, while many stocks with less informative data remain unassessed. The DFO Sustainable Fisheries Framework, legislated via the Fish Stocks provisions in the Fisheries Act, requires that fish stocks be managed at sustainable levels--specifically at biomass levels above the Limit Reference Point (LRP). For data-limited stocks, data are often insufficient to adequately account for uncertainty in the assessment of stock status relative to biological reference points in traditional stock assessments. Instead of focusing on the explicit knowledge of current stock status, we propose a management-oriented approach that emphasizes selecting management procedures (MPs) that have a high likelihood of maintaining fish stocks above implicitly known reference points across multiple plausible states of nature, regardless of the quality and quantity of available data. Worldwide there has been a movement towards MP (or management strategy evaluation) approaches to providing science advice on fish stocks via closed-loop simulation. Closed-loop simulation differs from conventional stock assessment because it simulates feedback between the implementation of MPs and a simulated system representing the fish stock and its environment, described by one or more operating models (OMs). This document presents a methodology for developing appropriate OMs, testing suites of MPs, and identifying MPs that best meet the objectives of fisheries management and stakeholders. We outline six best-practice steps for MP approaches: (1) defining the decision context, (2) setting objectives and performance metrics, (3) specifying OMs, (4) selecting candidate MPs, (5) conducting closed-loop simulations, and (6) presenting results to evaluate trade-offs. We then describe our proposed approach (the "MP Framework") and how it aims to accomplish each of these best-practice steps. Included in our framework are provisional conservation and fishery objectives and performance metrics based on Sustainable Fisheries Framework policies, a provisional library of data-limited MPs that are appropriate for BC groundfish stocks, and provisional visualizations to help decision-makers evaluate performance of MPs and trade-offs amongst MPs. We undertake a case study of the Rex Sole (Glyptocephalus zachirus) stock in the West Coast Vancouver Island groundfish management area (Area 3CD) to demonstrate an application of the MP Framework. The case study develops six reference-set OMs and two robustness-set OMs. The case study reveals a set of survey-index-based MPs, constant catch, and surplusproduction-based MPs that achieve > 0.9 probability (9 times out of 10 chance) of maintaining biomass above the LRP in the long term (35-50-years in the future) while maintaining a > 0.8 probability (4 times out of 5 chance) of maintaining catches at or above recent (5-year) average levels in the near future (1-10 years) in the reference-set OMs. We also present performance metrics related to the long-term probability of biomass remaining above the Upper Stock Reference, the long-term probability of fishing below FMSY (fishing mortality at maximum sustainable yield), the long-term probability of maintaining catches above recent avervage levels, and the probability of catch variability remaining below historical levels. Four of the MPs achieved only slightly lower performance metrics in the robustness OMs, compared to the reference-set OMs, while other MPs were more sensitive to these OM robustness scenarios. We highlight issues regarding reference points, MP tuning, assessment frequency and triggers, the inclusion of environmental effects, assessing the value of information, and use of this framework as part of stock rebuilding plans. Throughout, our framework emphasizes transparency and reproducibility and to that end we develop an associated package for the statistical software R that facilitates applications of the framework. Overall, we intend this framework to improve the capacity for Pacific DFO Science to provide evidence-based catch advice for more groundfish stocks--regardless of data limitations--in a standardized and transparent manner consistent with the DFO Sustainable Fisheries Framework, the Fish Stocks provisions in the Fisheries Act, and international best practices. [ABSTRACT FROM AUTHOR]

Modern survey and fishery observation programs generate vast quantities of data. However, regulatory agencies often lack the capacity to translate those data into effective monitoring information. Here, we describe an approach of automated visualization of raw fisheries data and demonstrate it with a report on 113 groundfish species in Pacific Canadian waters. Our implementation consists of two pages per species that show standardized visualizations of temporal trends and spatial distributions of commercial catches and survey indices, along with analyses of age, size, maturity, and growth. The approach facilitates discussions on stock assessment and survey prioritization, increases transparency about data holdings, and makes data available for regular review by interested parties. We encourage other agencies to consider similar approaches for their own data. [ABSTRACT FROM AUTHOR]

Anthropogenic CO2is decreasing oceanic pH and contributing to seawater warming. We tested the effects of low pH and high temperature at levels predicted for 2100 on an ecologically important predator–prey system (sea stars,Asterias rubens, and mussels,Mytilus edulis) from the NW Atlantic coast. Mussels are dominant competitors for space and important ecosystem engineers, while sea stars control mussel populations and thus local community structure. We found sea stars to be negatively affected in growth rate by low pH, with growth further reduced by a high temperature. In contrast, mussel growth rate was positively affected by low pH, with no response to temperature within the tested range. Predation of sea stars on mussels, measured as per-capita consumption rate, decreased in acidified conditions by 50%. Our study suggests that mussels may not be negatively affected by pH at the levels predicted for the end of this century and that mussels may be subjected to a reduced predation from sea stars under future conditions. [ABSTRACT FROM PUBLISHER]

Ocean acidification resulting from the global increase in atmospheric CO2 concentration is emerging as a threat to marine species, including crustaceans. Fisheries involving the American lobster (Homarus americanus) are economically important in eastern Canada and United States. Based on ocean pH levels predicted for 2100, this study examined the effects of reduced seawater pH on the growth (carapace length) and development (time to molt) of American lobster larvae throughout stages I-III until reaching stage IV (postlarvae). Each stage is reached after a corresponding molt. Larvae were reared from stage I in either acidified (pH = 7.7) or control (pH = 8.1) seawater. Organisms in acidified seawater exhibited a significantly shorter carapace length than those in control seawater after every molt. Larvae in acidified seawater also took significantly more time to reach each molt than control larvae. In nature, slowed progress through larval molts could result in greater time in the water column, where larvae are vulnerable to pelagic predators, potentially leading to reduced benthic recruitment. Evidence was also found of reduced survival when reaching the last stage under acidified conditions. Thus, from the perspective of larval ecology, it is possible that future ocean acidification may harm this important marine resource. [ABSTRACT FROM AUTHOR]