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Atlantic herring (Clupea harengus) are economically and ecologically significant but have been in decline in Atlantic Canada due to an uncertain combination of environmental recruitment controls, predation, and fishing (commercial fishery and poorly documented bait removals). Fisheries and Oceans Canada partially closed Atlantic mackerel (Scomber scombrus) and herring fisheries in March 2022 amid controversy and disagreement. Here, we develop a conceptual model for natural and anthropogenic controls on herring abundance centered on the southern Gulf of St. Lawrence (sGSL) and evaluate the likely importance of each. We provide the first estimates of the magnitude of bait fishery withdrawals in the sGSL. The decline in sGSL herring is likely driven by natural predation exacerbated by fishing. Bait fishery removals were 182 tonnes in 2021, suggesting that previous estimates for removals of spring-spawning herring were ∼30% too low. Fisheries closure is consistent with a precautionary approach given uncertainties and irreversibility of stock collapse. Ecosystemic models are needed but will be difficult to develop given the incomplete understanding of prey substitutability and net effect of interacting environmental processes. [ABSTRACT FROM AUTHOR]

Fisheries and Oceans Canada (DFO) is developing a precautionary approach (PA) framework for the management of Atlantic Salmon fisheries for DFO Gulf Region rivers. DFO (2018) previously defined river-specific Limit Reference Points (LRPs) for Atlantic Salmon rivers in DFO Gulf Region. This document addresses the definition of the Upper Stock Reference (USR), the Target Reference (TR), and the maximum Removal Rate (RR) reference points in the healthy zone. The USR is defined as 80% of recruitment at maximum sustainable yield and the TR is recruitment at maximum sustainable yield. The maximum removal rate is the exploitation rate that results in maximum sustainable yield. Reconstructed time series of anadromous Atlantic Salmon returns and spawners from two rivers of DFO Gulf Region augmented by data from twelve rivers of the province of Quebec that are proximate to the rivers of the Gulf Region are analyzed. An approach using ratios is proposed to define the USR and TR values based on the defined LRP values. The ratio quantifies the spread between LRP and USR values derived from adult to adult data which is then applied to the LRP which is defined using only the freshwater phase of the salmon life cycle. The mean ratio of USR to LRP for the twelve rivers analyzed is 3.8 and the ratio of TR to LRP is 4.7. The resulting boundary of the cautious / healthy zones is approximately four times higher than the boundary of the critical and cautious zones. The maximum removal rate is taken directly from the adult to adult stock and recruitment analyses and equals 0.6. The LRP, USR, and TR are defined for each river of DFO Gulf Region known or assumed to have an anadromous salmon run. The reference points are expressed in units of eggs contributed by all anadromous sea age and size groups. [ABSTRACT FROM AUTHOR]

Fisheries and Oceans Canada (DFO) is developing a precautionary approach (PA) framework for the management of the Atlantic Salmon recreational fisheries for DFO Gulf Region rivers. A DFO Fisheries Management-led working group (DFO-WG) convened over the previous year to discuss and develop candidate harvest decision rules (HDRs) for the Atlantic Salmon recreational fishery using the Miramichi River as a case study. The candidate HDRs for the recreational fishery are evaluated for compliance to the PA policy and supporting science advice. The candidate HDRs specify management measures for different levels of abundance prior to recreational fisheries rather than being specific about exploitation rates. There is insufficient information to determine the extent to which the described management measures will change the exploitation rates and losses due to fishing. Using historical exploitation rates and assumed catch and release mortality rates from the Miramichi River, the management measures in the candidate HDRs are translated into the proportion of the total eggs lost from recreational fishing. The losses for similar management measures are higher in the Northwest Miramichi compared to the Southwest Miramichi because of differing biological characteristics and seasonal catch profiles between the two rivers. Several elements of the candidate HDRs, such as adjusting losses for three status zones and maximum losses being less than the removal rate reference, comply with the PA policy. Other elements of the candidate HDRs may not comply with the PA policy, subject to interpretation. One key element is the interpretation of the PA statements that removals be kept to the lowest level possible and no tolerance for preventable decline when the stock is in the critical zone. Both candidate rules would allow a directed catch and release recreational fishery when the abundance is in the critical zone; directed fisheries would only be closed if the abundance before fishing was < 15% or < 25% of the Limit Reference Point (LRP), dependent on the rule. The losses from a catch and release fishery in the critical zone would be approx. 1% of the eggs prior to the fishery but could be as high as 4 to 7% if the season-adjusted catch and release mortality rate was in the range of 16 to 25% as indicated from a wider meta-analysis of studies and mean water temperatures in the Miramichi, rather than 3% mortality rate that has been used to date. The implementation of the candidate HDRs requires a forecast of expected abundance prior to the fishery. The performance of the candidate HDRs and compliance to the PA policy will need to be reevaluated to take account of the uncertainties and biases of the forecast model and the decision making process. [ABSTRACT FROM AUTHOR]

Atlantic Herring (Clupea harengus) in Northwest Atlantic Fisheries Organization (NAFO) Division 4T, referred to as the southern Gulf of St. Lawrence (sGSL), consists of two spawning components, spring spawners and fall spawners. This document presents the most recent information on trends in abundance, distribution, and harvest for the spring and fall spawning Herring components in NAFO Division 4T. This includes catch-at-age and catch-per-unit-effort (CPUE) indices, fisheries-independent acoustic indices, experimental gillnet survey indices, mesh selectivity, fishery-dependent acoustic indices and catches in the multi-species bottom trawl survey of the sGSL. The data and indices are reported for the sGSL for the spring spawners, and regionally-disaggregated (North, Middle, and South regions) for the fall spawners where applicable. Spring spawners were assessed using a statistical catch at age (SCA) model that allowed for time-varying catchability to the gillnet fishery and time-varying natural mortality. The model estimated that spawning stock biomass (SSB) has been in the critical zone of the Precautionary Approach framework since 2002. The SSB median estimate in April 1 2022 is estimated to be 28,835 tons (t); 62% of the limit reference point (LRP = 46,340 t). Under current low recruitment and high natural mortality conditions, this stock is not expected to recover in the short or the long term. Reducing fishing mortality will have marginal effects on the projected SSB trends. By 2027, the probability of exceeding the LRP was not more than 20% at all catch levels, with SSB values ranging between 32,500 and 35,400 t. Fall spawners were assessed as regionally-disaggregated populations using a SCA model that allowed for time-varying catchability to the gillnet fishery and time-varying natural mortality. Estimated SSB has been declining in all three regions in recent years and is currently in the Cautious Zone of the Precautionary Approach framework. At the target catch level in 2021 (~12,000 t), the probabilities of a 5% increase in SSB by 2024 are all under 40%. Long-term projections show a continuous decline of SSB, however the probability of moving into the Critical Zone (under the LRP) by 2027 was 0% at all catch levels. As a consequence of low productivity and high natural mortality, exploitation of this stock should assert caution until high recruitment is observed for consecutive years. [ABSTRACT FROM AUTHOR]

The Estuary and Gulf of St. Lawrence northern shrimp (Pandalus borealis) stock status is determined every year by examining many indicators from the commercial fishery and the research survey. This document presents the data and methods that were used to produce the commercial fishery statistics from 1982 to 2021 and the indicators from the survey from 1990 to 2021. In addition, the document presents some ecosystem characteristics observed in the estuary and the northern Gulf of St. Lawrence. These can have an impact on the dynamics of northern shrimp stocks through, among other things, effects on spatial distribution, growth, reproduction and trophic relationships. The elements of the precautionary approach are also presented in this document. [ABSTRACT FROM AUTHOR]

Atlantic Herring in the southern Gulf of St. Lawrence (sGSL) consists of two spawning components: spring spawners and fall spawners. This document presents the most recent information on trends in abundance, distribution, and harvest for the spring and fall spawning Herring components in NAFO Division 4T. This includes catch-at-age and catch-per-unit-effort (CPUE) indices, fisheries-independent acoustic indices, experimental gillnet survey indices, mesh selectivity, and catches in the multi-species bottom trawl survey of the sGSL. The data and indices are reported for the whole-area for the spring spawners, and regionallydisaggregated (North, Middle, and South regions) for the fall spawners where applicable. Spring spawners were assessed using a statistical catch at age (SCA) model that allowed for time-varying catchability to the gillnet fishery and time-varying natural mortality. The model estimated that spawning stock biomass (SSB) has been in the critical zone of the Precautionary Approach framework since 2002. The SSB median estimate in April 1 2020 is estimated to be approximately 26,000 t; 55 % of the limit reference point (LRP = 47,250 t). Under current low recruitment and high natural mortality conditions, this stock is not expected to recover in the short or the long term. Reducing fishing mortality only slightly reduces the probabilities of SSB decline in projections. By 2029, the probability of exceeding the LRP was 0 % at all catch levels, with SSB values ranging between 160 and 1,198 t. Fall spawners were assessed as regionally-disaggregated populations using a SCA model that allowed for time-varying catchability to the gillnet fishery and time-varying natural mortality. Estimated SSB has been declining in all three regions in recent years and is currently in the Cautious Zone of the Precautionary Approach framework. At the target catch level in 2019 (16,000 t), the probabilities of a 5 % increase in SSB by 2022 are 29 %. Long-term projections show a continuous decline, with SSB in the Critical Zone by 2025. As a consequence of low productivity and high natural mortality, exploitation of this stock should assert caution until high recruitment is observed for consecutive years. The catch level offering the greatest probabilities of increasing SSB in the short and long term was 2,000 t. [ABSTRACT FROM AUTHOR]

The 2019 assessment of the southern Gulf of St. Lawrence (sGSL) snow crab, Chionoecetes opilio, stock (Areas 12, 19, 12E and 12F) is presented. Snow crab in the sGSL is considered as a single stock unit for assessment purposes. The 2019 assessment was conducted as per the recommendations of the Snow Crab Assessment Methods Framework Science Review held in November 2011. The catchability for commercial-sized adult male snow crab in the snow crab bottom trawl survey is assumed to be constant over the time series and equal to one. The snow crab indices from the 2019 trawl survey are likely positively biased, resulting from a change in vessel and trawl fishing procedures in 2019. The trawl may have been fishing and catching snow crab over a larger area than estimated using the standardization procedures in this assessment. For the purpose of the assessment, the estimates of the commercial biomass and all abundances of males and females presented here have not been corrected according to this bias. The exploitation rate of the 2019 fishery in the sGSL was 39.3 %. The 2019 post-fishery survey biomass of commercial-sized adult male crabs was estimated at 79,066 t (95 % confidence intervals 69,072 to 90,091 t), which is similar to 2018 (80,746 t). The available biomass for the 2020 fishery, derived from the 2019 survey, is within the healthy zone of the Precautionary Approach (PA) Framework. The residual biomass from the 2019 survey was estimated at 20,291 t, a decrease of 5.3 % compared to the 2018 survey estimate (21,432 t). Seventy-five percent (75 %) of the 2019 survey biomass, available for the 2020 fishery, is composed of new recruitment (58,995 t). The recruitment to the commercial biomass from the 2019 survey is similar to 2018 (59,609 t). Based on the agreed harvest decision rule, the point estimate of the biomass in the 2019 survey of 79,066 t corresponds to an exploitation rate of 40.6 % and a total allowable catch of 32,101 t for the 2020 fishery. At this harvest level, there is zero chance of residual biomass post-fishery in 2020 being in the critical zone. A risk assessment to attainment of PA objectives of potential positive biases in the 2019 commercial biomass estimate is provided. Despite the possible overestimation concerns of the 2019 assessment, the biomass of commercial-sized adult males is considered to be at a high level and in the healthy zone of the PA. There is a broad distribution of snow crab in the sGSL and continued positive signs of sustained recruitment and high female abundances. [ABSTRACT FROM AUTHOR]

Although the management of fish spawning aggregations (FSAs) often requires a precautionary approach that initially emphasizes conservation, understanding the dynamics of spawning and interactions with fishing activities can help identify long-term management solutions that balance conservation with utilization. We designed a parsimonious, per-recruit model to evaluate the potential effects of seven time-closure scenarios implemented during the spawning season on egg-production-per-recruit (EPR; a conservation metric) and yield-per-recruit (YPR; a fisheries metric) of Gulf corvina (Cynoscion othonopterus), a vulnerable marine fish that experiences persistent overfishing at its only known spawning grounds in the Gulf of California, Mexico. Five of seven scenarios provided measurable increases in EPR (11–48%) and were accompanied by proportional increases in YPR (29–36%) that resulted in a sustainable fishery. Increased mortality of juveniles and small adults through targeted fishing or as bycatch in other fisheries, however, would erode both the fisheries and conservation benefits of these time closures. Our results demonstrate that information on spawning and fishing activities can be combined with stakeholder input to identify regulations that permit the sustainable harvesting of FSAs. Furthermore, the implementation of brief, temporal fishing effort restrictions can represent a viable, less restrictive alternative to marine protected areas for the management of FSAs. [ABSTRACT FROM AUTHOR]