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This paper identifes reference points for Dungeness Crab in Crab Management Areas I and J in British Columbia. We estimated an Upper Stock Reference (USR = 0.456 female standardized CPUE) and a Limit Reference Point (LRP = 0.228 female standardized CPUE), as described in A Fishery Decision-Making Framework Incorporating the Precautionary Approach (DFO 2009) also known as DFO's Precautionary Approach (PA) policy. These reference points will inform the assessment of stock status of Dungeness Crab in Crab Management Areas (CMAs) I and J. Candidate reference points were estimated using three methodologies: a data-driven empirical method, a model-based method which estimates the stock-recruitment relationship, and a simulation model-based method. We recommend applying the empirically-based methodology for determining reference points for the Dungeness Crab in CMAs I and J as they are more interpretable than the simulation model-based reference points, and are more estimable than the stock-recruitment reference points. Subsequent research can use this framework to develop reference points for Dungeness Crab in other CMAs. [ABSTRACT FROM AUTHOR]

The status of the Snow Crab (Chionoecetes opilio) resource surrounding Newfoundland and Labrador (NL) in Northwest Atlantic Fisheries Organization (NAFO) Divisions (Divs.) 2HJ3KLNOP4R is assessed using a variety of metrics. Data from multi-species bottom trawl surveys conducted during fall in Divs. 2HJ3KLNO and spring in Divs. 3LNO and Subdiv. 3Ps are examined to provide information on trends in biomass, recruitment, production, and mortality over the time series. Multi-species trawl survey indices are compared with other relevant indices toward inferring changes in resource status for 2019 and beyond. These other indices are derived utilizing data from harvester logbooks, at-sea observers, the dockside monitoring program (DMP), and inshore and offshore trap surveys, as well as oceanographic surveys. Snow Crab landings remained near 50,000 t from 2007 to 2015 but have since steadily declined to a two-decade low of 27,700 t in 2018. Overall effort remained at approximately 3.5 to 4.5 million trap hauls per year over that time. Overall catch per unit effort (CPUE) was at a time-series low in 2018. Despite modest increases in the past two years, the trawl survey exploitable biomass index has remained at its lowest level for the past four years. Meanwhile, the trap survey index has declined by nearly 60% in the last two years to a time-series low. Despite modest increases in some divisions in the past two years, overall recruitment into the exploitable biomass will remain low in most divisions in 2019. Total mortality in exploitable Snow Crab is estimated to be near time-series' averages in most divisions. It has declined from very high levels in most divisions during the past two years, with the exception of Division (Div.) 3K, where it remains at a time-series high. Exploitation rate indices were at or near time-series highs in most divisions in 2017. In 2018, exploitation rates subsequently increased to a new high in Div. 3L Inshore, remained high in Divs. 2HJ3KLNO, and declined to be near or below long-term average levels in Divs. 3Ps and 4R3Pn. Elements of the Precautionary Approach Framework presented in this assessment are tentative. Limit Reference Points defining the critical zone have been established by a peer-reviewed Science process, but Upper Stock Reference lines defining the cautious and healthy zones remain under development. In 2019, most divisions are projected to fall within the cautious zone of the proposed Precautionary Approach Framework. Div. 3L Inshore would be in the critical zone. These projections assume status-quo landings. The thermal habitat index (defined as the areal extent of <2°C bottom water) has returned to near-average conditions in all divisions in recent years. Broad-scale climate indices appear favourable for improved recruitment to occur in most major areas of the stock range over the next few years. Ecosystem conditions in the NL Bioregion are indicative of an overall low productivity at the lower trophic levels (phytoplankton and zooplankton) in recent years with changes in zooplankton community structure potentially impacting the transfer of energy to higher trophic levels. A sharp decline in male size-at-maturity (i.e., terminal molt size) in most Assessment Divisions (ADs) in recent years will dampen short-term prospects for recruitment into the Snow Crab exploitable biomass. [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]