Science Advisory Report 2019/061

Assessment of lobster (Homarus americanus) in the Magdalen Islands (LFA 22), Quebec, in 2018

Summary

• Landings reached a historic peak of 4,757 t in 2018, which was 91% higher than the 25-year average for a similar or lesser fishing effort. The increase in landings between 2015 and 2018 was greater in the south (40%) than in the north (31%).
• In 2018, for the Islands as a whole, the catch per unit effort (CPUE) in weight for commercial sampling was higher (69%) than in 2015 and 111% higher than the average of the historical series (1985–2017). The CPUE in number and the logbook CPUE showed a similar trend. The density of commercial lobsters in the trawl survey showed a strong increase in 2015 followed by a downward trend since then. In 2018, it was 22% lower than in 2015, but 58% higher than the historical average (1995-2017).
• The demographic indicators show that the average size of commercial lobsters sampled during the fishery has increased slightly, but in a sustained manner since the end of the legal size increase in 2003. In contrast, in the trawl survey, the average size has been decreasing for males since 2013 and relatively stable for females since 2003.
• The fishing pressure indicators show a slight decrease in exploitation rates since 2010.
• The productivity indicators remained high. For the Islands as a whole, theoretical egg production compared to the 1994-1996 period was 3.9 times higher in 2018 compared to 2.6 times higher in 2015. However, since 2015, there has been a downward trend in the proportion of post-molt females who have been inseminated.
• Fishing recruitment indicators suggest that landings will remain high for the next 2-3 years. The benthic recruitment index decreased between 2010 and 2016, which could suggest a decrease in fishing recruitment in the medium term.
• High abundance and productivity indicate that the Magdalen Islands lobster stock is in good condition and that current exploitation levels are adequate. According to the precautionary approach, the Magdalen Islands lobster stock is currently in the healthy zone.

This Science Advisory Report is from the March 12-14, 2019 regional peer review meeting on the Assessment of the lobster in Quebec’s inshore waters. Additional publications from this meeting will be posted on the Fisheries and Oceans Canada (DFO) Science Advisory Schedule as they become available.