Science Advisory Report 2019/060

Assessment of lobster (Homarus americanus) in the Gaspé (LFAs 19-21), Quebec, in 2018

Summary

• Landings are up sharply and reached a record 2,509 t in 2017, followed by a decline to 2,315 t in 2018 associated with Right Whale conservation measures. Landings in 2018 were 26% greater than in 2015 and 116% higher than the historical average (1993-2017). Fishing effort has decreased slightly since 2009 and is below the 1994-2004 level. In 2018, 78% of Gaspé landings came from LFA 20, 10% from LFA 21 and 12% from LFA 19.
• For the entire Gaspé area, the catch per unit effort (CPUE) in weight from commercial sampling rose sharply from 2015 to 2018. In LFA 19, the CPUE by weight in 2018 was 60% higher than in 2015 and 202% higher than the historical average (2001-2017). In LFA 20, the CPUE by weight in 2018 was 59% higher than in 2015 and 133% higher than the historical average. In LFA 21B, the CPUE in the fall of 2018 was 74% higher than in 2015 and 162% higher than the historical average (2001-2017). The logbook CPUEs follow the same trend.
• In LFAs 19 and 21, demographic indicators showed that the average size of commercial lobsters was large in 2018 (95.8 mm and 92.8 mm respectively), but 4% lower than in 2015, possibly due to increased recruitment. In LFA 20, the average size of commercial lobsters has changed little since 2008 (≈ 88 mm). Commercial lobster size structures are much wider in LFAs 19 and 21 than in LFA 20.
• Fishing pressure indicators could not be estimated for LFAs 19 and 21. In LFA 20, exploitation rates were lower between 2015-2017 (76%) than between 2011 and 2014 (81%) but remained very high.
• Productivity indicators were high in LFA 20. The abundance of berried females has continued to increase since 2011. Theoretical egg production was 8.6 times higher in 2018 against to 4.6 times higher in 2015 compared to the period 1994-1996. In 2018, the abundance of prerecruits increased by 16% compared to 2015 in LFA 20, suggesting that landings may continue to increase. This information is not available for the other LFAs of the Gaspé.
• High abundance, productivity and landings indicate that the Gaspé lobster stock is in good condition and in the healthy zone according to the precautionary approach. In recent years, indicators have remained the same or improved based on prevailing environmental conditions and exploitation levels. However, in LFA 20, the small average size of commercial lobsters suggests that actions on reducing fishing effort must be pursued. Considering the environmental changes, it would be important to rapidly develop or update the biological knowledge essential for the sustainable management of these stocks.

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.