Forecasting American lobster fishery recruitment in Atlantic Canada using benthic recruitment densities

Abstract

Since the 1980’s Atlantic Canada has seen a dramatic increase in lobster landings. There is limited understanding of the mechanisms underlying these changes, and an even lesser ability to forecast future changes. I built an individual-based model for three regions that relates the annual number of benthic recruits in nursery grounds to lobster landings up to seven years in the future, using latitude-based von Bertalanffy growth equations complemented with inter-individual variability in growth. I found significant positive relationships between the modelled recruitment index and fisheries landings in all regions. Out-of-sample model validation provided mixed results, but it is unclear to what extent this reflects model errors versus the limited number of years available to build these reduced models. My findings indicate that benthic recruitment indices could help make strategic decisions concerning fishing activities and they argue for the continued (or expanded) monitoring of early life stages of lobster in Canada.