The growth and population dynamics ofOctopus insularistargeted by a pot longline fishery in north-eastern Brazil

• DOI: 10.1017/s0025315421000898
• Publication Date: 2022-01-28T11:50:20Z
• Authors: B.B. Batista; H. Matthews-Cascon; R.A. Marinho; E. Kikuchi; M. Haimovici
• Keywords: Cephalopod

Abstract The population dynamics of the stout reef octopus, Octopus insularis fished with longlines pots in mid-shelf waters north-eastern Brazil was studied based on fishermen's logbooks and onboard monthly fishing trips from September 2009 to August 2010. Specimens marked oxytetracycline kept tanks for up 21 days provided evidence daily deposition growth increments lateral wall upper beaks. Sampled specimens weighed 50–1280 g had 43–172 increments. Compared congeneric species higher latitudes, O. grows faster has a shorter longevity tropical environment. Total catches catch-per-unit effort were substantially dry season, less wind cooler temperatures. presence larger seasonal, correlated chlorophyll-a levels recorded six months earlier. year-round mature females males, spawned females, egg masses attached pots, considered migration small young coastal areas towards 20–40 m depth range reproduction. Annual landings attained ~200 tonnes (2005–2010). Although recent landing statistics are missing, fishermen interviewed 2021 claimed that fishery still profitable. It is suggested that, despite lack management, fast growth, reproduction limited market this relatively prevented collapse reinforces current view high resilience cephalopod fisheries.