Age, Size, and Sex information of the four-rayed rattail <i>Coryphaenoides subserrulatus</i> from the Chatham Rise, New Zealand

Population dynamic of bycatch from deep-sea fisheries are largely unexplored, due to having little or no commercial value. This study examines the age-based growth parameters of the four-rayed rattail <i>Coryphaenoides subserrulatus</i> from the Chatham Rise, New Zealand. Specimens were collected as bycatch from four trawl stations during an orange roughy (<i>Hoplostethus atlanticus</i>) stock assessment. Age determination was conducted using transverse otolith sections, with results revealing a lifespan ranging from 2 to 27 years. The study identified sex-specific differences in growth, with females reaching larger size at equivalent age than males. The sampled population was female dominated with a sex ratio of 1.66 females to 1 male. Von Bertalanffy growth function analysis showed asymptotic lengths of 345.69 mm for females and 284.8 mm for males. Annual mortality rate was estimated at 15.02% (yr^-1), indicating a stable population under unfished conditions. <i>This study provides a comprehensive population dynamics profile of C. subserrulatus in New Zealand waters</i>, contributing valuable information to the ecology of a deep sea bycatch species.