Growth and age of Atlantic saury, Scomberesox saurus saurus (Walbaum), in the northeastern Atlantic Ocean

Abstract

The Atlantic saury Scomberesox saurus saurus (Walbaum) is a widely distributed epipelagic nekton species in the north Atlantic. It is considered one of the most abundant small pelagic species in the north Atlantic and is of increasing interest to commercial fisheries in American and European countries.Ageing of Atlantic saury is difficult, annual marks in otoliths, scales and other structures are often not present or are difficult to interpret, resulting in non-robust estimations.Growth of the Atlantic saury, from the northeastern Atlantic Ocean was studied by examining otoliths and scales for the presence of putative annual and daily growth marks. A description of Atlantic saury saggital otolith microstructure is given. No annual structures were observed on scales or otoliths. Counts of otolith micro-increments suggest that Atlantic saury exhibit a much faster growth rate than previously reported. Micro-increment counts ranged from 113 to 258 in fish from 110mm to 288mm of body size, suggesting that Atlantic saury is a short lived species. Assuming that otolith growth increments are deposited at a rate of one per day, average growth rates from hatching up to eight months old exceeded 1mm/day. The saury population available for exploitation in the northeast Atlantic is dominated by fish that are most likely less than one year old. Management of short-lived, forage species require special considerations and represents a challenge to fishery science.