Loligo forbesii, Veined Squid

Loligo forbesii is one of the two Loligo species of significant fishery importance in Europe. It is common around the UK and its range extends to the southern end of the Iberian Peninsula, also including the Mediterranean and the Azores islands. In the northern part of its range, fishery landings of long-finned squid are almost exclusively L. forbesii but off the Iberian Peninsula and in the Mediterranean, L. vulgaris is the more important resource species. The population in the Azores is thought to be a separate sub-species. It follows a typical loliginid annual life cycle, with the winter breeding cohort usually the most important, although summer breeders are known from various time-periods and locations so there may be two recruitment and spawning periods, as well as some animals of all maturity stages present throughout the year, reflecting high variability in the timing of the life cycle and sensitivity to environmental conditions. Paralarvae are planktonic but switch to a demersal lifestyle as juveniles. Individuals may live up to 15-16 months old. Males exhibit at least two alternative growth strategies, with smaller (slower growing) and larger animals probably corresponding to "sneakers" and "mate-guarders" on the spawning grounds. Females are intermittent terminal spawners, probably producing up to around 23 000 eggs. The distribution is mainly over the continental shelf but egg masses (attached to the substrate) are known from depths over 700 m. Distribution is also related to temperature and salinity. The species apparently exhibits typical ontogenetic migrations, with juveniles moving offshore to feed and adults moving inshore to spawn, although spawning grounds are still not well-known and some migratory movements seem to be parallel to the coast. L. forbesii is an active predator, taking a range of crustaceans and fish (the diet shifting towards more and larger fish as the animals grow) with some cannibalism. They are eaten by a wide range of marine predators, from fish to marine mammals and are thought to have an important role in ecosystem function. Abundance is very variable year to year and this is reflected in fishery catches. There is some directed fishing, based on trawling in the north and jigging in the south but most landings are by-catches from trawlers. Most UK catches are exported to the south of Europe where there is a longer tradition of eating squid. As for all cephalopods in European waters, there is no routine stock assessment and little management of the fishery and current routine fishery data collection is not adequate to support stock assessment. In the future, management options which are likely to be feasible include protection of spawning areas and avoidance of fishing on very small recent recruits. © 2013 by Nova Science Publishers, Inc. All rights reserved.