Common Commercial Fish Species - A - G
In New Zealand, albacore form the basis of a summer troll fishery, primarily on the west coasts of the North and South Islands. This fishery accounts for a large proportion of the albacore landings. Albacore are also caught throughout the year by longline (1000–2500 t per year). Total annual landings over the past 10 years have averaged 5422t (maximum landing 6574 t in 2002-03).
Both species of Beryx occur throughout the world's tropical and temperate waters, in depths from 25 to 1200 m. In New Zealand waters most "alfonsino" landings are of alfonsino B. splendens and landings of the red bream B. decadactylus account for less than 1% of this catch. These species are primarily associated with undersea structures such as the seamounts that occur off the lower east coast of the North Island and on the Chatham Rise, in depths from 300-600m.
Average size is 30-50 cm. Alfonsino have a maximum recorded age of 17 years and females grow faster than males.
Bigeye Tuna (BIG)
Bigeye tuna are epi-pelagic opportunistic predators of fish, crustaceans and cephalopods generally found within the upper few hundred meters of the surface. Tagged bigeye tuna have been shown to be capable of movements of over 4000 nautical miles over periods of one to several years. Juveniles and small adults school near the surface in tropical waters while adults tend to stay deeper. Adult bigeye reach a maximum size of 210 kg and maximum length of 250 cm.
Blue Shark (BWS)
Blue shark are one of the most widespread shark species in the world and, in New Zealand, are likely to belong to a single, large, wide-ranging stock probably comprising the entire South Pacific, and possibly even including the North Pacific and Indian Oceans. Studies show that blue sharks grow fast initially, reaching about 200 cm TL within five years of birth. Age at maturity is about 4–6 years for males and 5–7 years for females. The oldest blue shark aged was 16 years, and a shark that was 151 cm TL at tagging.
The cockle is a shallow-burrowing suspension feeder of the family Veneridae. It is found in soft mud to fine sand on protected beaches and enclosed shores around the North and South Islands, Stewart Island and the Chatham Islands. Suspension feeders such as A. stutchburyi tend to be more abundant in sediments with a larger grain size.
Dredge Oysters (OYS)
Tiostrea chilensis is endemic to New Zealand. This species is widely spread throughout New Zealand usually as small beds on sandy mud in harbours and bays. It is most abundant in Foveaux Strait, from 25 - 50m.
Average shell length is 6-8 cm, reaching 10 cm. It has been found that there was evidence for strong seasonal variation in growth, with mean growth over the winter was zero or even slightly negative (the latter presumably due to shell abrasion). Growth rates vary between years and between areas. They recruit to the legal-sized population (a legal-sized oyster will not pass through a 58 mm diameter ring, i.e., it must be at least 58 mm in the smaller of the two dimensions of height or length).
Gemfish are widespread around New Zealand occuring on the continental shelf and slope, from about 50-550 m depth. Gemfish also occur off southern Australia and Japan.
Average size 60-90 cm, reaching 110cm. Both sexes display similar growth rates until age 5, but subsequently, females grow faster. The maximum ages recorded for northern gemfish was 17 years for both sexes and, for southern gemfish, 17 for males and 15 for females. In the northern fishery (SKI 1, SKI 2), males and females appear to recruit into the fishery from age 3 but are probably not fully recruited until about age 5 (SKI 2) and age 7 or 8 (spawning fishery in SKI 1). In the southern fishery, gemfish start to recruit at age 2 into spawning and non-spawning fisheries but age at full recruitment was difficult to determine.