|Sea breams occur in all oceans but only one species, the snapper, is found in NZ. These fishes are all medium to large, living from animals found on or in the sea bottom. Most sea breams undergo sex change at some stage in their lives. They are good seafood.|
The family Sparidae or sea breams (also called porgies) contains some 40 species, distributed throughout tropical and subtropical waters of the world, (Eocene to present). They resemble the fishes from the families Lutjanidae (true snappers) and Nemipteridae. Their mouths are small but with powerful teeth and molars, used in crushing crustaceans and molluscs. About 100 species are known from shallow seas of tropical, subtropical and temperate zones. Most species are less than 30cm long, a few up to 120cm. They are important food and game fishes.
|Chrysophrys auratus (Pagrus
- snapper, tamure
(Australia has different names according to size: cockney, squire, pinky, snapper, and also red bream)
Golden sea bream: Chryso=golden (Gk: khrusos=gold);
(L: aurum=gold); pagrus=sea bream (Gk:
The common name 'snapper' was given to this fish by Captain James Cook in 1770. He mistook it for a member of the true snapper family Lutjanidae, a group of fish with which he had become familiar in American waters. Although he mistook the fish, he spelt the name correctly, whereas many subsequent writers have used 'schnapper' - an erroneous spelling of unknown origin.
No one needs any introduction to the snapper - sought after quarry of commercial and amateur fishermen and one of the most abundant of the continental shelf fishes. Mature snapper normally range in length from 30 to about 80 cm but exceptional specimens may attain a size of over 1m. Most school snapper weigh between 2 and 5 kg and the biggest individuals caught have been around 15 or 16kg but divers have occasionally reported sighting fish with an estimated weight of more than 20kg and a length of 1.3m! Because of their commercial importance snapper have been the subject of a large number of studies over the years but a full picture of their biology and behaviour has still not emerged. However, a large amount of information has been gathered and some aspects of the snapper's life are understood fairly well.
They have large and very effective teeth with sharp canines in the front
of the jaws and rounded molars further back and can pry loose and crush
almost any invertebrate. Examination of the gut contents of these fishes
has shown that they eat over 100 different species of invertebrates and
small fishes, mainly crustaceans, polychaete worms, echinoderms, and shellfish.
Snapper living in rocky reef areas feed predominantly on crabs, the common
sea urchin, and shellfish such as limpets and topshells. Snapper also feed
on pilchards and are often found underneath schooling kahawai to pick up
pieces of fish that are drifting down.
A lot of work has been done on the movement of snapper populations but many questions remain. Small fishes less than 15cm long move into shallow water during summer and out into deeper water (down to 100m) during the winter. Adults move inshore in the summer after spawning but some large solitary fish seem to be resident in shallow coastal waters all year round. Many of the immature fish less than 30cm long also appear to remain permanently over inshore rocky reef areas where they set up feeding territories and defend them against other small snapper. The extent of these seasonal movements and of the migrations to spawning grounds is not known, but being bottom-living fishes that are most abundant near rocky reef areas on the inner continental shelf they probably do not move great distances. In late summer and early autumn they are found more so inshore, whereas they move to deeper water in winter. Reef snapper appear to stay in their territories between spawning but they may travel huge distances to their favoured spawning areas. Tagged adult snapper mostly moved less than 50Km from their tagging sites but some moved several hundred Km.
An extensive series of fish counts made by divers in the Leigh area
on Northland's east coast showed that snapper was the third most abundant
of the larger fishes living on inshore rocky reefs. An average of 6700
snapper of all sizes for each kilometre of rocky coast was found in this
|Fishing: Snapper are caught commercially by a variety of methods: on set lines, with bottom trawls or pair trawls and in midwater trawls. Fishing pressure in the Hauraki Gulf and off Northland's east coast is intense and the populations in these areas are heavily overfished Over 30,000 tonnes of snapper are landed annually in New Zealand and this is the most popular eating fish both for local consumption and for export. The Chinese and Japanese word for snapper is 'tai', which also means 'good fortune'. Hence snapper is a must for every important family celebration. Caught on longlines and killed immediately by the 'ike' method, then cooled quickly in brine, while the hook is left in the mouth, these fish are flown to northern destinations within a few hours of being caught.|
Recreational fishermen take snapper by handline or rod, usually in the vicinity of reefs, wrecks or deep holes, on scallop beds or around low reef and rubble area in bays and inlets. Snapper take the bait easily and put up a good fight.
Professional fishermen recognise various different forms: dull pink
snapper for schooling fish caught far offshore above muddy grounds, deep
pink snapper found more closely inshore and brown reef snapper who spend
much of their lives on coastal reefs. 'Old man snapper' are old fish who
have developed a hump on their heads.
Very small snapper are a fawn tinged silver with darker brown vertical
bars, a pattern that changes at a length of about 15cm to pale pink with
blue tinged fins and a scattering of iridescent bright blue spots on the
back and flanks. Most adult fish are this colour as well but some extremely
large solitary specimens may become a fairly uniform dark grey, having
lost their iridescent blue spots. Spawning males usually develop dark patches
under their chins. Snapper have a number of sharp spines in their dorsal,
anal and pelvic fins, making them hard to handle with bare hands and perhaps
hard to swallow by predators.
The scales of a snapper usually show clear year rings, marking the winter months when body growth almost stops.
Fins: D XII 10;A III 8; P I 5;LL 54. Size 30-80cm. Weight up to 15 Kg.
history: Gonads become ripe in the late spring and in northern waters
these fish spawn during the summer months (Oct to Feb, peaking in Dec and
Jan) when sea surface temperatures reach over 18°C. During cold years,
snapper spawn erratically, with poor results. They are group spawners and
gather in large schools, near an entrance to an estuary or in a bay or
gulf. While rising and falling in unison in the warm surface waters each
fish releases huge numbers of eggs or sperm into the water. It has also
been observed that large groups of snapper drift lazily just below the
water's surface, barely moving, except to roll over and discharge their
gametes into the water. All fish in the group sppawn at the same time.
Snapper are serial spawners, producing many batches of gametes and spawning
several times in one season.
It is possible that the peak of this activity takes place at night, but spawning has only rarely been observed and this is not known for certain. For each fish, spawning is over within a week but the whole spawning season extends much further, moving to different areas as the sea warms up. Each fish probably spawns several times during each season. The spherical eggs, about 1mm in diameter, are externally fertilised and then float at or near the surface for one or two days before hatching.
The larvae and very young fish are presumably midwater or bottom-dwelling, since none have been taken in surface plankton hauls over known spawning grounds. The smallest snapper generally seen are about 2cm long and probably several months old. At this small size they are already perfect miniatures of the adult fish, complete with tiny blue spots along their backs. Snapper grow slowly and reach a length of 10cm at the end of their first year and do not mature until they are about 4 years old and about 30cm long. During their 3rd and 4th year, about half of them change sex, going through a hermaphroditic stage, to become males. By counting annual rings in the ear bones or otoliths it has been established that the average school snapper is between 4 and 10 years old and that some large snapper may be almost 60 years old. Growth rates vary considerably depending on local conditions of food, temperature, and the density of other snapper and a 5Kg fish may be anything between 20 and 50 years old. The oldest snapper are some 60 years old.
Growth: 1year=10cm, 2years=16cm, 3years=21cm, 4years=30cm, 5years=33cm=0.5Kg,
6years=35cm, then about 1cm per year.
This species is predominantly a northern fish, found on the continental
shelf around the North Island and in the north of the South Island. The
same species is also found in southern Australia. It is thought that the
Australian species forms a different spawning stock, with very little or
no mixing with the NZ stocks.
There is evidence of two stocks occurring in NZ, the west coast and east coast stocks, which are separated by North Cape. The two stocks are similar in body shape and colour but differ in body chemistry, indicating that there is little interbreeding. The fish on the west coast also grow faster than those on the east coast.
The greatest concentrations are found in the Hauraki Gulf, whichis also their main spawning ground.
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