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Snapper:
everyone's favourite fish
Preview
Snapper is a popular fish, prized by Maori, commercial and
recreational fishers alike. However, the resource has been
overfished to the extent that by the early 1980's its future
was in doubt. However overall, the decline in snapper fisheries
appears to have been halted, but in some areas, for example
the Hauraki Gulf, snapper are still under pressure. There
are now management plans in place to allow the stocks to increase.
Vital statistics
Distribution,
habitat and fisheries
Snapper mostly live in shallow water (10-50 metres), although
they are also found down to depths of 200 metres on the continental
shelf of the North Island and northern South Island. There
are at least six separate stocks. Fish on the east coast grow
more slowly and are generally smaller than those on the west
coast and in Tasman Bay/Golden Bay.
Coastal
areas with a clear ocean floor are home to most snapper. But
snapper can also be found near rock bottom areas, in harbours,
bays, around offshore islands, and sometimes a moderate distance
offshore.
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Generally
snapper populations contain individual fish of widely varying
age. However, young snapper tend to swim in schools of the
same size and year group, while older snapper often live alone.
Snapper
movements are not well understood. Some young school snapper
migrate hundreds of kilometres, whereas others stay in the
same area. Main movements seem to be seasonal. Adults move
to spawning grounds in spring, and inshore to feed in late
summer. Some fish move offshore to warmer water in winter.
Food
Snapper are carnivores. Small snapper feed mainly on small crustaceans
and worms. Larger snapper eat fish and larger, harder-bodied
animals such as sea eggs (kina), crabs and shellfish. Snapper
are very adaptable and if one type of prey becomes scarce they
can change their eating habits.
Age,
growth and mortality
Snapper are relatively long-lived and slow growing. They have
been known to live to at least 60, grow to a length of 100
cm and weigh 17 kg or more.
In the
Hauraki Gulf, where most research on snapper has been done,
snapper reach sexual maturity at three to five years of age
when they are 22-30cm long. They breed between October and
February, depending on the water temperature. Each fish may
spawn daily over extended periods, releasing up to 100,000
eggs each time.
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Spawning
success is less related to the number of parent fish than
to conditions at spawning time and during the months following.
Warm summer to autumn temperatures appear to allow a greater
survival of eggs, larvae and juveniles. After a series of
warm years the fishable stock will increase, with a time lag
of four to five years (the time from spawning to full recruitment
as adults). After cool years the stock level will decline.
The eggs
(which hatch in 1-2 days) and the larvae are very vulnerable
and the mortality rate can be 90 percent or more. Young fish
may also have a high mortality rate during their first few years
but older fish have a mortality rate of about 10 - 15 percent
per year, mainly due to fishing and natural causes.
Commercial
importance
Commercially, snapper is one of New Zealand's most important
fish. It has been fished heavily for years, and as a result,
stocks in several areas are considered to be below their most
productive levels.
Snapper
is New Zealand's most valuable coastal fish species. In addition
to local sales, about $50 million worth of snapper was exported
each year in the late 1980s and early 1990s. In the late 1990's
this fell to around $40 million.
The main
market for snapper is Japan, which mostly takes chilled whole
fish, and an increasing amount of live snapper. High prices
for iki jime (literally meaning "stab death") fish
are fetched, which requires live fish to be killed by a spike
driven through the brain. Australia
is also an important market for snapper.
None of
these methods managed to stop overfishing. Concern about overfishing
was one of the reasons behind the introduction of the Quota
Management System.
Traditional
Maori fishing
Snapper (tamure) are very important to Maori in northern New
Zealand. They form part of their oral tradition and there are
large deposits of snapper bones in the middens of prehistoric
fishing camps.
 In
the early 1980s there was a New Zealand-wide moratorium on
new entrants to the commercial fishery, followed by removing
licences from part-time fishers. These measures had an impact
on northern Maori fishers.
The situation
was made more difficult for some Maori Fishers in 1986, when
the Quota Management System gave quota to full-time fishers
on the basis of their catch history. Some of these fishers
did not live in the Northland area, but travelled there to
catch fish from Auckland or Tauranga.
Fishers
without permits missed out on quota. This was one of the reasons
why Maori lodged the Muriwhenua claim for control over fisheries
north of Doubtless Bay.
Recreational
fishers
Snapper are highly valued by recreational fishers. Surveys in
1991 - 1994 and again in 1996 estimated that about 3,500 tonnes
of snapper are caught annually by recreational fishers.
Recreational
fishers use lines, beach seines and set nets on a small scale.
The proportion of total snapper taken by recreational fishers
varies between 10 and 40 percent.
Commercial
fishers
Commercial fishers use longlines, beach seines and set nets,
Danish seiners and trawlers. Purse seiners are now banned
for snapper.
Fisheries
There are four major and two smaller snapper fisheries. The
four major fisheries are: the Hauraki Gulf, eastern Northland,
Bay of Plenty and the west coast of the North Island. The
smaller fisheries are East Cape/Hawke's Bay, Tasman Bay and
Marlborough Sounds.
The
Hauraki Gulf
The Hauraki Gulf is the largest snapper fishery for both recreational
and commercial fishers. Recreational fishers, including charter
boats catch many fish but this is allowed for under the Total
Allowable Catch (TAC). In 1992 the amateur bag limit was reduced
from 30 to 20 a day.
Snapper
landings into Gulf ports have ranged from 3,000 tonnes to
8,000 tonnes, about two-thirds of this coming from the Gulf
itself. The landings peaked at 8,400 tonnes in 1971, but declined
to 3,400 tonnes in 1986.
When
the Quota Management System was introduced in 1986, the snapper
TAC in Zone 1 (which combines eastern Northland, the Hauraki
Gulf and Bay of Plenty) was set at 4,700 tonnes to allow the
fishery to rebuild. Many fishers made successful appeals to
the Quota Appeal Authority. By 1991, the Total Allowable Commercial
Catch (TACC) had risen to more than 6,000 tonnes.
The total
fishing pressure was considered too high to allow the stock
to rebuild, and in 1992, in an effort to address this problem,
the TACC was reduced to 4,900 tonnes. A further reduction
to 4,500 tonnes was made in 1997.
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