Species Focus - Coromandel Scallops (Pecten novaezelandiae)
The Coromandel Scallop fishery extends from Cape Rodney near Leigh in the
north to Town Point in the Bay of Plenty in the south.
This area provides a fertile environment for scallops, with scallop
beds found throughout much of this range.
Scallops in this area have long been popular with recreational and
customary fishers who take their catch by diving, dredging or on
occasion, by hand-gathering scallops washed-up after a storm.
A commercial dredge fishery developed in the late-1960s and
early-1970s. At its peak during the early 1990s, this fishery
supported 22 commercial fishers with landings in excess of 200
tonnes meatweight (the weight of the edible part of the scallop).
Status of the Stock
Like many other shellfish species,
scallops are very sensitive to
environmental conditions such
as sea temperature, currents
and availability of food. This
means that scallop recruitment
(the number of new scallops in
the fishery each year) is highly
variable and difficult to predict in
advance. Because of this, scallop
numbers can fluctuate significantly from
year to year. To ensure that fishing is always
at sustainable levels, the Coromandel scallop
fishery is managed differently to most other
fisheries in New Zealand.
In 2002, the total allowable catch in the fishery was set at 48
tonnes (meatweight), with the total allowable commercial catch
set at a deliberately low ‘baseline’ level of 22 tonnes.
The baseline can be reviewed and increased each year only after
a survey has shown that a higher catch level would be sustainable.
In this way, the catch limit in any given year is set at a sustainable
level in response to the natural variations in scallop numbers in the
Commercial and non-commercial fishers generally fish different
areas within the Coromandel Scallop fishery. Non-commercial
fishers may fish anywhere within the fishery, though most of their
effort is concentrated in the shallower areas closed to commercial
fishers. In contrast, commercial fishers have tended to fish almost
exclusively in the established beds around Little Barrier Island,
Waiheke Island, Mercury Bay, Waihi and Motiti.
Current Management Issues
Coromandel scallop distribution and management areas.
In 2005, MFish selected this fishery to test the concept of fishery
plans. This saw MFish bring together fishers from the commercial,
recreational and customary sectors, as well as representatives
from the environmental sector to discuss what each wanted to
see achieved in the fishery. Over the following 18 months, this
group worked together to produce the Draft Coromandel Scallop
Fishery Plan. This document combines many different goals and
aspirations, including a desire to increase the stability of the fishery
and to “maintain the mauri and sustainability of the fishery with a
cautious respectful approach.”
In 2008, MFish intends to work with stakeholders and tangata
whenua to develop this plan further and seek wider public
comment. For more information and a copy of this draft plan
see the MFish website.
Historically, an annual survey has been undertaken on the
commercial beds only. However, for the past three years, four
popular recreational beds in the Coromandel fishery have also
been surveyed. It is hoped that this work will help provide more
accurate estimates of total scallop abundance in the fishery.
It should help us to find out if there is a relationship between
scallop abundance in the commercial beds and in the non-commercial
areas of the fishery.
Scallop catch limits and allowances
Over the past few years, this stock has been fished cautiously by
the commercial sector, with annual commercial landings seldom
exceeding 50 percent of the available yield. For example, in 2007
the stock assessment survey indicated that 338 tonnes was
available from the commercial beds, yet commercial fishers opted
to take only 108 tonnes of scallop.
Recent changes to non-commercial regulations in this fishery
include an allowance for divers to harvest the daily bag limit for
up to two boat safety people and a shift in the recreational scallop
season which now runs from 1 September to 31 March.