Story: Marine conservation

Page 5. Fisheries

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Laws

New Zealand’s first fisheries legislation was applied to oyster fisheries in 1866. Protection for finned fish, such as closed seasons and limits on the mesh size of nets, was established with the Fish Protection Act 1877. These measures were eventually combined under the Fisheries Act 1908.

The aim was to manage fish and shellfish stocks for future catches, rather than to conserve species for their intrinsic value. If something made good eating but stocks were dwindling, legislation could help ensure it would be eaten in the future as well. When stocks recovered, regulations were relaxed. This was essentially the ethos of fisheries management until 1986.

The 1986 quota system

In 1986 annual quotas, or limits, were set for catches of different species. The intention was to manage fish stocks at levels that ensured there would be future harvests. Since 1986 more fish and shellfish species have been included in the quota system. For example, quotas were set for two pāua species in 1986, for the rock lobster in 1990 and for kina in 2002. The quota system still underpins New Zealand fisheries management and is highly regarded internationally.

Fisheries Act 1996

The Fisheries Act 1996 required the protection not only of fisheries, but also of dependent species, aquatic biodiversity and habitats. The act also introduced charges, such as the conservation services levy, with which the fishing industry must fund research into the impacts of fishing on protected marine wildlife.

In the early 2000s no fish species (except the spotted black groper) were protected; they could be taken as long as commercial or recreational fishers complied with fisheries regulations (such as size and daily bag limits). Commercial fishing enterprises were also required to hold a quota allowance. In general, the only places where fish cannot be taken are marine protected areas.

Bans

Some fish and shellfish in certain areas are also protected by Ministry of Fisheries bans, which allow stocks to recover from overfishing. As an example, the Wellington pāua fishery has been closed to commercial harvesting since 1974.

Safeguarding seamounts

Seamounts are undersea mountains, usually of volcanic origin. In New Zealand’s Exclusive Economic Zone there are at least 500 seamounts. Under the Fisheries Act 1996 the Ministry of Fisheries can prevent fishing in high-risk areas, where the effects of fishing are largely unknown. In 2001 it did just this, closing 19 seamounts to trawling. The shallowest of these peaks (220 metres) is known as Rumble III, an active volcano north-east of the North Island. The deepest peaks are the unnamed Seamount #140, north-west of Cape Rēinga, and Seamount #328, south-east of the Chatham Islands; both are 1,750 metres down. These were the first protected deep-water areas in New Zealand’s fishing grounds.

Environmental groups accuse the fishing industry of destroying the sea floor by bottom trawling. In this form of fishing, heavy nets with rubber wheels are dragged along the sea floor, damaging the marine life and the seabed in their path. Scientists estimate that it might take decades or even centuries for some of the cold-water corals and sponges to recover.

Reducing by-catch

Species that are accidentally killed in nets are called by-catch. Sea lions are found in squid nets, diving seabirds are taken on longline hooks, and less commonly, dolphins are caught in coastal set nets. Numerous other species also die from entanglement in nets.

Technological improvements are helping to reduce by-catch. Exclusion devices on trawl nets help to release seals, sea lions and turtles. Echo sounders can locate schools of hoki, a commercially trawled species, in mid-water so that trawlers do not have to drag the ocean floor. Net monitors tell skippers when their nets are full, so that they can haul them in before unwanted species are caught.

Fishermen must pay penalties if they catch too many individuals of a species for which they have no quota.

How to cite this page:

Gerard Hutching and Carl Walrond, 'Marine conservation - Fisheries', Te Ara - the Encyclopedia of New Zealand, http://www.TeAra.govt.nz/en/marine-conservation/page-5 (accessed 24 October 2019)

Story by Gerard Hutching and Carl Walrond, published 12 Jun 2006, updated 1 Sep 2015