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Fisheries and the impact of fishing on marine ecosystems

Sustaining fisheries and protecting marine biodiversity and ecosystems

Fishing is both a highly valued economic, cultural, and recreational activity and a pressure on marine wildlife and marine ecosystems. Our reporting programme had insufficient data from which to draw firm conclusions about the full ecological impact of commercial, recreational, and customary fishing.

Fishing and aquaculture play important roles in the Māori economy and Māori ways of life. More generally, fishing and aquaculture contributed $896 million (0.4 percent) to New Zealand’s gross domestic product in 2013, providing over 47,000 jobs. In addition, as many as one-third of New Zealanders fish, dive, or harvest shellfish to feed family and friends.

Seabed trawling and dredging are the most destructive fishing methods, causing major damage to seabed habitats and species. Most fishing methods result in the accidental death of non-target species, including fish, sharks, rays, seabirds, fur seals, sea lions, and dolphins. Fishing can disrupt the natural balance of species within the wider marine ecosystem.

New Zealand’s commercial fisheries are managed by a quota management system (QMS) that sets levels of allowable commercial catch for the purpose of ensuring the continued viability of fish stocks over time. Recreational fishing is a pressure on coastal waters, particularly near our most populated urban centres.

Key findings

Seabed trawling and dredging for fish and shellfish have decreased

  • The number of commercial trawl tows in New Zealand waters has decreased more than 50 percent since 1995. The number of dredge tows has decreased 83 percent over the same period. We do not have data on recreational dredging. We do not know how fast or to what extent New Zealand’s seabed habitats that have been subject to trawl and dredge tows recover.

In 2015, 17 percent of New Zealand’s commercial fish stocks were overfished, requiring active intervention to rebuild stock

  • In 2015, 17 percent of the New Zealand fish stocks were overfished – meaning they were depleted and needed active management or had collapsed and needed to be closed.
  • The status of some fish stocks in the QMS are not known but knowledge of the status of fish stocks making up most of the main commercial species has improved since 2009.
  • Seventy-eight percent of total landings of fish in 2015 came from fish stock of known status (assessed against a specific management limit).
  • The 17 percent of overfished New Zealand fish stocks compares with an estimated 29 percent of fish stocks overfished worldwide.