Managing bottom trawling on the high seas

In May 2008 measures were introduced to manage the impacts of bottom trawling by New Zealand vessels on the high seas.

In 2006 the UN General Assembly called for better management of bottom fishing in the high seas. In response, the SPRFMO adopted a set of interim conservation and management measures in 2007. New Zealand’s first step has been to protect vulnerable marine ecosystems (VMEs), such as coldwater corals and sponge fields, from adverse effects caused by bottom trawling.

The Ministry of Fisheries has mapped where bottom trawling occurred during 2002-2006. Fishing outside of this ‘footprint’ is prohibited. The footprint is further divided into lightly, moderately or heavily trawled areas according to the bottom trawling that took place in this period.

To protect the VMEs the largely pristine, lightly trawled areas have then been closed, together with representative parts of the moderately and heavily trawled areas. These closures amount to 41 percent of the entire footprint; around 112,000 square kilometres in the South Pacific area.

In open, moderately trawled areas, bottom trawlers are required to move on five nautical miles whenever evidence of a VME is encountered. The interim measures also make it mandatory for all high seas bottom trawlers to have a Ministry of Fisheries observer onboard.

New Zealand will review these measures in 2010.

Work is now underway on how to include footprint mapping and observer coverage for other bottom fishing methods such as long-lining and drop/dahn-lining; impact assessments; stock sustainability measures; and catch or effort restrictions.