Bottom Trawling in New Zealand

Bottom trawling is New Zealand’s most common commercial fishing method. It is very limited in its extent and is highly-regulated and monitored by industry and the government to ensure sustainable practice.

Bottom trawling is when a net is towed just above or on the bottom of the seafloor in New Zealand fishing grounds.

Fishers target popular species such as hoki, orange roughy and snapper near the bottom of the seafloor because that is where these fish are abundant.

By typically returning to the same fishing grounds each season, fishers are able to catch enough fish by bottom trawling less than three percent of our ocean territory or EEZ each year. Fishing grounds are comparable to a farmer’s fields – they are used specifically for food production and limit the effects of this production to a particular area.

New Zealand has successfully designated 30% of our ocean space as marine protected areas. These areas, which typically have high levels of ocean biodiversity, are closed to trawling.

The comparatively small area of fishing grounds mostly have sandy or muddy seafloors.

By mostly sticking to sandy and muddy seafloors, expensive fishing nets do not get caught on rocks, coral or seaweed. It also helps to minimise disturbance to the seafloor. And because the nets can be towed without snagging, less fuel is required to tow them, reducing trawling’s carbon footprint.

Technology is also increasingly enabling greater sustainability in trawling. Fishers are quick to invest in and adopt new technology and precision fishing technology in voluntary use by commercial fishers is shrinking the trawling footprint further.

Smaller fleets of vessels are catching the same amount of fish on shorter trips. Nets have bigger mesh to let smaller fish out and weigh a lot less, so they run more lightly along the seafloor. And sensors on the nets tell a skipper when a net is full so they can bring it up sooner.