• April 27, 2017
The Department of Conservation is currently working on a plan to guide the research and protection of New Zealand sea lions. Photo: Wikimedia Commons / Karora
Forest and Bird has called for a ban on trawling on the area surrounding a southern marine sanctuary.
The group has called into question the effectiveness of sea lion exclusion devices in the Auckland Islands Marine Mammal Sanctuary. It wants the ban imposed until more is known about the devices, known as SLEDs.
The devices are secured to the back of squid trawling nets with the aim of preventing sea lions from getting caught.
However, there is little scientific evidence to prove they work, and a sea lion was recently found dead after it had become trapped.
Marine conservation advocate for Forest and Bird, Katrina Goddard described the threat of trawling on the flippered mammals.
“New Zealand sea lions are nationally listed as critical and that’s one of the highest threat classifications the Department of Conservation gives out,” said Mrs Goddard.
“We know this fishery is killing the world’s most endangered sea lion and that the devices they use in the nets are surrounded by uncertainty.”
The New Zealand sea lion population is currently at 10,000, but this number is in decline, according to the Department of Conservation.
Auckland Island Marine Reserve is the main breeding ground for the New Zealand sea lion, and the animals will often hunt in the surrounding area, according to Mrs Goddard.
Associate professor of zoology at Otago University, Dr Bruce Robertson, echoed Mrs Goddard’s concerns.
“We don’t have any information on how sea lions are interacting with the SLEDS, and that is largely because it has been quite difficult to get that information,” he said.
This was due to the irregular rate of interaction between sea lions and SLEDS, Dr Robertson said.
A possible solution would be to swap trawling for the squid fishing method of jigging.
“Jigging is done with a different kind of boat that essentially has lots of lights on it and goes out at night,” said Dr Robertson.
“Squid are attracted to the light and then the boat drops down hundreds of barbless hooks that the squid latch onto.”
Dr Robertson believed this style of fishing is far more environmentally sustainable and would result in a better catch.
“When you trawl, you basically drag a net around for about eight hours, and so the catch gets squished,” he said.
“Whereas with jigging, you catch the squid and pull it up onto the deck straight away for processing.”
The Department of Conservation and Ministry of Primary Industries have the authority to place the ban and were contacted for comment but did not respond by deadline.