Seals and sea lions
The New Zealand sea lion (formerly known as Hooker's sea lion) Phocarctos hookeri, is a protected marine mammal. The New Zealand fur seal (Arctocephalus forsteri) and the New Zealand sea lion eat squid as part of their diet. These mammals are not at risk when squid is being caught by jigging methods (a hook and line technique), but in some areas, such as the Auckland Islands, it is not safe or feasible to use this method.
Seals and sea lions can drown if they get caught in trawl nets. Part of the problem is that unlike other marine creatures, who may try to escape a net, the seals see it as a quick source of food, and actively swim inside the nets.
The fishing industry is trying to reduce the problem in several ways. The first is limiting fishing activity to times when seals and sealions are less active.
The second approach is the development of a Sea Lion Exclusion Device (SLED) within the net. This normally consists of a strong grid placed at an angle across the front of the opening of the net. The grids are big enough to let squid swim through but are too small for larger creatures, such as dolphins, seals, sealions, or turtles to get through. They are guided up the grid, by the motion of the water, and can then escape by swimming through an opening in the top of the net.
Credit: Penny Heath, Deepwater Group Ltd
In 1986 a 12 mile nautical mile 'no fish' zone around the Auckland Islands was established under the Fisheries Act to protect the sea lion. In 2003 the unique nature of the marine ecosystems around the Auckland Islands and the need to continue a ‘no fish' zone led to the establishment of the Auckland Islands Marine Reserve.
An annual by-catch limit or MALFIRM (Maximum Allowable Fishing Related Mortality) for the New Zealand sea lion is set by the Minister of Fisheries. All fishing vessels with squid quota for the Auckland Island area maintain a voluntary code of practice designed to reduce the accidental by-catch of fur seals and sea lions.
More information is available on the Deepwater Group's website »