Species Focus - Hoki (Macruronus novaezelandiae)
Hoki is one of New Zealand's biggest fish exports, and forms an important part of the catch for offshore trawlers in New Zealand waters.
Hoki is caught mainly by mid-water trawl during spawning in late winter. This happens off the South Island's west coast and in Cook Strait. Outside this time, hoki are mainly caught by bottom trawl on the Chatham Rise and to a lesser extent in subantarctic waters.
Although hoki grow reasonably quickly, they do not mature and join the adult spawning population until they are four to five years old. There was a phase during the mid-late 1990s when fewer young hoki were produced. This meant a lot fewer adult fish were available over the last few years, so catch levels had to be reduced quite severely.
Status of the fish stocks
Two hoki stocks are recognised in the HOK1 management area. The sizes of these stocks are monitored using trawl and acoustic surveys. Catch/effort data and information on size and age of fish caught are also used to assess the stocks annually.
The 2005 stock assessment indicates the western fish stock is below the government's target level.
This happened because fewer young fish were coming through into the adult population. To let the stock rebuild, the government has cut catch limits, and is closely monitoring the situation.
The 2005 assessment indicates the eastern hoki stock is above the target level.
The catch limit of hoki has been progressively reduced from 250,000 tonnes in 2000/01 to 100,000 tonnes in 2005/06. Fishing at the current level appears sustainable, and the forecast is that hoki stocks overall will increase at a slow rate. How quickly they rebuild will depend on how many young fish come through into the fishery over the next few years.
Current management issues
The main issue at present is ensuring enough young fish come through into the fish stocks. Most hoki spend their early years on the Chatham Rise fishing grounds, and it is important that enough of these fish reach mature size.
The industry has introduced fishing strategies that avoid catching too many young fish.
Other concerning issues are the deaths of seabirds and seals, and the impacts of bottom trawling in the hoki fishery.
The government and industry are working on ways to keep albatrosses and petrels away from the sterns of trawlers, where their trawl warps enter the water. The government is also working on the issue of bottom trawling in this fishery.
The industry has developed, and updates, a code of practice to avoid seal captures.
Hoki catch limits and allowances
The catch limits and allowances for hoki have been set at 101,040 tonnes for the 2005/06 fishing year.
Of this, the government has allocated 100,000 tonnes to commercial fishers. This is split (by agreement between government and industry) between the two hoki stocks. The government has also allowed 40 tonnes to cover the combined recreational and customary catch, and 1000 tonnes to cover issues like illegal fishing (eg mis-reporting), and wastage or injury of fish.
The hoki fishery is managed using a range of restrictions. Some of these protect the fish stocks (eg catch limits and a voluntary code of practice to protect young fish). Others restrict large vessels from fishing close to shore, to protect the commercial viability of inshore fishers.