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We will look at both inshore and deep-sea bottom trawling, because they differ. 


There are hundreds of trawlers churning up the seabed off our coasts  

We actually have half the number of trawlers operating in our inshore waters compared to 2008. There are now 103 trawlers (under 32m) compared with  more than 200 in 2008. 

They are churning up all of our coastal seabed. I can see them from my bach 

Only 17 percent of our territorial (inshore) waters are trawled, and most of this  takes place on loose sediment areas of gravel, sand and mud. 

The inshore trawl footprint is reducing. Last year the footprint was 83 percent of what it was in 2009, and where fishers trawl varies a little each year. In any year, nearly 99 percent of the area trawled will have been trawled before, with around 60 percent of that trawled every year. We don’t trawl new ground because we neither have to, nor want to. 

They are depleting our coastal waters of fish by trawling it all up in big nets 

Inshore trawl vessels are small. The average size is 16m, but ranges from 10m to 30m, and the average bag they catch each tow is less than 500 kg.  

There is no need to trawl for our fish, you can catch it by other methods 

It is true that some of the species, like shark and flounder, could be caught by set netting, but the opportunities are more limited with 31,500 km2 of our inshore waters now closed to set netting.   

What about catching fish on a line? 

Catching costs for longline fishing are some 2-3 times the cost of trawling—and that cost will be reflected in what you pay for your fish. 

You are operating in the past. Trawling is a fishing method that is outdated 

You’d be surprised at how trawling has changed over the years: 

  • the net mesh has become larger, often now 150 mm, to let small and juvenile fish escape the net. 

  • more nets are cut differently to ensure the mesh stays open to permit small fish and unwanted species to exit the net. 

  • there is a greater use of nylon fibre in warps rather than the more traditional wire – this allows seabirds to see the net and not be captured on the warp.  

  • modern inshore trawl rigs are lighter all round, lightening the impact on the seabed and lowering the fuel used to tow the nets. 

  • a number of fishers have moved to use Precision Harvesting Nets which allow the fish to swim inside the net until it is hauled on board the vessel. 

  • trawls are shorter to keep the fish in better condition for the consumer. 

Isn’t trawling a big contributor to climate change because carbon is released when the seafloor is disturbed? 

Any carbon caught in the seabed is largely released the first time it’s trawled. Once it’s released, trawling in the same area doesn’t release any new carbon—it all went in the early years of trawling. The seabed can only accumulate marginal new carbon between trawls. It’s one more myth that is misleading. 


Huge boats are vacuuming up everything in their path 

Well, we have way fewer trawlers these days. In fact, there are 47 percent fewer trawlers larger than 28 metres than there were in 2005. Interestingly though, we are harvesting the same volume of fish (around 350,000 tonnes) and that is because we have scientifically improved our fishing methods and, at the same time, reduced our environmental impact. 

The vessel numbers may be down, but they still hoover up the seafloor 

The area fished annually by deepwater trawlers has been reduced by 46 percent since the peak in 2002. Each year, deepwater trawlers contact only 1.1 percent of the seabed in our large EEZ and, since records began, only 8 percent of the seabed in the EEZ has ever been touched by trawling. 

How is the industry reducing its environmental impact? 

Compared to 2005, the number of albatrosses captured is down 74 percent, fur seals are down 90 percent, sea lion captures are down 80 percent, and common dolphins are down 99 percent. That means we have gone from the capture of 1186 albatrosses to 307 birds. In 2005, we captured more than 1000 fur seals and that number is now down to around 100 and decreasing. Sea lion captures are down from 45 to nine on an annual basis and common dolphin captures have reduced from 85 to close to zero. 

That’s still too many 

We agree and expect those numbers to decrease as we continue to find better ways to mitigate our encounters with seabirds and marine mammals. 

Weren’t you lot responsible for wiping out orange roughy?  

In the 1980s, when we first started fishing orange roughy, the management was not as responsive to the needs of the fishery as it is now. No one back then knew how productive orange roughy were, how long they lived for,  nor did they have any clue about how many there were.  

However, now we know a lot more about our orange roughy fisheries and our management of them is robust. In 1986 with the introduction of the Quota Management System (QMS), managers relied on best available science and technical information for the management of our fish stocks. This information included research into the distribution, abundance and productivity of our orange roughy fisheries and their maximum sustainable yields. The QMS provides for only a small number of fish in each stock to be caught to ensure there are enough left in the population to keep the numbers at a sustainable level.  

The really good news is that the abundance of our orange roughy stocks has improved markedly, with three of our orange roughy fisheries certified sustainable against the Marine Stewardship Council’s fisheries standard—putting these fisheries in the top 5 percent  of the best managed fisheries in the world.  

No one can see what really happens at sea and you and you pretty much can do what you like 

Every vessel is under constant monitoring and must electronically report every fish it catches, every fish that is returned to the sea, and every interaction with a seabird or other protected species. Furthermore, all deepwater vessels have government observers on board, with coverage averaging a little over 30 percent overall, however in some fisheries, observers can be aboard up to 85 percent of all fishing vessels. 

Bottom trawling is totally indiscriminate, hauling up everything 

In New Zealand fishing is subject to the QMS. For every fish that is taken, the fisher has to have quota for it—if they do not, then they must pay a government-imposed deemed value until they can procure some quota.  

Fishing is very selective, with fishers only targeting want they have quota for and want to catch, and no more. Fishers are not interested in catching unmarketable species, or other bycatch, and do all they can to improve their selectivity. To this end, technological innovation plays a big part in making catches more selective. Innovations such as the Acoustic Optical System (AOS) provides skippers with acoustic data and video images of target stocks which assists in their management. 

But sometimes you catch protected corals? 

Yes, sometimes that is inevitable. While we fish in the locations where the fish are, sometimes fishing gear can incidentally encounter corals. Just under 5 percent of all deepwater tows encounter corals. Catches of coral vary, but on average coral catches per tow are less than 1 kg, and much of that is usually dead coral rubble. 

Corals are protected in New Zealand, and as such all coral captures are reported to the Ministry for Primary Industries.  

What about trawling seamounts?  

Deepwater Group (DWG) represents the owners of quota in New Zealand's major deepwater commercial fisheries, including those for hake, hoki, jack mackerel, ling, orange roughy, oreos, scampi, southern blue whiting, and squid. Shareholders of DWG collectively own around 91 percent of the quota for deepwater fisheries in New Zealand.  

There are 142 seamounts in our EEZ, with 127 (89 percent) of those either closed to trawling or have never been trawled. We understand there may be confusion  about this, as environmental groups claim there are over 800 seamounts in the New Zealand EEZ. These groups are counting every underwater feature that stands 100 metres, whereas the Standardised International definition of a seamount is at or above 1000 metres, with features of 100 metres defined as hills and features over 500 metres defined as knolls.