Seafood NZ Latest Feature
Spotlight on hoki
It's been a big year for hoki-watchers. The commercial catch limit was increased, industry made an application for renewal of Marine Stewardship Council certification and, of course, there was another major stock assessment. We take a look at the way hoki is managed and reviews the year in hoki.
New Zealand hoki can't seem to stay out of the news. In a sense that stands to reason - it is New Zealand's second highest earning finfish, bringing in $172 million in export earnings in the 2010 calendar year. Its moist, white and flaky flesh make it perfect for turning into fish block ensuring it turns up in supermarkets and restaurants around the world. Famously, it also plays the starring role in McDonald's fish burger.
Perhaps because of its profile, some of the attention it has attracted has not always been complimentary. Claims have been made by some New Zealand environmental groups that the stocks are not sustainably managed and that hoki fishing is causing declines in seabird and fur seal populations.
These claims have been repeated by some New Zealand politicians, as anyone who was at the latest New Zealand Seafood Industry Conference will attest. Green MP, Gareth Hughes, made allegations to the effect that the hoki fishery is unsustainable to the shock of the audience of fishers, quota owners, scientists government officials and fisheries managers.
But there's another story about hoki that has been emerging over time, backed up by some of the highest quality fisheries science and fisheries management practises in the world. This story may be less generally known than the occasional allegations of doom, but to the fishers, quota owners, scientists and Ministry officials who are directly involved in the business of managing the fishery, it's much more convincing.
Hoki, the basics
The government sets a single catch limit for hoki by regulation, but it's wrong to think about New Zealand's hoki population as a sort of single nation of fish going about its life in a neatly bordered area of New Zealand's exclusive economic zone.
Hoki live in a lot of different areas within New Zealand's exclusive economic zone, and the varied natural conditions of its habitats play a critical role in its numbers. It is fished by mid-water trawling at depths of around 300 to 600 metres during the winter spawning season, and is bottom trawled at other times of the year.
There are four main fishing grounds for hoki and two separate stocks. To ensure sustainable management, each stock is separately monitored and assessed and the Minister in charge of fisheries tasks industry to manage their catches within separate catch limits set for each of the Western and Eastern Stocks.
The four main fishing grounds are: along the north-west coast of the South Island, and in the Sub-Antarctic region (making up the western stock); and in Cook Strait and along the Chatham Rise (making up the Eastern Stock).
These distinctions are important because the two stocks behave in different ways, but more about that later.
"But out of this situation, fisheries scientists, fisheries managers, industry and government have built a system which is both predictive and reactive."
Managing the hoki stocks
Hoki processing line.
Imagine a control room with a lever for each factor that affects the hoki fish stock. Above each lever is a label saying things like ‘availability of plankton', ‘climate', ‘ocean currents', ‘fishing pressure' ‘ocean temperature', and so on. This room is a fisheries manager's dream. From the comfort of his swivel chair he is able to control each lever to ensure the stock stays in a predictably strong condition. Accountants would also be quite fond of this room because it would enable businesses to conduct detailed and reliable forward planning of their fishing effort.
Of course this kind of control in a wild fishery is impossible. In a natural system some things will happen for reasons we can't quite understand, let alone pull a lever to control. In practice, the only lever fisheries managers have a firm grip on is the one marked ‘fishing pressure'.
But out of this situation, fisheries scientists, fisheries managers, industry and government have built a system which is both predictive and reactive. In other words, it allows hoki fisheries managers to both plan for the future and react to change.
The foundation for this management system is robust estimations about how many hoki are in the water calculated through trawl surveys, catch sampling and stock assessment modelling.
On the predictive side, fisheries scientists can take all of this information as a starting point and, by accounting for known factors like fish mortality rates, they are able to make predictions about what the fishery will look like over time. This point of this process, called projection, is to get to a point where scientists can say ‘if you take this amount of fish out of the water, this is the range of things likely to happen.' From there, fisheries managers can apply agreed strategies about how they will manage the fishery if certain conditions are met.
But managers don't rely on these projections alone because they can't account for all the factors that affect the stocks. In particular, there are a lot of natural factors which may affect the numbers of new fish coming into hoki stocks - a process called recruitment. A period with good conditions for recruitment, like lots of plankton available for hoki larvae to eat, can translate to abundant hoki stocks in the future. Of course, the reverse may also occur. These natural fluctuations are difficult to predict. Variations in recruitment levels as high as 18-fold have been recorded between successive years. Scientists and mangers factor these variations into their estimations and predictions.
The Western Stock of hoki has recently provided a good illustration of these dynamics in practice. The years between 1991 and 1994 provided for stronger-than-average recruitment into the Western Stock, leading to annual hoki catches of between 100,000 and 140,000 tonnes during the period 1997 and 2002. But, during 1995 to 2001, recruitment into the Western Stock was much lower. Thanks to the high level of detailed information from monitoring and from the stock assessments, fisheries managers were able to spot this trend and to make stepped reductions to the catches from the Western Stock, reducing catches down to 29,000 tonnes by 2007.
These large catch reductions were economically challenging to industry, but quota owners understood that they were necessary to protect the fishery and made the necessary reductions in fleet size and in processing capacities. It worked, and the science indicates the Western Stock has now rebuilt to within the management target range enabling the Minister of Fisheries to announce a staged increase in the Western Stock catch limit in each of the past three years to progressively raise it back up to 70,000 tonnes for 2011-12.
Getting together on the details
Since the Ministry and industry essentially want the same thing - productive and sustainable hoki fisheries - both agreed it made a lot of sense to work together and gain efficiencies where they could.
In 2006, the Deepwater Group Ltd and the Ministry signed a partnership agreement which identified ways to do this. This has proven so productive that it was updated in 2008 and in 2010.
Deepwater Group Chief Executive Officer George Clement said:
"Quota owners are committed to ensuring New Zealand's deepwater fisheries are recognised as being the best sustainably managed fisheries in the world. The Ministry is tasked with ensuring New Zealand's fisheries are managed to provide for sustainable utilisation. To us it was a no-brainer to form a constructive working relationship with the Ministry - one in which we share agreed strategic outcomes and can combine our operational capabilities to achieve our goals."
While this is somewhat unique, it is also a very efficient and effective way to manage fisheries - combining the best knowledge and know-how of industry and government. Concern has been expressed about this partnership by some environmental groups who feel ‘left out,' says Mr Clement.
"We would welcome their constructive engagement and invite them to step up, participate, and contribute to ensure New Zealand achieves these sustainability outcomes."
Recognising that the lifeblood of any fisheries management is information, in 2009 the deepwater industry proposed a ten-year science and information plan that would increase the annual investment in monitoring and research by 150 per cent and set in place agreed monitoring and science programme for at least a decade. The Ministry supported this approach and, in 2010, implemented the programme.
Both the Ministry and industry are committed to use the most efficient and best available methods, including specially developed technology to allow real-time reporting of commercial catching operations back to the Ministry. Never before has this level of detail and timeliness been available to fisheries managers.
Guided by numbers
Processing hoki.
One of the concepts scientists use to benchmark the performance of a fishery is B0. This is an estimation of the size of a fish stock in the absence of fishing, essentially providing a theoretical baseline. Industry and government have set the management target for both hoki stocks at 35 per cent to 50 per cent of B0 - a level that optimises both biological and economic outcomes over the long term.
To put this target in context, the maximum sustainable yield (MSY), which is a measure of the fishery at maximum biological production, is estimated to be 23 per cent to 24 per cent of B0. Fisheries managers and quota owners decided to follow a principle of caution by setting a higher management target stock size.
"To help them reach and maintain the target, quota owners and managers contracted scientists to model hoki stocks under different assumptions of catch levels, recruitment levels, fish size, catch rates and performance of each of the four fisheries. This process is known as a Management Strategy Evaluation and enables fisheries managers and quota owners to systematically look at the various trade-off between catch levels, catch rates and stock size to ensure we optimise both the conservation and the utilisation of our hoki fisheries," says Mr Clement.
Fisheries scientists examined the available information and concluded that in order to stay within the target range, the hoki fishery should catch between 15 per cent to 20 per cent (between one in five and one in six) of the available hoki.
Judicious control of the lever marked ‘fishing pressure' allowed the Western Stock to rebuild after a period of poor recruitment led to it falling below target levels. It has now more than doubled in size from an historical low of 17 per cent of B0 in 2006. The Eastern Stock size has been maintained within the target range and is currently slightly above this.
Latest adjustments to the commercial catch allowance
The New Zealand hoki fishery is looking to renew its MSC certification.
In October, then Fisheries Minister, Phil Heatley, increased the total allowable commercial catch for hoki by 10,000 tonnes to 130,000 tonnes.
The Minister said the increase reflected continuous improvement in stock status.
"This is another positive example of good fisheries management in practice, where we were prepared to make the tough calls in terms of reductions to catch limits but are now reaping the benefits.
"The science also indicates that the hoki fishery could support an even greater catch increase, but it is important that we act responsibly so I have agreed to a more modest increase."
Both stocks of hoki were to undergo a trawl survey this year and the results will inform a further stock assessment next year, he said.
While most hoki quota owners agreed with the change, it was not universally welcomed within the industry. Eric Barratt, Managing Director of Sanford Ltd favoured an even more precautionary approach and preferred to wait for next year's stock assessment before making any further increases to the Western Stock catch limit.
"These large catch reductions were economically challenging to industry, but quota owners understood that they were necessary to protect the fishery and made the necessary reductions in fleet size and in processing capacities."
Limiting the effects of the hoki
Every form of food production, from organic vege-patches to factory-scale dairy production, is going to have some effect on the environment. The hoki fishery is no exception. Even though every care is taken to ensure that there are enough hoki left in the water to keep the stocks healthy and thriving, fishing has some side effects that need to be carefully monitored and managed.
Fortunately for the fishery, and those whose livelihoods depend on it, fisheries managers have put in places measures to make sure all of these effects are wellmanaged and are not posing unsustainable outcomes.
Bycatch
The hoki fishery is responsible for very little bycatch and most by catch species are separately managed under the Quota Management System.
This has been backed up over time with data showing that more than 85 per cent of the catch in the hoki target trawl fishery is hoki. Of the remaining 15 per cent, 10 per cent is accounted for under the Quota Management System.
Interactions between seabirds and hoki trawlers is a potentially challenging area for fisheries managers as seabirds look to fishing vessels as an opportunistic source of food and can be very determined and clever about how to get at it, often putting themselves in harm's way when doing so.
Accidental interactions with seabirds have been significantly reduced through a range of improved seabird mitigation measures. Since 2006, all trawlers over 28 metres in the hoki fishery have been required by law to use warp mitigation devices which act as visual barriers to deter seabirds for entering the ‘at risk' area ahead of the trawl wires. In addition the Ministry and Deepwater Group also require all trawlers fishing hoki to conform to Vessel Management Plans which require careful procedures for discarding their offal to reduce the chances of attracting seabirds to areas of high risk.
New Zealand fur seals are also attracted to hoki trawlers at times, seeing an opportunity for an easy meal. All hoki fishing vessels also use special handling procedures to minimise the chances that fur seals will be caught and to enable any that are caught to be released alive and unharmed.
Bottom trawling
Bottom trawling is the main method of fishing for hoki outside of the winter spawning season, particularly on the Chatham Rise and in the Sub-Antarctic fisheries.
Environmental groups have expressed their concerns about the effects of bottom trawling on life on the ocean floor. The truth is that the effects of bottom trawling on soft sediment habitats, where much of hoki bottom trawling is done, are not well researched and getting definitive answers is both challenging and expensive.
Recent research from Canada suggests that impacts from fishing on similar seabed habitats are not long standing and will likely repair in short to medium timeframes. Taking into account that some changes to seabed habitats are an inevitable consequence of fishing; that the New Zealand economy depends upon sustainable food production, and that more than 90 per cent of the seabed within the New Zealand Exclusive Economic Zone has never been contacted by trawling, the Deepwater Group and the Ministry have decided to adopt a spatial management approach. In practice this means closing off large, unfished environmentally representative areas of the seafloor to trawling.
As a result, more than 30 per cent of the New Zealand's Exclusive Economic Zone, the fourth largest in the world, has been closed by law to bottom trawling. Within this, 6.2 per cent of the hoki habitat range is closed.
An independent analysis showed that trawls targeting hoki in 2008-09 touched the ocean floor in only 1.5 per cent of the hoki habitat range. This reinforced the view of industry that fishing occurs in the same locations every year. These areas have remained productive, and together they comprise only very small areas when compared to the large area that hoki live.
Certification
For more than a decade, New Zealand's hoki fisheries have met the high environmental standards required by the Marine Stewardship Council's (MSC) certification scheme. The hoki fisheries were first certified to the MSC's rigorous environmental standards in March 2001. They were subsequently re-assessed and re-certified again in 2006, and are now undergoing a third in-depth assessment before the current five-year certificate expires in November 2012.
"New Zealand's hoki fisheries are widely is recognised as being amongst the best sustainably managed trawl fisheries in the world. Independent verification of this through the MSC programme is an integral part of our quality verification. New Zealand hoki was the third fishery ever to gain MSC certification back in 2001, and this has allowed us to benchmark our improvements and to remain confident that our management practices continue to be world-leading," says Mr Clement.
The MSC uses independent certification bodies to undertake the assessments and audits. The Deepwater Group has contracted one of these, Intertek Moody Marine Limited, to examine the hoki fisheries in three key areas: the levels of the target fish stock, the environmental impact of its fishing operations, and the management and governance systems that are in place.
Patrick Caleo, MSC Manager Australia New Zealand, says that the news that the New Zealand hoki fishery is seeking re-assessment shows the MSC programme is delivering solid benefits to the fishery and their decision to seek recertification is a great vote of confidence in what the MSC aims to achieve.
"Thanks largely to the effective management of the fishery by the New Zealand Ministry of Fisheries and the New Zealand fishing industry itself, this fishery has clearly demonstrated significant levels of stock recovery in recent years. Its stocks are now seen as being above the required levels for the fishery to be sustainable into the future, which is a great result.
"In addition, since its original certification the fishery has actively sought out and applied methods and strategies to reduce by-catch; minimise its impact on seabirds and fur seals and has established benthic protection areas to protect a broad range of seabed habitats and ecosystems."
Last word
Sound fisheries management practice will always be a work in progress, says Mr Clement.
"New Zealand hoki has proven to be amongst the best managed fisheries in the world, being MSC-certified for the past decade. We are confident that our performance will meet and exceed the high standards for a third period. We remain committed to our programme of continuous improvements and to ensure we continue to tread lightly in our oceans to provide this valuable food source."