ISSUE 35 ■ MAY/JUNE 2010 $5.00

GEODUCKS HAVE AQUACULTURE POTENTIAL

CO2 – A CHALLENGE FOR RECIRCULATING SALTWATER

TRIPLOIDS INCREASE OYSTER PRODUCTION

FOR MAORI AQUACULTURE

SETTLEMENT REACHED

2 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

An informative journal for the aquaculture industry

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General: Reproduction of articles and materials published in New Zealand Aquaculture in whole or part, is permitted provided the source and author(s) are acknowledged. However, all photographic material is copyright and written permission to reproduce in any shape or form is required. Contributions of a nature relevant to the aquaculture industry are welcomed and industry participants are especially encouraged to contribute. Articles and information printed in New Zealand Aquaculture do not necessarily reflect the opinions or formal position or the publishers unless otherwise indicated. All material published in New Zealand Aquaculture is done so with all due care as regards to accuracy and factual content, however, the publishers cannot accept responsibility for any errors and omissions which may occur. New Zealand Aquaculture is produced bi-monthly.

3 EDITORIAL

4 NEWS A look at what’s happening in the industry

6 CO2: a challenge for saltwater recirculating aquaculture systems Measuring the effect of elevated CO2 levels on young Atlantic cod

8 ACROSS THE DITCH: Aquaculture losses hint at wider health issues Two aquaculture areas are being hammered by agriculture pursuits

10 OCEAN LAW: Settlement marks a significant step Everyone gains with passage of innovative new legislation

11 ECONOMICS OF AQUACULTURE: Geoducks in ponds Software assesses financial feasibility of potential ventures

12 MAHANGA BAY MARKS 35 YEARS OF RESEARCH Wellington Harbour is ideal for aquaculture research

14 INCREASING PRODUCTION EFFICIENCY THROUGH TRIPLOIDY Triploid Pacific oyster spat grow fatter and faster than diploids

15 MARINE FARMS BATTLE ON Industry waits for reforms with baited breath

CONTENTS

EDITOR:

Keith Ingram

ASSISTANT EDITOR:

Mark Barratt-Boyes

MANAGER:

Vivienne Ingram

ADVERTISING:

Hamish Stewart

DESIGNER: Rachel Walker

CONTRIBUTORS:

Sam Gale, Serena Adams, Bob Hickman, Helen Mussely, Achim Janke, Damian Morgan, Hayley Campbell, John Mosig

PRINTER: GEON

DISTRIBUTION: By subscriptionand insertion with Professional Skipper

ISSN 1176-5402 ISSN 1176-8657 (web)

ISSUE 35 MAY/JUNE 2010 $5.00

GEODUCKS HAVE AQUACULTURE POTENTIAL

CO2 – A CHALLENGE FOR RECIRCULATING SALTWATER

TRIPLOIDS INCREASE OYSTER PRODUCTION

FOR MAORIFOR MAORIAQUACULTURE

SETTLEMENT REACHED

ON THE COVER:Mahanga Bay Aquaculture

Centre

PHOTO BY:Bob Hickman

TM

6 9 12

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 3

EDITORIAL

In March this year the attorney-general, Hon Christopher Finlayson, released the National government’s review docu-ment of the Foreshore and Seabed Act 2004 for consultation.

National’s proposal goes a lot further than Labour’s act did and will result in more tribes gaining a great deal more power, such as veto rights over developments in their patch, around our coast.

It effectively sets out plans for a large degree of co-management of parts of New Zealand. The foreshore and seabed has been described as those waters from mean high-water springs out to the 12-mile limit, and includes the air above and land below.

Under the government’s proposals, the 2004 Foreshore and Seabed Act would be repealed and a new law passed which would take away full Crown ownership and vest the foreshore and seabed as “public domain” instead. Nobody would have ownership. This is interesting. The devil will remain in the detail, as this will take some working through.

The new law would also enshrine the rights of public access and navigation, except where it would be unreasonable, for instance public safety on wharves, port areas or developments. But the security of the use of safe havens as of right remains unclear.

However, it ensures the existing rights of private owners are not affected until, that is, when current leases, licences or occupation rights expire. What will happen then and who gets to have the last say also remains unclear.

This document is clearly designed to meet the government’s commitment to the Maori Party. In doing so it may open a festering sore again, although the government has stated that retaining the status quo or a modifi cation of it is one option.

The government also proposes weakening the current test that applies for proving territorial rights – a step which will mean more hapu can qualify. It removes the need for hapu to have had unbroken title to adjacent land since 1840.

Instead, hapu will have to show only exclusive use of the area over other hapu. Each hapu would have to meet a series of tests before customary title was awarded. Those who did not reach it could still have other, lesser rights recognised.

The document remains silent on the rights of tauiwi or Europeans, who may be able to prove and exercise the same occupation use as Maori.

The most important change between National and Labour’s laws is that Labour set the test for the award of customary title extremely high and National has lowered it.

National has ditched any preference for simply restoring the right of iwi to explore customary title at the High Court under the common law – guided only by other court judgements. Instead, it has gone down exactly the same path as Labour in proposing in statute two sets of rights: territorial rights “otherwise known as customary title” and non-territorial, and the tests that must be met before they can be awarded.

Unfortunately, the “awards” are not clearly spelled out, nor is any effect on non-Maori discussed. Under National’s proposal, iwi gain a lot of legal rights they don’t have already. One of them would be the right of veto over consents for coastal permits given by either the regional council, or even Ministers of the Crown.

In practical terms, if hypothetically the law had been in place 10 years ago and the local Whangamata iwi Ngati Hako had convinced the government it had customary title over that area, it could have killed the marina project at birth. It would never have got off the ground.

The document says, “There would be no obligation on a coastal/hapu to comply with the requirements of the Resource Management Act when giving or declining permission for a coastal permit”.

In speaking with some Maori, they also clearly share concerns. What happens to the existing agreements with Ngati Porou and Te Whanau Apanui on the East Coast? These iwi might not be over the moon about the prospect of seeing their negotiated deals unraveled.

The issues surrounding liability are not addressed. Customary awards or title still confers rights or ownership, so confusion will remain.

How this will affect the aquaculture industry remains a burning question. Clearly, the desire by some seafood industry corporate companies to have defi ned ownership of water space in perpetuity will not be a happening thing, and rightly so.

How the access and utilisation rights for aquaculture management areas are defi ned and the security of leases to build investment and businesses on will remain the burning question for the government.

Foreshore and seabed – are we opening another can of worms?BY KEITH INGRAM

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NEWS

4 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

TASMANIA KEEPS PACE WITH CHANGEThe impact of climate change and advances in open ocean aquaculture are likely to be hot topics of debate at the 2010 Australasian Aquaculture International Conference and Trade Show.

The conference will be held in Hobart, Tasmania, at the Hotel Grand Chancellor from May 23 to 26. It is expected to be the leading aquaculture event in the Asia-Pacifi c region this year.

The aquaculture industry in Tasmania is well known for producing high-quality seafood, including Atlantic salmon, sea-raised trout, Pacifi c oysters, blue mussels and abalone.

The Tasmanian salmon industry is a new success story for aquaculture in Australia following a self-rescue process during recent years, so the industry is now experiencing strong growth and positive projections.

The island’s oyster industry is also developing and currently employs over 300 people. They produce around 3.6 million dozen Pacifi c oysters a year with an estimated farm gate value of A$20 million.

The conference will focus on keeping pace with change, whether that is economical, technological or environmental, says the conference chairman, Roy Palmer.

“In order for the aquaculture industry to continue to evolve, there has to be adequate emphasis given to the role that change plays in our lives,” Palmer said.

The conference will address the 21st century challenge of unrivalled environmental concerns and performance, getting the right skills to the right place, industry economics and the requirement for technological adaption.

The trade show is expected to be one of the highlights of the conference. “Showcasing the latest products and services available to

the aquaculture industry, the trade show will expose delegates to cutting-edge expertise and innovations from around the world,” he said. Registrations are expected from over 40 countries. Sessions will include feed for the future, certifi cation and eco-labelling, effi cient aquaculture production and reducing red tape in aquaculture regulations.

Day one offers sessions with a focus on keeping pace with changes in trade and markets. The plenary session will be presented by Mark Ryan from Tassal, who will look at perspectives on the Australian trade of seafood, as well as aquaculture’s place in the seafood supply chain. He will also present Tassal’s strategy for keeping pace with predicted changes.

Day two’s focus is on keeping pace with long and short-term changes. This will see Dr Alistair Hobday, a senior research scientist at CSIRO Marine and Atmospheric Research, present a highly anticipated plenary session on climate change.

Dr Hobday’s research spans a range of topics, including spatial management, migration of large pelagic species, environmental infl uences on marine species and the impact of climate change on marine species.

He will provide the latest information on climate change and what the aquaculture industry needs to know in order to ensure it is ready for the opportunities and challenges this issue presents.

The second plenary speaker for day two is Adolfo Alvial, whose presentation will cover sudden change with long-term consequences. As part of this, Alvial will provide an overview of the Chilean salmon industry’s ISA outbreak and the enormous fi nancial, social and political changes that have occurred since.

On day three, the focus of the plenary sessions move to keeping pace with changes

affecting the global aquaculture industry. Peter Redmond from the Global Aquaculture Alliance will speak about the integrity of the global aquaculture industry through internationally agreed standards. He will also touch on what the alliance is doing to help the industry cope with change.

Other sessions during the conference explore topics such as open ocean aquaculture, touted as the next frontier, genetics and genomics, lean manufacturing in aquaculture and South East Asia aquaculture trends. National and international speakers will provide narratives on these and many other topics at both a practical and scientifi c level.

The open ocean session will provide an opportunity to look at the most recent technology developments, the challenges facing the sector, technical and regulatory issues and operational experiences. It will conclude with possible development trends for technology and species. Not yet established in Australia, open ocean aquaculture is now operational in Norway, Chile, China, Ireland, Panama, Italy and Spain, and offers considerable opportunities for expanding Australia’s fi n fi sh sector.

The conference is supported by the Australian Seafood CRC, the Fisheries Research and Development Corporation and the Australian Government Department of Agriculture, Fisheries and Forestry.

For more information, contact the conference organiser, Sarah-Jane Day, on 0437 152 234 or email sarah-jane.day@aquaculture.org.au.

See www.australian-aquacultureportal.com and www.discovertasmania.com

OFFSHORE MARICULTURE CONFERENCEThe programme for the Offshore Mariculture Conference 2010 is aimed at farming companies, research organisations and suppliers looking to update themselves on the latest policies, products, research and case studies within the fi n fi sh, shellfi sh and seaweed offshore farming industries.

The two-day technical conference will be held on June 16 and 17 at the Hilton Imperial Hotel, Dubrovnik, Croatia, and will be followed by a visit to a sea bass and sea bream fi sh farm on June 18.

Papers on practical offshore farming operations, including feeding, preventing escapes and health issues, as well as updates on manufacturers’ latest products, spatial planning and monitoring and future technologies will be included, says the chair, Arne Fredheim of CREATE/Sinter.

There will be case studies from international fi sh farmers and from the Croatian fi sh farming companies Kali Tuna, Atlantis Group and Riba Mljet.

Dr Mark Soboil of Aotearoa Fisheries will present a paper on the implications of individual transferable quotas on the

BANK APPOINTS NEW AGRIBUSINESS ANALYSTThe rural bank Rabobank Australia & New Zealand has appointed Marc Soccio as a senior analyst in its food and agribusiness research and advisory division.

Soccio has taken on responsibility for covering the food retail and processing, wine and horticulture sectors for the bank’s research division.

Soccio spent fi ve years as an agribusiness investment analyst and advisor, where he developed a strong understanding of a range of agricultural markets, value chains and the fi nancial and operating requirements of agricultural businesses. He has also worked in wine operations.

Soccio holds an honours degree in commerce from the University of Melbourne, a graduate diploma in oenology (wine-making) from the University of Adelaide and is currently completing a Masters of Business Administration at the Melbourne Business School.

Marc Soccio

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 5

creation of new sea space for farms within New Zealand legislation. This paper will include a discussion on the resolution of potential coastal space confl icts using market forces.

The conference is supported by the European Aquaculture Society, the European Aquaculture Technology and Innovation Platform, the Federation of European Aquaculture Producers, the Global Aquaculture Alliance, Dansk Akvakultur and HGK, Grupacija aviculture and the aquaculture affi liation of the Croatian Chamber of Economy (and member of FLAP).

The specifi c focus on Croatia will enable government offi cials from farming nations to learn how they can adapt Croatia’s successful spatial planning policy into their own ministries of fi sheries, environment and tourism. International farming companies and suppliers looking to enter or invest in the Croatian market will also attend.

See www.offshoremariculture.com

INSTITUTE SUPPORTS CHANGES TO GOVERNMENT FUNDINGOne of New Zealand’s independent research organisations says it is cautiously welcoming a report recommending changes to the way Crown Research Institutes are funded.

CRIs currently have to compete for much of their funding, which the report by the Crown Research Institute Taskforce says creates too much uncertainty and makes them vulnerable as businesses.

The Cawthron Institute knows that only too well, says the chief executive, Gillian Wratt. It has to fi ght for every dollar to fund its aquaculture and environmental research, she says.

“Issues around security of funding and resourcing funding bids to maintain long-term capabilities are not unique to CRIs.”

The institute did not want to see any changes that would place research institutes not owned by the government at a disadvantage.

“It appears obvious that increasing overall

funding to the CRIs in the long-term risks reducing the pot the rest of us currently have access to.”

CONGRESS DISCUSSES AQUATIC HEALTH MANAGEMENTThe second International Congress and Exhibition on Aquatic Animal Health Management and Diseases is to take place on October 26 and 27 at Tehran, Iran.

The congress is being organised by the Veterinary Council of Iran. The Iran Veterinary Organisation, the Faculty of Veterinary Medicine of the University of Tehran, the Iranian Fisheries Research Organisation and the Iran Fisheries Organisation are all supporting the congress.

Topics to be discussed include• diseases, prevention and treatment • nutritional health management• water quality management, and• health management in farms.

During the fi rst congress, held in January 2009, more than 600 papers from Belgium, France, India, the United Kingdom, Germany, Malaysia, Philippines, Greece, Poland and Iran were submitted. Thirty-two Iranian and foreign companies participated in the specialised exhibition held in conjunction with the congress.

The organisers invite abstracts to be submitted and ask for word of the congress to be forwarded to colleagues who may also be interested in submitting an abstract. The deadline for abstract submissions is June 20.

See www.icahmd.com or contact the secretariat: Dr Siamak Goharkhay, Congress and Exhibition Executive Secretary, Unit 5, No. 208 Shohadaye Jandarmery St, 12th Farvardin St, Enghelab Ave. PO Box 13145-198, Tehran, Iran. Email info@icahmd.com

ACT SETTLES CROWN’S OBLIGATIONSMaori are to receive $97 million with the passing of the Maori Commercial Aquaculture Claims Settlement Amendment Act.

The payment is “full and fi nal settlement” of all Crown obligations for aquaculture space approved between September 1992 and December 2004 under the previous marine farming regime. It covers almost all of New Zealand’s current aquaculture development areas.

The act clears the last hurdle in fi nalising the agreement between the Crown and the people of the South Island and Coromandel. It also allows early cash settlements to be negotiated with other iwi.

FAO SETTING UP BEST PRACTICE DATABASEThe FAO Aquaculture Service is calling for contributions to the development of a worldwide overview and databank of codes of practice, codes of conduct, best management practices and technical guidelines in aquaculture. The Food and Agriculture Organisation is part of the United Nations.

It is inviting all those interested in promoting sustainable aquaculture development, especially aquaculture producer associations and farmer organisations, to advise it of COP/BMP documents in their countries or regions. The documents can be sent in hard copy or electronic format or by informing the FAO of the relevant website, internet link or URL.

“Your collaboration and contributions to this initiative will be most appreciated and your participation will be duly recognised and acknowledged,” said Jiansan Jia, the chief of the FAO Aquaculture Service.

For more details contact Owe Barg, fi shery resources offi ce (aquaculture), FAO Fisheries and Aquaculture Department, Viale delle Terme di Caracalia, Rome 00100, Italy. Email uwe.barg@fao.org

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6 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

New Zealand companies have invested heavily in recent years in land-based saltwater

recirculating aquaculture systems (RAS) such as the Parengarenga kingfi sh farm and the OceaNZ Blue paua venture.

Building aquaculture farms on land has a number of advantages over farming in the sea (see my article in issue 21 of NZ Aquaculture for some examples), and a key element of the engineering and economics of a land-based farm is the degree of water recirculation.

The more farm water is recirculated, the greater the accumulation of metabolic waste products, such as CO2. For the past three years I have been investigating the potential problems saltwater RAS may face from accumulated dissolved CO2.

The New Zealand Foundation for Research, Science and Technology funded my research programme in Denmark, which is where many of the world’s leading RAS design companies are located. When I left New Zealand in 2007, there was some anecdotal evidence that CO2 might be more problematic in saltwater RAS compared to the more common, and better understood, freshwater RAS.

In this article I present a summary of my research into why CO2 is a challenge to developing saltwater RAS units.

One of the main problems that has dogged aquaculturists is how to measure CO2 in salt water. A common way

of measuring dissolved CO2 is to measure the pH and the pH buffering capacity of the water, and then use some chemistry knowledge to back-calculate the CO2 concentration.

There are two problems with using this method in salt water. Firstly, getting accurate pH measurements in salt water is diffi cult because most pH probes don’t work well in salt water after a short amount of immersion time, and the generic pH buffers used for calibration are designed for low-salinity solutions.

Secondly, the high pH buffering capacity of salt water means a minor error in pH measurement (eg 0.2pH) can represent a signifi cant difference in CO2 concentration. The difficulty in accurately measuring CO2 concentration

has meant it has been hard to get a handle on what concentrations may affect farm stock.

I have been working with researchers at the University of Copenhagen to assess the accuracy and utility of a (relatively) new dissolved CO2 meter made by the Danish company Bodyguard, which works by directly measuring the gas pressure of CO2 in water.

We have found this meter can accurately measure CO2 in salt water, provided some key steps are taken in the calibration procedure and deployment of the probe. We measured the precision to be 1mg/litre dissolved CO2, suffi cient for most aquaculture purposes.

CO2: a challenge for saltwater recirculating aquaculture systemsBY DR DAMIAN MORAN

Damian Moran

The set-up used to test the Bodyguard CO2 meter. Notice that my Danish collaborator, Bjørn Tirsgård, is dressed rather like a kiwi!

A significant proportion of juvenile Atlantic cod exposed to long-term elevated CO2 concentrations developed diffuse cataracts

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 7

After being confi dent that we can easily and accurately measure CO2 concentration in salt water, a two-month experiment was undertaken to measure the effect of elevated CO2 levels on the growth of juvenile Atlantic cod in a saltwater RAS.

Very little research has looked into the long-term effects (ie. more than a few days) of exposure to elevated CO2 levels for marine fi sh. Results from the Atlantic cod study indicated that compared to the low CO2 treatment (2mg/litre), the growth rate of fi sh in the medium (8mg/litre) and high treatments (18mg/litre) were reduced by an estimated 14 percent and 36 percent respectively at equivalent body weights.

The medium and high CO2 treatments were certainly in the range one might expect to fi nd in true commercial RAS (ie. <10 percent system volume exchange per day). In addition to fi nding a dose-dependent effect of CO2 on growth, the condition factor (“fatness” of fi sh) and prevalence of eye malformations was also related to the CO2 concentration the fi sh were exposed to.

Analysis of the pattern of eye malformations is still continuing with the assistance of Dr Lincoln Tubbs, a fi sh health expert at the University of Guelph, Canada. Lincoln is a fellow New Zealander with an FRST grant to study the development of fi sh viral diseases using molecular tools. Many of the Atlantic cod from the elevated CO2 treatments were found to have developed cataracts. They were not the typical nucleated cataracts associated with nutritional defi ciencies, but were diffuse cataracts commonly observed in salmon undergoing salinity stress during sea transfer. Such cataracts suggest osmotic or acidic stress caused the lens proteins to denature.

Armed with a method of reliably measuring dissolved CO2 and some idea about CO2 effect concentrations, the next step in the research plan was to investigate why saltwater RAS appear, at least anecdotally, to have higher circulating CO2 concentrations compared to similarly confi gured and stocked freshwater RAS.

In most RAS there is usually a centralised CO2 stripping unit, which can take the form of a cascade column, airlifts or sparging tank. I compared the CO2 stripping performance of a cascade column and airlift in fresh water versus saline water (NaCl as the salinity source). While there was no measurable difference between salinities in the mass of CO2 stripped from the water, there were differences in the fi nal CO2 concentration of water exiting the stripping units.

In saline water, more CO2 reforms from the large

pool of bicarbonate (HCO3-) during the chemical equilibration process that occurs in the minutes following CO2 stripping. This means the effective CO2 stripping effi ciency is lower in saline water compared to fresh water, and offers an explanation for the anecdotal observations that it is more diffi cult to maintain low CO2 levels in saltwater RAS compared to freshwater RAS.

All of the aforementioned work is currently undergoing the peer review process and will be published in scientifi c literature soon. For those who would like to be able to calculate pH and

CO2 concentrations for waters of different salinities, alkalinities and temperatures, I have set up a comprehensive carbonate chemistry calculator on my webpage.

See www.microcosmofscience.comMy main conclusion after these three years of work is that

if New Zealand continues to invest in land-based systems to on-grow saltwater species, particular attention will need to

be given to the CO2 tolerance of the stock.The aforementioned study on Atlantic

cod indicates CO2 effect thresholds may be lower than currently realised. More research is needed into species-specifi c CO2 tolerances (for both fi sh and shellfi sh), and we need to step away from thinking that saltwater RAS units are simply briny versions of freshwater systems.

New Zealand would do well to invest in more research into how RAS perform under warm (ie. above 15˚ Celsius) saltwater conditions. Land-based aquaculture of marine species is predicted to increase signifi cantly over the coming decades, and there are plenty of opportunities for innovative marine engineering companies to provide solutions to some of the challenges facing saltwater RAS.

Damian Moran is an NZFRST post-doctorate graduate working at the Technical University of Denmark.

Email contact@microcosmofscience.com.

The CO2 stripping efficiency of a cascade column and airlift was compared using fresh water and saline water

A comprehensive pH and CO2 calculator is available at www.microcosmofscience.com

WE NEED TO STEP AWAY FROM

THINKING THAT SALTWATER RAS UNITS

ARE SIMPLY BRINY VERSIONS OF

FRESHWATER SYSTEMS

AQUACULTURE LOSSES hint at wider health issuesBY JOHN MOSIG

How’s it going over there, Kiwi. Still having a bit of trouble with that new crash hot bonza legislation that was going to propel New Zild aquaculture into the

21st century, I notice.That’s right, we heard about it over this side of the Ditch.

Don’t worry, you’re not on your Pat Malone. We have the same sort of Colonel Blimp attitude over here. “You can have any sort of aquaculture you like, anywhere you like, as long as it doesn’t alter anything about the environment.” Let them eat mushrooms.

And the way we’re going over here, that time may not be too far away. We’ve got two aquacultures hammered by agriculture pursuits. One is in Tasmania, the other in “Beautiful One Day, Perfect the Next” Queensland. But it is more than an aquaculture story; it is a major public health issue. Losses in aquaculture are becoming the canary down the mine for wider and much more alarming cancer clusters.

Tasmania’s Georges Bay, located near the stunning Bay of Fires national park, is home to some of the state’s best Pacifi c oyster growing areas. Local growers found themselves losing stock, especially after heavy rainfall.

Back in 1996 they absorbed losses of 10 percent. These losses crept up steadily until they had major fl ooding in 2004 and suffered devastating losses of 90 percent among the intertidal leases. You can follow the full story on the net.

It was told in a two-part series on ABC’s Australian Story.See www.abc.net.au and look for Something In The Water.

Just for a brief fi ll-in, a local GP, Dr Alison Bleaney, marine ecologist Marcus Scammell and the marine farmers of St Georges Bay have been battling the government and the bureaucracy over the apparent toxicity of the local water.

Bleaney had noticed an alarming number of cancer patients among people aged in their 40s and 50s. They were forms of cancer you would only occasionally come across in a metropolitan practice, let alone in rural St Helens, with a district population of just over 6000. Scammell found himself called in to investigate the oyster deaths.

Their harrowing tale of indifference and ridicule is too long to tell here, but they fi nally decided to go it alone and engage in some exhaustive water tests, paid for out of their own pockets.

It turned out that, in this case, the usual suspect – agricultural chemicals – was not the culprit. It was toxins exuded or leeched from genetically “improved” plantation trees planted in the St George River catchment in huge numbers over the previous 15 years. The nearby St Marys River has a natural bush catchment that includes the offending commercialised

species and no traces of toxins were found.There’s a Kiwi connexion here, too. To verify their fi ndings

they sent samples to an independent and globally recognised toxicologist, Dr Chris Hickey of the National Institute of Water and Atmospheric Research. Chris praised the science of the process and made a valuable contribution.

He was able to infl ict a complete breakdown of blue mussel larvae within hours in water inoculated with poison from the leaves of the Eucalyptus nitens (shining gum) used in the plantations.

This battle has fi nally triggered a response from the Tasmanian government. It has appointed a panel of scientists reporting to the State Premier to review the science. Alarmed citizens have applauded the step, but in the grimy world of politics, what does that mean?

In the meantime, the oyster growers have moved from tidal racks to deep water, and the president of the shire complains about the damage to the district’s tourist industry all this adverse publicity is causing.

The second aquaculture sector hit is at Pomona on the Noosa Lakes system. Gwen Gilson has successfully operated a native fi sh hatchery there for more than 20 years. Over the last few years she began to suffer losses in her broodstock ponds and noticed the embryos developing in the hatchery were mutated.

Images of Twin E, the two-headed fi sh, were fl ashed around the world when the story fi rst broke. You may have seen them. It’s a perfect example of what was happening.

As at St Helens, the problem wasn’t confi ned to fi sh or larvae. Gwen’s farm animals sickened and died. And not just on her farm. Right along her road, Gilsons Road, farmers found the same thing. Chooks, ducks, horses and goats were all affected.

Poultry eggs failed to hatch and distorted embryos were found when they were cracked open. Horses convulsed and died horrible deaths. Well, not every farm along Gilsons Road suffered. One neighbour fronted the other side of the dead-end lane. It was a macadamia nut plantation. Deaths in larval rearing and broodstock ponds coincided with a spray run in the orchard.

It hadn’t always been so. The trouble started when the macca farmer bought himself a new spray rig. His orchard was growing upwards and outwards and he needed more penetration to get total foliage cover. Gwen noticed the spray plume drifted higher than the tallest trees, and mist and vapour found its way across the fence onto her ponds and into the hatchery, as well as the neighbouring farmlets.

As you would expect, human cancers along Gilsons Road have also sprung up. Unfortunately, there hasn’t been a medical champion for them, but Gwen can reel of a list of neighbours who are being treated for a range of cancers.

At the same time, professional fi shermen on the Noosa Lakes noticed Australian bass catches were plummeting. Where previously they could harvest dozens of tonnes of bass they were netting only dozens of fi sh. The mullet catch also declined. Lo and behold, mullet taken from the system for breeding produced deformed larvae in the hatchery.

8 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

ACROSS THE DITCH

… THE ST HELENS STORY IS A

SOBERING EXAMPLE OF HOW CAREFUL

WE HAVE TO BE WHEN WE START

PLAYING AROUND WITH GENETICS

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 9

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S73

The local vet prescribed a course of Atropine injections for Gwen’s livestock. Atropine is the antidote to organophosphate poisoning.

One beast, named Penny, responded to her fi rst injection. “She required fi ve daily injections of Atropine, recovering more after each one,” said Gwen.

The reality was, the vet told Gwen, that Penny would only respond to Atropine if she wasn’t suffering from organophosphate poisoning. Gwen had been to Fisheries, the Agriculture Department, the EPA and Queensland Health with her plight – all to no avail.

She asked Dr Matt Landos to help her. Matt is one of those rare types – a fi sh vet and a damned good scientist as well. He saw Gwen’s excellent photographic evidence needed some science to go with it. He drew up some protocols that would provide the evidence to place before the authorities.

Once confronted with the substantiation of Gwen’s observations, the minister set up a task force, no less. Back in April last year the Noosa Fish Health Investigation Task Force was sworn in. Their fi nal report was to be on the minister’s desk by December 2009.

Are you ahead of me on this one? That’s right, we’re still waiting for the fi nal fi ndings. Talk about a revolving door. Postponed once more – this time till March – it has been replaced with a second interim report.

Google Sunlands two-headed fi sh and see how many hits you get. Gwen’s story was on the Nine Network’s programme 60 Minutes on March 21 if you want to see it on an iPod.

The real issues in both these cases are the risk to the environment and human health, and the authorities’ readiness to bury an obviously grave risk to our very existence on this planet. I for one have been sceptical of

the cries of Frankenstein food from the Chicken Licken’ brigade, and still am. You see, only koalas eat gum leaves. But the St Helens story is a sobering example of how careful we have to be when we start playing around with genetics.

As for the Sunlands events, it exposes just how slack the agencies entrusted with our wellbeing are. The Australian Pesticides and Veterinary Medicines Authority regulates what chemicals can be used, in what manner and at what dosages.

Look up Endosulfan, Carbendazim and see how many countries they’re banned in. Then look up your own governing body’s website and see how widely and under what circumstances they’re used in New Zealand.

By the way, is anyone coming across to Hobart for the Australasian Aquaculture conference at the end of May? See you there. (See news story this issue.)

Oysters on-grown in trays in deep water

enhances growth

Now this is an oyster!

AC28.indd 8 15/2/09 4:52:22 PM

So, have we got that settled, then?

We believe the new Maori Commercial Aquaculture Claims Settlement (Regional Agreements) Act marks

the most signifi cant step in reinvigorating the aquaculture industry that has occurred in the last six years. Granted, that might not be saying much, given the stagnation that has marked this period for the industry.

The second reason we are enjoying talking about this act at Oceanlaw is because we are very proud of the part we played in its development as primary legal advisors to the iwi involved. We have referred to this legislation in earlier columns for a couple of reasons (neither of which is the catchiness of its title).

The act has its roots in the 2004 Maori Commercial Aquaculture Settlement, which guaranteed iwi 20 percent of all new aquaculture space (no sign of that materialising yet), and the equivalent of 20 percent of all “pre-commencement space”, being space fi rst made available for marine farming between September 1992 and December 2004 (including

space applied for during that period, but only granted subsequently).

The act gave the Crown three options for delivering that equivalent to iwi, through:• additional transfers of new space• the transfer of marine farming permits purchased by the

Crown on the open market, or, after 2013• the payment of the fi nancial equivalent value of the space

in question.By 2008, the Crown was prepared to acknowledge it was

going to have to utilise the last of those three methods in the majority of areas.

The iwi of Te Tau Ihu (the top of the South Island) took up the challenge that acknowledgement presented. Ngai Tahu soon joined in and subsequently the iwi of Hauraki. They asked the obvious question: if the Crown was going to have to write a cheque to resolve the issue, why not get the cheque written sooner, rather than later, and allow iwi (and the industry) to get on with things.

The Minister of Fisheries at the time, Hon Jim Anderton,

responded positively to the proposal to resolve the issue before 2013 and an early settlement had been concluded by the end of 2008.

Central to that settlement was some very sophisticated valuation work, in which the iwi were ably supported by Te Ohu Kaimoana and a number of industry insiders who gave generously of their time and expertise. The result is a fair and robust agreement over the value of the iwi entitlements, which will see the Crown paying $97 million in full and fi nal settlement of those entitlements.

The benefi ts of the early settlement for the iwi involved are obvious. With a substantial injection of funds into their coffers, they can get on with investing actively in aquaculture or the wider seafood industry (or indeed, in other industries). The benefi t for the Crown might be less obvious, but it was able to resolve 85 percent of its pre-commencement space obligations under the 2004 settlement, thereby removing a sizeable liability off the Crown accounts.

The Crown also has a new legal option of settling early in other regions where similar agreements can be reached, along with a robust valuation methodology to inform negotiations. The industry benefi ts from the removal of uncertainty around how these issues would be resolved and from potential iwi partners with funds to invest. Finally, the regional economies of the top of the South and Hauraki (in particular) stand to benefi t from the fl ow-on effects of prudent iwi investments.

So, the act really is that rarest of things in law and politics: a win-win-win-win. In our view there are no losers as a result of this innovative and forward-looking development. That is not to say that there are not bigger wins yet to be realised, of course.

Just as 2004 was, 2010 will be a year of change and challenge for the aquaculture industry and iwi in particular as the government attempts to grapple with reforming what might be best described as failed experiments in aquaculture reforms and the Foreshore and Seabed Act.

Much was made by speakers during its third reading of the constructive model the new act provides for all parties working together to fi nd workable solutions to both those challenges. It is to be hoped that that lesson has sunk in.

SETTLEMENTmarks a significant step BY HAYLEY CAMPBELL BSC, LLB, SOLICITOR

Hayley Campbell is a solicitor at Oceanlaw, where she works on a range of aquaculture, maritime and fi sheries issues. As well as her law degree, she has a Bachelor of Science with a

double major in marine biology, ecology and biodiversity.

IN OUR VIEW THERE ARE

NO LOSERS AS A RESULT OF THIS

INNOVATIVE DEVELOPMENT

10 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

14 New St, Nelson. PO Box 921, Nelson 7040. T +64 3 548 4136. F +64 3 548 4195. Freephone 0800 Oceanlaw. Email justine.inns@oceanlaw.co.nz www.oceanlaw.co.nz

OCEAN LAW

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 11

Economics of Aquaculture: GEODUCKS IN PONDSBY HELEN MUSSELY, CAWTHRON INSTITUTE

In the previous issue of NZ Aquaculture, Eric Goodwin and Helen

Mussely presented a new geographical information system tool for identifying potential sites for land-based aquaculture, part of a larger project at the Cawthron Institute on the feasibility of land-based aquaculture in New Zealand. We have also developed bio-economic simulation models to assess the fi nancial feasibility of potential aquaculture ventures.

Bio-economic simulation modelling can be a valuable tool in determining whether a proposed commercial set-up shows fi nancial promise. Using spreadsheet-based models, the biological and fi nancial inputs into an operation can be described and an estimate of fi nancial output generated.

Often this is in the form of net present value (NPV) or internal rate of return (IRR) over a period of 10 to 20 years. In addition, sensitivity analysis can be used to show which of the inputs has the greatest effect on the fi nancial outcome. Instead of using a single estimate, a range of values (minimum, maximum and most likely) can be used for any input value that is uncertain or likely to vary over time.

To illustrate this type of economic modelling, I modelled a hypothetical aquaculture system: the production of the bivalve shellfi sh geoduck (pronounced “gooey” duck) (Figure 1) in land-based ponds.

Such a project might seem far-fetched, but this economic modelling approach makes it easy to screen ideas for further evaluation. In this hypothetical example, 21ha of farm space are developed over seven years. Various costs have been incorporated, including capital costs for land, the intake system and a hatchery, as well as operating costs.

Using the software program @Risk, some inputs were entered as ranges rather than fi xed estimates. For example, the growout stage could vary from 5.5 to 6.5 years, so has been entered as a triangular distribution, where the most likely value is 72 months (six years) and the maximum is 78 months (Figure 2).

This triangular distribution and fi ve other inputs (three biological and two fi nancial parameters) are shown in Table 1. Our model showed that over a period of 20 years, the hypothetical farming entity would generate an NPV of $5,803,398 (using a discount rate of 10 percent) and an IRR of 17 percent.

While these summary statistics are useful, the real power of the model comes from the sensitivity analysis generated by running thousands of iterations of the model with @Risk or other similar software. This allows us to see which variables have the biggest effect on fi nancial performance.

For each iteration, @Risk samples from the probability distribution for each input variable. For example, for growout

time, many more of the iterations would use a value of around 72 months than a value nearer the extremes of the distribution. This in turn produces a probability distribution for the fi nancial outcomes, showing the likelihood of a positive outcome. Once the programme has run the iterations (in a matter of seconds), the results of the sensitivity analysis can be viewed. For our geoduck example, the results for the NPV look like Figure 3.

X <= 76.10

95.0%

X <= 67.90

5.0%

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

0.18

64 66 68 70 72 74 76 78 80

Grow-out time (months)

FRE

QU

EN

CY

FIGURE 2: An @Risk triangular probability distribution for growout time

FIGURE 1: Geoduck

(Panacea zelandica)

0.637

0.541

-0.377

0.295

0.233

-0.125

-1 -0.8 -0.6 -0.4 -0.20

0.2 0.4 0.6 0.81

Greenweight price ($/kg)

Initial stocking density

Grow-out time (months)

Survival (%)

Harvest weight (grams)

Pond excavation cost($/m3)

FIGURE 3: A tornado graph shows sensitivity analysis results

CONTINUED ON PAGE 13

Table 1: Input distributions given for key variables using the program @Risk

Input variable Unit Minimum Most likely Maximum

Time in grow-out stage months 66 72 78

Initial stocking density geoducks/ m2 25 30 35

Survival rate % 30 33 36

Harvest weight grams 650 700 750

Pond development cost $/m3 5 6 10

Greenweight price $/kg 17 20 25

12 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

The success of New Zealand aquaculture is based on being “clean and green” and on being innovative. These two factors have enabled the local industry to achieve

a reputation for its products far in excess of what might be expected from its scale of production, relative to aquaculture worldwide.

The same might be said of the Mahanga Bay Shellfi sh Hatchery, as it was known when it opened in Wellington in 1975, or NIWA’s National Centre for Fisheries and Aquaculture, Mahanga Bay Aquaculture Facility, as it is now called. Clean water and innovation have been equally fundamental to the success of its research throughout a 35-year history of close involvement with this country’s aquaculture industry.

In the early 1970s, New Zealand had little aquaculture production, comprising only rock oysters and salmon and very limited aquaculture research, based in Wellington at the Fisheries Research Division (FRD) of the Ministry of Agriculture and Fisheries.

However, with the predicted expansion of aquaculture production there was a need to develop the technology to ensure seed supplies for both oyster and mussel farmers. In 1973, Duncan Waugh, then the director of the FRD, proposed that the empty shell of the former Defence Department mine store on the shore of Mahanga Bay, Miramar Peninsula, be developed as a research station for investigating rearing and handling techniques for shellfi sh.

As well as the existence of a readily adaptable building, Mahanga Bay also had probably the “cleanest and greenest”, most sheltered and accessible seawater available within the harbour.

The building provided scope for a novel and imaginative use of space, and for research to defi ne the most suitable conditions and techniques for rearing a wide range of shellfi sh, and later fi sh, species.

Throughout the fi rst fi ve years the focus was fi rmly on

shellfi sh, with Peter Redfearn and Bob Watson, aided by Paul Chanley from the United States, successfully rearing the larvae of 15 species of bivalve by 1978.

The next decade saw the focus narrow to paua and mussels. During this period, Len Tong’s paua team developed innovative rearing techniques, systems and equipment which were publicised in a range of scientifi c and popular articles and subsequently taken up by the commercial paua farming industry.

At the same time, mussel research was expanded, and an experimental mussel farm established in the bay for Bob Hickman’s investigations into the relationship between natural plankton production and the productivity of farmed mussels. In the hatchery, experiments by Redfearn and Barbara Hayden investigated spawning, larval rearing and larval behaviour of mussels.

During the 1980s, the hatchery was the country’s only aquaculture research facility. Other agencies, such as the Taranaki Catchment Board and the New Zealand Fishing Industry Board, used it for research and development. Several university students also used it for some or all of their PhD studies. The technical expertise of hatchery staff, such as John Illingworth, in all aspects of seawater reticulation was also widely used.

The 1990s saw signifi cant changes in aquaculture research at Mahanga Bay. New programmes were developed on dredge oysters and rock lobsters, new funding arrangements came about with the establishment of the Foundation for Research, Science and Technology, the fi rst fi n fi sh activity took place with the rearing of juveniles for a snapper enhancement project, and technology transfer (through the publication of Aquaculture Update) and commercial emphasis (on sales of aquaculture products) assumed much greater priority.

Mahanga Bay and the rest of FRD was merged into the National Institute of Water and Atmospheric Research (NIWA) in July 1995. The next fi ve years were notable for a number

Mahanga Bay marks 35 YEARS of research BY BOB HICKMAN

Mahanga Bay in Wellington Harbour is an ideal site for New

Zealand aquaculture research

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 13

of fi rsts, including a red rock lobster puerulus, F1 juvenile snapper, hatchery-reared turbot, pawharu lobster phyllosoma and puerulus and larval kingfi sh. Unfortunately, it was also the fi rst occasion, in March 1998, when seawater had to be brought into the Aquaculture Research Centre by tanker because of a toxic algal bloom in Wellington Harbour.

The fi rst decade of the new millennium has seen continuing changes. In early 2002, Dr Phil Heath took over as manager at Mahanga Bay, following the retirement of long-serving leader Dr Tong in 1999. At this time considerable research effort was focused on producing juveniles in Chris Woods’ project on seahorses; in the work of Woods, Phil James and Graeme Moss on both red and packhorse rock lobsters; and in two new directions for paua research.

These were the work of Moss and Redfearn on selective breeding, and the development by Hickman of a commercially focused seed production unit. An area of skill and experience that Heath brought to Mahanga Bay was recirculation technology, which was rapidly shown to have major advantages over traditional fl ow-through systems for commercial paua culture, as well as having applications in the running of a research centre such as Mahanga Bay.

Diet development, which had been an integral part of the seahorse rearing project, assumed major signifi cance in a programme aimed at producing a diet specifi cally for use in lobster-holding facilities, and was subsequently used to trial on-growing of juvenile rock lobsters in sea cages. Eventually it was modifi ed to form the basis of the diet for James’ project on enhancing the roe of sea urchins (kina).

The full extent of Mahanga Bay’s involvement in the evolution and development of New Zealand aquaculture since the early 1970s is revealed in Mahanga Bay: the life history of an aquaculture research centre, published by NIWA in June 2009.

The history details the facility’s activities from its initial concept through the various changes in research direction, funding and organisation, with numerous appendices comprising documents signifi cant to the history (including several reviews recommending its closure!).

Also included is a list of the names and years of employment of the 111 people (and two cats) who worked at Mahanga Bay from 1974 to 2008, and a further list of “most, but not necessarily all” of the species studied during the same period. It comprises 14 fi sh, four crustaceans, 27 molluscs, three echinoderms, four sponges, eight seaweeds and as many as 50 unnamed species of microalgae.

The list of well over 350 references is noted as being “by no means a comprehensive list of all the publications emanating from Mahanga Bay”. The 17 plates of photographs are equally only representative of the many moments of staff activity captured on camera during the 35 years Mahanga Bay has operated.

Mahanga Bay is still at the forefront of aquaculture research. By continuing with dedicated and enthusiastic staff to be innovative in its new lines of research, it is likely to require redocumenting of its history after a further 35 years of operation.

Mahanga Bay: the life history of an aquaculture research centre. By Robert W Hickman. NIWA Information Series No 71, June 2009. Available as a CD from Publications, NIWA, Private Bag 14901, Kilbirnie, Wellington 6241, or as a downloadable pdf from the NIWA website.

See www.niwa.co.nz/our-science/aquaculture-and-biotechnology/publications

Bob Hickman is a recently retired NIWA aquaculture scientist who spent much of his research career at Mahanga Bay.

Email oysmusturbut.man@xtra.co.nz

NIWA’s well-equipped aquaculture research centre in Mahanga Bay, Wellington Harbour

Mahanga Bay has achieved much in the 35 years since it was developed from a mine store

This type of fi gure is called a tornado graph. Basically, the longer a horizontal bar is for a certain input, the greater the infl uence that input has on the fi nancial outcome. For this example, it shows us that using the distributions given in the table, the most important driver of fi nancial viability received by the farmer will be the green weight price.

This is followed by the initial stocking density, then growout time (the negative direction shows that the longer the growout, the worse the fi nancial outcome). Survival rate and harvest weight are lower in importance again and the pond excavation cost has a relatively minor impact.

It’s about now I hear you asking how realistic my model is and how I knew what values to use for the inputs. In short, it is as realistic as the information it is based upon.

I relied on overseas geoduck farming knowledge and in the New Zealand context this will generate some uncertainty, but the model will indicate this and disclose where improved data would be most useful.

Importantly, the model allows the orderly integration of all available information, an essential exercise when we think about any new aquaculture venture, whether it’s with a new species, new growout technology, or both.

This approach thus supports a more informed decision about whether a pilot project is worth pursuing, and where research and development resources would be best spent for the biggest gains. The model can be continually updated as research and development progresses and new information comes to hand.

By using bio-economic simulation modeling, Cawthron can provide stakeholders with a powerful and critical tool for assessing the feasibility of potential aquaculture operations.

CONTINUED FROM PAGE 11

14 ■ NZ AQUACULTURE ■ MAY/JUNE 2010

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efficiency through triploidyBY SAM GALE, SERENA ADAMS AND ACHIM JANKE, CAWTHRON INSTITUTE

Cawthron has been working on triploid shellfi sh with Pacifi c Marine Farms, the Marlborough Mussel Company, Waiheke Fresh Seafood and Aqua

Developments. Our efforts are now coming to fruition, with commercial volumes of triploid Pacifi c oyster spat being sent out to industry partners for fi eld testing later this year.

Cawthron has linked this work with its existing selective breeding programme and produced selectively bred triploids. This will provide the New Zealand industry with an advantage over competitors such as the United States, France and Australia, where these pathways of gaining genetic improvement have not been interlinked.

WHAT EXACTLY ARE TRIPLOIDS?Triploid animals contain three sets of chromosomes (3N). Animal cells normally contain two sets of chromosomes (2N) and are termed diploid. Cells containing more than two sets of chromosomes are called polyploid. Polyploidy can occur naturally and is regularly utilised in horticulture.

It can also be induced, but animal breeders do not use it often because of the low number of eggs available and their inaccessibility. Fortunately, shellfi sh release millions of eggs and sperm for external fertilisation and are therefore amenable to triploidy.

WHY PRODUCE TRIPLOIDS?Diploid shellfi sh spawn and thereby lose condition. This affects their fl avour and appearance, and renders them unmarketable. For oysters, this generally means growers stop harvesting in the middle of summer. On the other hand, mussels tend to lose condition during winter. This disadvantages growers and processors, as operations are limited by these seasons.

Triploid animals do not spawn and are effectively sterile; their odd number of chromosomes makes it impossible for them to produce regular sperm and eggs. Energy normally put into reproduction is diverted instead into general tissue growth and carbohydrates, which makes the shellfi sh fat year-round and faster-growing. Triploids are thus available for harvest all year, leading to signifi cant improvements in production effi ciencies.

The benefi ts of growing triploid shellfi sh, particularly Pacifi c oysters, have been realised by producers throughout the world. In the main oyster-producing countries, such as the United States and France, more than half the industry has converted to triploids and efforts are underway in Australia to convert the industry to triploids there also.

HOW ARE TRIPLOIDS PRODUCED?Triploid shellfi sh (3N) are produced by administering a chemical, heat or pressure-shock treatment shortly after fertilisation, or by crossing tetraploid broodstock (4N) with diploid broodstock (2N).

Following a recent Cawthron breakthrough, we have a method that enables us to routinely produce high triploidy rates for Pacifi c oysters. We can obtain 100 percent triploidy (3N) larvae on a commercial scale. Spat from the latest larval batch are currently growing at Cawthron’s Glenhaven Aquaculture Centre. At 8-10mm they will be transferred to farms of collaborating industry partners to assess grow-out performance and other qualities under commercial conditions. Waiheke Fresh Seafood tested a pilot batch of triploid oysters last year. According to the company’s director, Nat Upchurch, they showed excellent fatness and condition at a time when standard diploid stock was spawning and had become unmarketable.

Worldwide, the most common method used at commercial scale to produce triploids is by crossing tetraploid broodstock (4N) with standard diploid broodstock (2N) – a complex, time-consuming process that can take fi ve to 10 years to produce harvestable triploids. In contrast, our novel procedure provides instant results. Moreover, we can take advantage of the superior oyster lineages we have developed through our selective breeding programme. Our recent triploid spat have been

INCREASING PRODUCTION

MAY/JUNE 2010 ■ NZ AQUACULTURE ■ 15

produced from the same two best-yielding breeding lines from which we produce our commercial diploid spat.

CONFIRMATION OF TRIPLOIDYIt is critical that the ploidy status of larvae is determined quickly and accurately so labour and resources are not wasted on batches of larvae with low triploidy rates. Triploidy status can be determined in a number of ways, but the easiest is by using a fl ow cytometer, which measures fl uorescence. Larvae are prepared and stained with a DNA-specifi c fl uorescent dye. Triploid cells can readily be distinguished from diploid cells because their fl uorescence signal is 1.5 times higher.

THE FUTUREFurther experiments are planned to allow pre-screening of oyster broodstock to select those that will consistently yield 100 percent 3N larvae. In addition, we will confi rm that 3N oysters consistently deliver the promised benefi ts across different growing environments and conditions. The successful conclusion of these trials will result in triploid oyster spat becoming available commercially in New Zealand.

After successful triploid work in Pacifi c oysters, we intend to do the same with Greenshell mussels. Again, we will be looking for high levels of triploidy, improved growth rates and an extended harvest season.

ABOVE: Triploid oysters checked by Pacific Marine Farms in January 2010 after eight months of ongrowing

BELOW: Cawthron’s flow cytometer ploidy analyser in action

The marine farming industry, which is desperate to add value to existing water space, is eagerly awaiting aquaculture reforms, says the Marine

Farming Association’s chief executive, Graeme Coates.He told the Marlborough Express that the mussel

farming industry is at a crossroads. “We’re battling, there’s no doubt about it.”

Coates hopes aquaculture recommendations by a Technical Advisory Group report, which is expected to be introduced to parliament later this year, will allow farmers to add value to their farms.

The group was established early in 2009 to provide the government with recommendations on how to kick start the sustained development of aquaculture.

Following a moratorium on new aquaculture permits in 2001, growth of the industry has stalled since reforms in 2004, with no new applications for aquaculture space in Marlborough in the last six years.

The report also recommends allowing marine farming for more species. “We are not so interested in increasing the amount available, we are more interested in increasing the value,” says Coates.

While fi n fi sh farming has been identifi ed as being more profi table, Coates doesn’t see an exodus from mussel farming in the Marlborough Sounds in the immediate future, because suitable, sustainable species have not been identifi ed for many sites.

However, current production has met international market needs, so value-added mussel products are the key, he says. “This is a fantastic product, but it has historically been treated as a frozen export product and we need to turn it into more of an everyday household protein eaten fresh or ready to eat.”

Health supplements are another option, says Coates, who has been involved in New Zealand aquaculture since a foray into eel and oyster farming in 1976. Wattie’s Industries later employed him to develop commercial salmon ranches in the South Island, before he headed to Scotland, where he worked as the general manager for an aquaculture consulting company. He eventually moved back to Blenheim because it was close to the fl edgling mussel and salmon farming industries.

Coates has been involved with the Marine Farming Association since 1998. The association is similar to a Federated Farmers of the sea, representing marine farmers at the top of the South Island.

It has acted as a sounding board, consultant and lobbyist for its 130 members for the last three decades.

“I bring a lot of international knowledge, backed up with a wide knowledge of what happens on a marine farm, along with a lot of personal skills: dispute resolution, discussion and problem solving,” says Coates.

He says one of the biggest challenges has been getting the industry regarded as a legitimate and important activity in the region.

“This industry is going to occur whether people have strong views or not. We need to do something so people have access to greater quantities of seafood.”

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