Download The New Zealand greenlipped mussel aka the Greenshell mussel is

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‘GREENING THE MUSSEL’
A Presentation to the Institute for Social Economic and Ecological Sustainability
Aquaculture Workshop, University of Minnesota, July 2003.
“North America's most commonly eaten mussel, is the green-lipped mussel, Perna
canaliculus.
Perna canaliculus is related to the Perna viridis of Asia and the Perna perna of
South America; but is unique to New Zealand.
Before European colonisation New Zealand was known as Aotearoa (“Land of the
Long White Cloud”) by the indigenous people: the Maori. Aotearoa, formerly part of
Gondwanaland, was unique in that it had no mammal population except bats and the
only protein food sources were birds, coastal shellfish and seafood.
The green-lipped mussel was prolific around New Zealand's coastline and formed a
major part of the Maori diet in cooking styles sometimes reminiscent of early
American clam bakes.
From early colonisation in the 1800s through to the mid-1900s feral Perna
canaliculus populations remained strong.
But in the 1960s researchers in the USA were investigating potential anti-cancer
agents derived from marine organisms. Their research into Perna canaliculus found
no anti-cancer activity but did note the presence an anti inflammatory activity.
As a result, during the 1970’s and 1980’s the harvesting of green-lipped mussels for a
mussel extract marketed for its antiarthritic values resulted in the decimation of New
Zealand's feral populations.
Aquaculture experts from the University of Washington USA were commissioned by
the New Zealand government to work with New Zealand’s marine farming pioneers
to develop a marine farming system suitable for the New Zealand's species and the
New Zealand environment.
In the 1980s the USFDA ruled that the mussel extract should be classified as a
medicine, not a food. Imports into the USA were immediately stopped and the
industry virtually collapsed overnight.
Focus turned to marketing mussels as a food. Exports started slowly, developing
through the late eighties and nineties until it became a thriving industry again. Exports
in 1988 were NZ$4 million and in 2002 had reached NZ$185 million.
Since then the New Zealand industry has become one of only five countries approved
by the USFDA's National Shellfish Sanitation Programme; has developed a world
leading voluntary Environmental Management Strategy and Code of Practice; and has
a proven Algal Bloom Monitoring Programme.
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Perna canaliculus produced within the Programme is marketed internationally under
the industry-owned ‘Greenshell’ trademark.
The industry now exports processed ‘Greenshell’ mussels to more than 64 countries;
and is New Zealand’s second most important seafood export crop.
The NZ green-lipped mussel population has an average "standing crop" of 200,000
tonnes online at any one time. Approximately 80,000 greenweight tonnes is harvested
annually. Of this around 50% is exported to the USA in a value-added frozen half
shell form.
But this highly successful industry has the most amazingly fragile annual “genesis”.
At present 80% of the industry's annual spat requirement is collected from one beach,
Kaitaia. Hundreds of tonnes of spat-covered seaweed wash up on to the beach each
year. If not gathered most of the spat dies on the beach.
This has been the seed-stock for the industry since its inception. Farmers are now
using special techniques to gather spat from around their own farms and some
industry members are researching spat hatchery and nursery systems.
As a result of natural genetic variability and evolution, spat taken from various
farming areas have evolved subtle differentiations from the annual Kaitaia stock.
This natural variability is regarded as good by the industry. It strengthens the brood
stock, ensuring and strengthening sustainability of the species.
The industry had been centred on the Marlborough Sounds, and 80% of the national
production still comes from this area. But the industry has recognised the
vulnerability of a “mono- site” for negative environmental impacts. This has meant
the conscious development of farms in other parts of New Zealand.
There are now four main coastal areas of production: Coromandel, Marlborough
Sounds, Golden Bay and Stewart Island. An exciting development currently
underway is the investigation of submersible deep-water offshore farms.
Although mussel farms have a visual impact on the environment (mussel floats)
current research shows minimal other impact.
There are virtually no predators that effect Perna canaliculus when they are grown on
ropes. Starfish are a problem only where mussels are too close to the sea bottom.
There is some stripping of young mussels off the ropes by juvenile fish, especially
snapper, but this is overcome by seeding the lines at a time when the juvenile fish are
not prevalent.
Algal blooms are not an issue for the mussel itself. Blooms can be a rich source of
nutrient for the mussel. The issue is more about humans eating mussel meat while
toxins are present in the meat. Once the bloom has gone and the toxins cease to be
produced by the mussel, the mussel is perfectly safe to eat.
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The mussel industry itself has proved to be a boon for small coastal communities in
New Zealand; especially Maori communities. The industry has a very high labour
component providing unskilled and semiskilled employment, plus managerial,
technical, scientific and marketing employment opportunities.
And so from the above it can be seen that the green-lipped mussel is a naturally
occurring indigenous shellfish that has formed the basis of prosperous, respected and
internationally successful New Zealand industry. It is an industry based on a strong,
voluntary sustainability ethic.
But could or should the New Zealand green-lipped mussel be eligible for “organic
status”.
It is clearly very low on the food chain: it is at the very start of the process by which
sunlight energy and phytoplankton create a complex variety of foods for humanity.
Whether or not it is philosophically "organic" means understanding why “organics”
developed and the relevance of that to aquaculture.
Organics developed as a reaction to the "MUCk” of industrialised agriculture ie the
focus on Monocropping, genetic Uniformity and insensitive Controls (such as a broad
spectrum pesticides weedicides etc). Instead, advocates of organics argued for variety
diversity and adaptation.
From this alternative philosophical approach it can be seen that “organics” is not
about control but about governance.
Noss, Wild Earth magazine (Noss 1987, 1990), argues that organics should be
involved with maintaining viable populations of native species; of maintaining
ecological processes including nutrient cycles and even natural predation, that
production systems should be designed and managed to be responsive to short and
long-term environmental change and importantly, to allow evolution of a species.
Mussel farming as practised by some New Zealand farmers clearly meets all of Moss’
definitions.
The argument exists that an organic product has to have something different about it
when compared to its non-organic ‘brother’ or ‘sister’.
But the issue is less about the organism than about the process of production: it is
about context more than content.
We have to accept that the issue is governance and not control. We have to accept that
it is no more logical to assume control can exist in an open-air land-based agricultural
production unit than in an open-sea aquaculture production unit’. From insects and
rodents, to free pollens small birds and animals... encroachment of an organic enclave
is never-ending: it is not controlled by waving a certificate at nature in King Canute
style.
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And so it is a question of philosophical intent; of a commitment to put in place
practices that allows the producer to understand at all times what is happening to the
environment and the organisms. And to make choices that advantage both.
In New Zealand the Sealord Shellfish Company, for example, has for the last eight
years been applying a comprehensive innovative farm monitoring program to its
mussel production units.
In summary this programme monitors, on a fortnightly basis, temperature,
salinity,mussel growth and condition and chlorophyll in its farming areas. It does this
in a ‘water-column stratification model’ that assesses those variables at 1, 5, 10 and
15 metre levels. At the same time mussel samples are taken from those levels and
checked for physical dimensions as well as being cooked to a standardised process
that creates a measurable "condition index".
The result of this significant monitoring program, matrixed against external variables
such as climate, neighbouring land use and changing water use, is providing the
Sealord Company with an exceptional understanding of both the influence of its
mussel farms on the environment and vice versa. The management of farming
activities is matched to the capabilities of the environment to sustainably support
farming operations. This work is ongoing and constantly improving both productivity
and the health of the natural environment.
Such a comprehensive and all embracing approach to understanding the environment
has also had a major benefit to all the stakeholders of that environment. As a filter
feeder the mussel is highly sensitive to the seawater ‘gestalt’: it is the equivalent of
the "coalminers canary”. The industry with its multimillion-dollar investment has
become a guardian of the sea, monitoring for any negative activities by other resource
users and being in a position to demand retractive and corrective action by other
resource users.
Such a commitment to governance and the sympathetic and responsible use of the
environment for economic purposes surely meets the principals and the objectives of
the organic philosophy.”
Ends.
Presenter: Bill Floyd
Director, Floyd Marketing Ltd, New Zealand
Seafood menu strategist,
Contract Manager, Sealord Shellfish New Business Unit.
Email: [email protected]
July 2003
Acknowledgement: My thanks to Fred Kirschenmann for his mindful and paradigm
changing paper, ‘Philosophy Underlying Certification of Wild Harvested Organisms”,
ISEES 2000. My own thoughts, and this paper, Greening the Mussel, borrow heavily
from that.