Submission to Board of Enquiry in favour of the King Salmon Company Ltd's Salmon Farming Plan for the Marlborough Sounds - Clive E Barker
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Submission to Board of Enquiry in favour of the
King Salmon Company Ltd’s Salmon Farming Plan
for the Marlborough Sounds.
Clive E BarkerSUBMISSION - NEW ZEALAND KING SALMON PROPOSAL
I am in favour of diversifying acquaculture in the Marlborough Sounds by way of increasing salmon
culture.
My name is Clive Barker. At Takaka, I commenced the first commercial salmon farm. This also
entailed producing all our fish food on site. I travelled to America to review the fish food production
and salmon culture methods as at that stage these people were the leaders in innovation in salmon
feeds. The Abernathy Salmon Research facility, plus the Washington State University, Oregon State
University, and two private food producers, gave me the information to proceed with confidence. I
was the first person to produce a captive salmon brood stock and supplied salmon eggs to several
other early salmon farms in the very late 1970s and early 1980s. I have also grown rock lobster and
paua in captivity, to sexual maturity, producing my own food formulations. I am the only person in
New Zealand who has grown salmon in land-based raceways and silos in both fresh water and sea
water. I have also used water re-use systems and temperature-control for growing rock lobster, and
have grown plankton to feed Artemia for cyst production that were processed to be sold to produce
live food for larval marine fish.
While not at present actively engaged in fish farming, I still take an interest in aquaculture and when
travelling overseas have visited universities, aquaculture research centres and farming sites. This has
included seven countries.
Fifty years ago, 1962, the world population stood at 3 billion, by 2012 7 billion, and in 38 years time,
2050, it is reported there will be 10 billion. Feeding this increasing global population requires that
the food supply has to increase by at least 40%. Add in here the burgeoning middle-class of Asia
switching to a more upmarket protein-based diet.
Millennium Ecosystems 2005 report – the vast oceans that cover 70% of the earth’s surface
contribute less than 2% of our food, feeds, and biomaterials. In contrast 24% of the global land area
produces over 5 billion metric tonnes of biomass annually for human use, of which over 90% is from
plants. This illustrates the current limitations and potential opportunity for the cultivation and
harvest of the ocean’s resources.
1|PageThe US Global Change Research Information Office estimates that the soil in the USA is being eroded
at 17 times the rate at which it forms. Soil erosion rates in other parts of the world are twice as high
as in the USA. The point is that terrestrial agriculture is not looking currently sustainable and live
stock raising is on a particularly troubling trajectory because of its ecological inefficiency.
Public perceptions of marine aquaculture operations differ around the world. In Asian and
Scandinavian countries acqua farms are viewed as a sign of prosperity, here in New Zealand they are
viewed with suspicion and hostility.
One of the features of traditional aquaculture as it has evolved in China over two and a half
thousand years is the development of what we now call integrated aquaculture or polyculture. Their
aquatic food production systems were all parts of a complex integrated ecosystem, that has clearly
been sustainable over a very long time. A key issue for aquaculture activity is to reduce the negative
view of this activity in future mariculture ventures. What farms need to accomplish is the integrating
of waste and cleaning organisms attached to each farm. I personally believe that integrated systems
such as seaweed culture and possibly rag worm culture, plus the present shellfish culture, will be
more integrated into the overall salmon culture concept. While not necessarily on the same site but
the general area. Seaweed has only recently been given the green light as a culture species in New
Zealand. There is a wealth of information on the nutrient uptake of seaweeds. A brief overview
(World Bank Project( is three tonne of wet seaweed utilises 1.27 tonne of carbon dioxide, 0.22 tonne
of nitrogen, and 0.03 tonne of phosphorus, and also see “Seaweeds and their role in Globally
Changing Environment”, J Secbach (Springer). It has to be acknowledged that mussels filter around
four litres of water per hour. To do the sums, there are 800 million plus shellfish in the Sounds, this
is a lot of water filtered each day. Fisheries scientists in both Maryland and Virginia said to me they
only wished longline shellfish could be practised in Chesapeake Bay, to help the system. The over-
fishing of their shellfish has completely changed the health of the Bay water.
The most important feature in marine fin fish culture is choosing the right site. This is the most
fundamental aspect of aquaculture strategy and determines the success in both mitigation of
environmental problems and profit levels for the farm. Oxygen levels and water flow for any fish
grown in containment are of paramount importance. It is this feature that limits a site’s acceptability
for fin fish culture. Whereas the air we breath has 21% or 21 grams oxygen per 100 grams air, fish
have to survive on 0.0008% or 8mg of oxygen per 1000 grams water. At the land-based salmon
facility at Lake Grassmere, oxygen was injected into the incoming sea water supply when required,
so as to reduce the cost of pumping the extra water at the times of higher water temperature, thus
2|Pageless oxygen. To produce a cubic metre of oxygen from the air via zeolite gas separation is a fraction
of the cost to pumping a cubic metre of water. This is why sea cage culture at the right site is
acceptable for farming fish, nature moves the water at no cost. Oxygen is always the first limiting
factor and dictates an acceptable site.
The advantage of the sea water flow is that it moves in a block, it is assumed that the flow at
different depths has been established. A 50m x 50m cage 15 metres deep has 37,500 cubic metres of
water space. Given a flow of 0.13 knots (0.07 m/s) will result in five exchanges per hour – 37,500 x 5
= 187,500m3.
187,500m3 x 1000 = 187,500,000 l/hr x 24 = 4,500,000,000 litres per day. Oxygen in, 8mg/litre and
oxygen out, 4mg/litre, therefore 4mg O2 available to fish or 750kg/hour or 18 tonne/day.
The other factor is the dilution of the waste production from the catabolism of the food protein into
the marine environment. Research has shown it takes 250gm oxygen to metabolize 1kg food that in
turn produces approximately 30gm of ammonia NH3. A quick look at feeding 6,000kg food/day
utilizes 1.5 tonne O2 and produces around 180kg NH3. The method I used at Grassmere to establish
pump water flow when injecting oxygen so as to make sure ammonia levels did not climb too high
with the reduced water flows.
kg food fed x 0.0289 – 6,000kg x 0.0289 = 173.4 kg/NH3.
Another method used by Japanese seaweed/fish culture
kg food x food protein% x 16% (N in protein)
6,000 x 0.35 x 0.16 = 336kg TAN in food
Amount retained by fish = weight gain x protein in fish x 0.16. However I do not have these figures so
will use generally accepted levels of food distribution.
Protein retained by fish 38% with 44% excreted as ammonia plus 18% undigested protein or released
from solids = 62% to the environment.
336 TAN x 0.62 = 208.32kg/day x 1,000,000 = 208,320,000 mg NH3/day.
3|Page208,320,000mg ÷ 4,500,000,000 litres/day = 0.0463mg NH3/litres day to the environment.
Dilution 1:21,598,272 not a lot to worry about even if the feed rate is three times this amount at the
flow rate 0.07 m/s, there would still be no more than 0.138mg/litre/day, dilution 1:7,246,000.
The effects of dissolved nutrients are considered negligible and are used by macro and micro algae
plus other marine life. In fact if utilized correctly will increase bio-diversity. Having grown micro
algae cells it takes 1-2 days for a cell to divide under normal sea water conditions. It takes 8-9
generations or days to go from 1000s to million cells per ml. In eight days with a water flow of just
3cm, the cage water would have travelled 20km from the farm and would have well and truly mixed
with other sea water. Algae blooms are extremely unlikely. This dilution factor is accepted for
human sewage outfalls that also contain toxic chemicals from households and commercial
industries. It has to be asked, both the Picton Freezing Works and town dumped their waste into
Queen Charlotte Sound for years - were there any major problems? I would believe the BOD would
have been very high from these effluents.
The discharge of nutrients from aquaculture operations have been erroneously recalculated into
person equivalents. The waste load from aquaculture has a totally different CPN ratio and the ratio
between particulate and soluble wastes are essentially very different, the comparison is not relevant
(Rosenthal et al 1995). Nutrients from sea cages are widely dispersed quickly and taken up and used
by the marine food chain that has been in operation for a billion or more years much more
effectively than the waste from terrestrial animals.
We have countries like Norway that over the last 15 years have increased sea cage production from
200,000 to 900,000 tonne and last year they expected to pass 1,000,000 tonne salmon and trout,
plus they also culture 5,000 tonne of a mix of Halibut, Turbut, and Cod and Artic Chair (Recent
Growth Trends and Challenges in Norwegian Aquaculture Industry: AES News 2011). If there was to
be a major problem caused from dissolved nutrients it surely would have shown up by now. The
other factor to review is seaweed harvest/culture. This is the practice of most high volume fish
aquaculture countries (15.8 million tonnes seaweed 2008 FAO statistics, 93.8% from aquaculture).
While the dissolved nutrients from sea cages are generally taken care of the aspects of solid waste
input into the sediment can lead to a number of changes in the chemical and physical parameters to
the sea floor. To my knowledge there has been at least 30 scientific studies by different scientists on
marine sea cage environmental effects from Doyle et al 1984 to Nickell et al 2003. These were
4|Pagestudies that reviewed farms in Norway, Scotland, USA, Canada, Mediterranean region, and Chile. The
general overall findings were the major impact zone to the sea floor was restricted to under the
cages and a small distance of a few metres beyond, with some minor effect up to 20-50 metres. Both
Morrisey and then McGhie found a 12 month fallowing period was sufficient to return to pre-farm
conditions. I believe this aspect has been well covered by others. The King Salmon Company has
undertaken and it says will continue to monitor the sea floor at its present and future sites. Good
management practice together with selecting sites with a natural low biological oxygen demand and
high flows will mitigate most environmental effects.
Rapid advances in aquaculture research and the development towards sustainability with new feed
delivery systems plus pellets no longer packed with more nutrition than the target fish can use and
pellets designed to stay longer in the water column have greatly reduced bio-deposits from salmon
cages. One fishery’s scientist in Norway said to me the ideal fish food pellet would be one that sinks
slowly, then at the bottom of the cage rises to the surface again. Here is a challenge for someone to
make a name in aquaculture. The use of fishmeal as a feed ingredient appears to upset some people
stating this food item makes fin fish farming unsustainable. Even if fishmeal was completely
eliminated from aquaculture feeds it would continue to be produced for land animals. Aquaculture
has simply reallocated the fishmeal production and not increased the total amount of pelagic fish
harvested for use in fishmeal, which historically is 6-7 million tonne annually. Poultry and pigs that
once used 88% or more (New and Csaves 1995) of the fishmeal production now use 57%,
aquaculture 34%, with 9% for other uses (Eleni Mente et al 2006). There is the argument these fish
could be used for direct human consumption. If this was so they would have already had some local
use but the truth is no locals wanted to eat these fish. Here is New Zealand we have the Lantern
fishes. Fisheries Research surveyed these in the late 1970s and reported there were thousands of
tonnes of this fish that could be utilised for oil and meal. I notice there is no rush to use these fish in
fish and chips shops.
Fish are one of the most efficient converters of food to flesh. The reasons being:
(a) The energy cost to keep warm is not required in fish;
(b) The low energy cost of locomotion. Fish have no need for large anti-gravitation muscles in
their weightless aquatic environment;
5|Page(c) The low energy cost of reproduction in fish which takes place outside the body. Salmon and
trout produce 3,000 to 6,000 offspring annually, a cow only one;
(d) The efficient mechanism possessed by fish for protein catabolism and the excretion of waste
nitrogen. Whereas warm-blooded terrestrial animals utilized considerable energy cost to
convert ammonia to urea, and then uric acid which must be further concentrated and
excreted by the kidneys, fish simply excrete nitrogenous waste via the gills from the blood to
the water with little to no energy expenditure.
Nothing in life is 100% risk free but the gain may be worth more than the risk, especially when the
consequence of something going wrong is miniscule. To feed future generations is not without some
environmental risks and effects. The wild capture fishery is in decline, farming is the best alternative
to increase production. FOA states there are 177 species farmed at present.
What constitutes acceptable risk?
The environment risks associated with net pen aquaculture has to be put into perspective with all
the other ways of producing protein foods, to determine what constitutes acceptable environment
effects, caused by aquaculture.
I have listened to the one-dimensional demand for zero risk aquaculture expounded by some in the
community who demand that aquaculture be conducted with no environmental effects. In my
opinion it is this “no allowable effect” approach to feeding future generations that is unsustainable –
not aquaculture.
How do these environmental costs compare with the costs associated with other forms of food
production? The question then becomes one of whether or not the production of 1,200,000kg of
salmon providing society with 1,000,000kg of high quality food was worth the partial loss of benthic
production for a distance of 120 metres. To put this into perspective the net pens footprint for a
farm producing 1,200 tonne of salmon would cover 0.5 hectares. Taking into account changes
outside the cage site that may be impacted would be no more than two hectares. If we now review
the production of 1,000,000kg of edible beef, it takes around 0.8 hectares to produce a slaughter
steer weighing 550kg and this steer will produce about 250kg of edible meat. The point is, that
1,000,000kg of edible salmon is equivalent to 4,000 prime steers in terms of human food. It would
take a total production of 3,200 hectares of good pasture land. If this is a new development, then
6|Pagethe diversion of 3,200 hectares of native bush and scrub to be cleared will result in eroded soil into
our streams to work downstream to further increase the suspended sediments in our rivers and
estuaries.
What is the bottom line?
The bottom line is the environmental cost of producing 1,000,000kg of edible salmon and 500 to
1,000 tonnes seaweed (sold at 10c/kg, worth $50,000 to $100,000, and removing 212-424 tonnes
carbon dioxide plus 37-74 tonnes nitrogen and 5-10 tonnes phosphorus) is the partial degradation of
two hectares of deep water seafloor. While the cost of producing an equivalent amount of beef is
the diversion of 3,200 hectares of bush from wildlife habitat to pasture, and a decade long (or
longer) degradation of our streams, rivers, and lakes due to a bed-load of eroded soil.
From an environmental effects point of view, the efficiency of salmon culture to produce new high
quality protein food becomes immediately obvious A similar analysis for other types of terrestrial
agriculture would yield similar startling comparisons.
The increasingly scarce food producing resources of land, water and energy will force new methods
and management to increase the production from our marine environment. The marine eco-system
is going to become an important opportunity for new employment in the food, recreational, and
biomaterial industries. New Zealand has to grow up to meet the challenge.
To sum up, from an environmental standpoint animal husbandry is much more damaging than most
modern aquaculture practices. The farming of the aquatic environment will become more important
for both food security and new employment opportunities as populations continue to increase.
However this will require the building of a comprehensive knowledge in a number of biological,
technical, commercial, and socio-economic areas, starting in our high schools. This will lead to a
genuine grown-up debate around new aquatic technologies based on evidence, not prejudice.
The only fault in the King Salmon Farm’s submissions? I have been unable to find references to the
questions – cubic size of cages; water oxygen saturation at sites; how many water exchanges per
hour through cages is anticipated at farm sites, minimum and maximum.
7|PageREFERENCES
Antonio Gouveia : Aquaculture and the environment : aquaculture Europe 1998 Vol. 22 (3) p6-4.
H Kimura and M Notoya : Ulva pertusa and Undaria undarioides seaweed culture for reducing
nitrogen from fish culture in Wakayame Prefecture Japan.
Eleni Mente et al : Effect of food and feeding in the culture of Salmonids on the marine environment.
Aquacult. Int. 2006 14,. p499-522.
Michal New; Jmre Csavus : Will there be enough fishmeal for fish meals, aquaculture Europe 1995
Vol. 19 (3) p6-11.
VAP Simha : Carbon dioxide utilization and seaweed production. World Bank project.
AGT Tacon : M Matian : Global overview on the use of fishmeal and fish oil in industrially
compounded aqua feeds. Aquacult 2008, 285 p146-158.
Millennium Ecosystems 2005 : US Global Change Research Office, both open access on the web.
Seaweed and Animal Nutrition : Algo Rythme 2005 No. 72(4)
Seaweed Health Food of the Future : Algo Rythme 2002 No. 59(3)
Innovation : Algo Rythme 2007 No. 79(3)
World Review of Fisheries and Aquaculture 2010 FAO
Bjorn Braaten, Chapter 3 Cage culture and environment impacts.
Aquaculture Engineering and Environment Ed. A Bergheim.
K M Brooks : Assessing the Risks, Northern Aquacult 2001 (12) p3
Rosenthal H : et al. Aquaculture and the environment : in cold water aquaculture in Atlantic Canada :
(Ed Boghen A D) 1995 p451-500.
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