New Zealand Trout Farming Industry Analysis

This assignment provides a detailed overview of the trout farming industry in New Zealand. It examines the country's target for a net profit of one billion dollars from aquatic fish, which can be achieved through government support for trout farmers. The document references various sources, including research articles, industry reports, and government publications, to discuss the biological costs and benefits of using triploid rainbow trout in aquaculture. It also touches on the economic analysis of rainbow trout aquaculture farms and the importance of land-based aquaculture assessment frameworks in New Zealand.

Running head: AQUACULTURE 1
Aquaculture of the Trout (Rainbow Trout)
(Author’s name)
(Institutional Affiliation)

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Biology of the Rainbow Trout and key factors for cultivation
The Rainbow Trout(Oncorhynchus, mykiss) is a North American native fish to Pacific
drainages that runs from Alaska to Mexico(Parol, Pietrzak-Fiecko & Smoczynski, 2014). It has
been introduced to other continents and countries since 1874 where most of the trout fisheries are
maintained and cultured(Parol, Pietrzak-Fiecko & Smoczynski, 2014). The rainbow trout has a
wide range of tolerance in different environments since it is fast growing, hardy and easy to
pawn and can be easily weaned to artificial food(Tower, 2012). The rainbow trout is capable of
occupying a wide range of habitats ranging from rivers, lakes, and streams. It has a capability of
archiving a rapid growth where within a period of about three to four years, the weight of a
rainbow trout can be 7 – 10 kg(Omaima Harun, Zou, Zhang, Nie & Secombes, 2014). The fish
is capable of withstanding a range of temperatures starting from 0-27 degrees(Tower, 2012).
However growing and spawning only occurs in a narrower range of between 9-14 degree
Celsius(Parol, Pietrzak-Fiecko & Smoczynski, 2014). The optimum temperature need for a
rainbow trout is around 21 degrees Celsius. Due to this characteristic, rainbow trout is highly
influenced by temperatures and food availability in terms of growth and maturation making the
maturity age to vary between 3 – 4 years(Omaima Harun, Zou, Zhang, Nie & Secombes, 2014).
The female trout has a capability of producing over 200eggs per kilogram body weight.
The rainbow trout eggs are generally large in diameter ranging from 3 to 7 mm(Berrill,
MacIntyre, Noble, Kankainen & Turnbull, 2012). Most of the fish only spawn once although
research has been done and various bleeds developed which can spawn throughout the
year(Omaima Harun, Zou, Zhang, Nie & Secombes, 2014). Rainbow trout can develop superior
characteristic through cross bleeding which may end up increasing growth rate, resistance to
diseases, improvements in meat quality and taste, prolificacy and weight(Tower, 2012). Several

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countries like the United State have also developed a genetic manipulation of rainbow trout
embryo sex chromosomes that lead to the production of triploid females which do not possess a
characteristic of hook-like jaws ensuring customers attraction(Omaima Harun, Zou, Zhang, Nie
& Secombes, 2014). Rainbow trout do not naturally spawn naturally in the culture system
making the juveniles to be obtained by the collecting eggs from a wild stock or from the artificial
hatchery(Tower, 2012).
Environmental and Culturing Conditions
Different populations of a rainbow trout will require various habitats including small to
large livers, cool lakes, cold headwaters, oceans, and tributaries(Heather, 2012). Rainbow trout
will use almost all these habitats depending on the genetic habitants and trout population(Tower,
2012). The prime rainbow trout water habitats are usually clear, clean and cold(Berrill,
MacIntyre, Noble, Kankainen & Turnbull, 2012). Rainbow trout rely on different types of food
substances making them be opportunistic feeders. Their feeds range from small insects to
crayfish( FAO ,2015). The advantage of farming rainbow trout in the artificial pound is that they
quickly adapt to different types of artificial food provided. Rainbow trout normally spawn in
main river channels and in lakes tributaries including both inlets and outlets( FAO ,2015). This
usually happens once or twice in a year during the spring and early summer. The female rainbow
trout normally lay a portion of her eggs where male will later pass on and fertilize them(Heather,
2012). Farmers can harvest juveniles later and take them to their fish ponds. Rainbow trout do
not spawn on the fisheries thus the juveniles can only be artificially hatched or collected in the
tributaries(Heather, 2012). A sufficient water depth is required in the tributaries to ensure the
eggs get enough oxygen and the metabolic waste can be freely be removed.

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The ideal intersection of habitat components will require a cool and clean water. with
overlapping riparian vegetation on the undercut banks(Heather, 2012). The water should be
slow- flowing to deep pools with one to three-inch diameters gravels. In addition, aquatic weed
beds are required with submerged branches or logs(Tower, 2012). Since the rainbow trouts are
more solitary than social, more partitions should be used with small sizes and territories allowing
more fish to coexist during the winter periods. Deep sides of the pools are important during the
winter survival(Hayes, 2013).
A study by Dr. Hayes in 2013 concerning trout spawning in Wellington region proved
that New Zealand can make a great environment for rainbow trout farming (Fish and Game
Organization ,2018). The study demonstrated that the Wellington Region has significant streams
and rivers that support trout fisheries and trout spawning( FAO ,2015). Specifically, the
Ruamahanga and Hutt rivers were found to contain a large number of anglers in all years(Trout
aquaculture ,2018). The rivers also have many tributaries like Waihoinie River that had a great
reputation in providing an adequate aquatic ecosystem for spawning of rainbow trout (Trout
aquaculture, 2018). Other than that, the whole of New Zealand has significant large water bodies
than land which provide great environments with streams, rivers, and tributaries that allow
Rainbow trout survive and spawn(Fish and Game Organization ,2018).
Recourses Needed
A consistent water supply is needed in Rainbow trout farming. The replacement of water
should be continuous to allow only fresh, clean and oxygen-rich water remains in the
fisheries(Tower, 2012). The quantity of eggs per unit is primarily determined by the amount of
fresh water a unit can hold. The frequency of water exchange varies depending on where the fish
are grown( FAO ,2015). Water supply in earth ponds should be exchanged in about 5 to 5 times a

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day but typically it is exchanged twice a day(Berrill, MacIntyre, Noble, Kankainen & Turnbull,
2012). There various production options required depending on the type of farming one is
desiring to do(Tower, 2012). This includes the eyed egg production, fry production fingering
production, and table fish production.
Various production devices are required in rainbow trout farming. This includes hatching
trays, polypropylene or fiberglass rearing trough and tanks, membrane tanks, lined and unlined
tanks and concrete tanks may be used in all types of productions(Tower, 2012). Earth ponds have
been used for a long duration though lately, most farmers do not prefer them (Ministry for
Environment 2018). Water supply and drainage should be well constructed in earth ponds
allowing inlets and outlets plus deep ends and shallow ends. Mechanical and biological filters are
other crucial requirements for Rainbow trout farming in order to avoid environmental
pollution(Tower, 2012). During the site selection, the basics of selection should primarily depend
on the availability of water supply including both the quality and quantity of available water as
well as the suitability of the site. A rule of thumbs by Edwards in 1989 suggest that per every
tonne of rainbow trouts produce, water should run at a rate of ten liters per second. Human
resource, especially in management and planning, is also essential in starting a new production
unit(Berrill, MacIntyre, Noble, Kankainen & Turnbull, 2012). There are various stems involve
in planning which includes knowing the existence of capital needed and available markets,
elaboration of engineering design, acquisition of permission, construction, and a trial run(Tower,
2012). For proper growth and development of rainbow trouts high protein feeds is usually the
first line of desired feed.
Potential Risks and Mitigation

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Currently, in New Zealand, rainbow fish are prohibited to farm, therefore, government
interventions need to be addressed. The demand and automatic feeders are usually released when
the fish has an appetite( FAO ,2015). However, rainbow fish are usually greedy which may read
unnecessary feeding thus high cost of feed may be one of the major problems during farming.
Poor feeding, on the other hand, may lead to feeding problems that make larger rainbow fish bite
or eat the smaller fish therefore there will be poor production. Other than that, Rainbow trout
should be grown in areas which are not prone to predators such as crocodiles and snakes or other
larger fish like sharks. Other than that, there are a variety of diseases and parasites that can affect
the rainbow trout in any production unit(PAEK & PARK, 2016). Such diseases include
Furunculosis, bacterial kidney disease, vibrosis, bacterial gill disease, infective pancreatic
necrosis and viral haemorrhage septicaemia . Some of the parasites that attack the trout include
white spots, fluke, trematode parasite and hexamiatatic ostomies. Most of them especially the
parasites have no treatment available thus their effects can be vast. Construction of production
units need technical know-how and education hence it can be expensive in terms of human
resources and materials of construction.
Potential Markets and revenue
There are very strong markets for rainbow trout that exist across Europe and the USA, where
only in Chile, USA and Norway have a significant amount of rainbow fish
produced( FAO ,2015). The trout prices have demonstrated an increase over the
years(Waynarivich, 2015). For example in Norway, between the 2012 and 2013, there was a
significant increase in the prices by 10%. Their first sale exports ranged around NZ$9.50/ kg.
This is a good indication that rainbow trout have a possible international market(Waynarivich,
2015). A projection done by European Maritime and Fisheries Fund(EMFF) showed that about

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158 million tones of fish were produced worldwide by the year 2015. However, the demand has
been increasing day by day due to change in lifestyles as affected by most chronic diseases and
from medical advice(Settera, 2016). The change is expected to change over the time with an
increase of about 35% by the year 2022(Hayes, 2013). This creates a potential market for the
Rainbow trout(Waynarivich, 2015). A debate by federal farmers and Sanford limited in the year
2012 concerning rainbow trout showed that New Zealand is missing out hundreds of millions of
dollars in export due to the banishment of rainbow trout(Settera, 2016). Other works in branding
techniques need to be addressed. Freeze branding of young trout has demonstrated to be
effective(PAEK & PARK, 2016).
Cost-benefit analysis
The initial cost of rainbow trout farming is quite expensive ( FAO ,2015). This is due to
various construction and purchase of assets and liabilities(PAEK & PARK, 2016). Expensive
facilities are generally needed for example construction of concrete ponds. The frequent years,
the cost is minimized with an increase in production. This makes the benefits to outweigh the
cost(Settera, 2016). However, a study that was done in Nepal showed that the cost varies
depending on the amount of production. The result showed that per every NRs255 used in the
production of one kilogram a sale of NRs 300 was archived(Hayes, 2013). New Zealand target a
net profit of one billion dollars in all aquatic fish. This can only be archived only if the
government reinforce and support trout farmers(Settera, 2016).
References

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Berrill, I., MacIntyre, C., Noble, C., Kankainen, M., & Turnbull, J. (2012). BIO-ECONOMIC
COSTS AND BENEFITS OF USING TRIPLOID RAINBOW TROUT IN
AQUACULTURE: REDUCED MORTALITY. Aquaculture Economics &
Management, 16(4), 365-383.
FAO (2015) Fisheries & Aquaculture National Aquaculture Sector Overview (NASO)..
Retrieved from http://www.fao.org/fishery/countrysector/naso_newzealand/en
Fish and Game Organization (2018) Rainbow Trout | Fish & Game New Zealand. . Retrieved
from https://fishandgame.org.nz/freshwater-fishing-in-new-zealand/nz-fish-
species/rainbow-trout/
Hayes, J. (2013). Recommended biological and water quality limits for trout fishery and trout
spawning waters in the Wellington RegionAqua. Aquanet Consulting Limited, 3(50), 20-
50.
Heather, B. (2012). Trout farming back on table. Retrieved from
http://www.stuff.co.nz/business/industries/3232447/Trout-farming-back-on-table
IBAAF , (2018) New Zealand species suitable for aquaculture. » Land Based Aquaculture
Assessment Framework. . Retrieved from http://www.lbaaf.co.nz/nz-aquaculture-species/
Ministry for Environment (2018) Appendix 1: The aquaculture industry in New Zealand |
Ministry for the Environment. Retrieved from
http://www.mfe.govt.nz/publications/marine/aquaculture-risk-management-
options/appendix-1-aquaculture-industry-new-zealand
Omaima Harun, N., Zou, J., Zhang, Y., Nie, P., & Secombes, C. (2014). The biological effects of
rainbow trout (Oncorhynchus mykiss) recombinant interleukin-8. Developmental &
Comparative Immunology, 32(6), 673-681.

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PAEK, J., & PARK, K. (2016). An Economic Analysis of Rainbow Trout(Onchorhynchus
mykiss) Aquaculture Farms. Journal Of Fisheries And Marine Sciences Education, 28(5),
1280-1289.
Parol, J., Pietrzak-Fiecko, R., & Smoczynski, S. (2014). Polycyclic aromatic
Hydrocarbons (pahs) in smoked rainbow trout ( oncorhynchus
mykiss). Zywnosc.Nauka.Technologia.Jakosc/Food.Science.Technology.Quality.
Settera, J. (2016). Fish market Review 2015. Natural Resources Institute Finland, 1, 5-10.
Tower, L. (2012). How to Farm Rainbow Trout. Retrieved from
https://thefishsite.com/articles/cultured-aquaculture-species-rainbow-trout
Trout aquaculture (2018) Land Based Aquaculture Assessment Framework. . Retrieved from
http://www.lbaaf.co.nz/nz-aquaculture-species/modelled-species/trout/
Waynarivich, A. (2015). Small-scale rainbow trout farming. FAO, 561(2070), 50-89.