prospect. Once production becomes more routine and operating under standard
procedures, it is believed that companies will direct greater focus towards
improving efficiency in a similar way the inshore longline system developed in New
Zealand in the 80s and 90s. In further support of the open ocean mussel farm
mentioned in the case study, mussel spat is being caught in commercial numbers as
far as 12 km off the coast and may be accessible even further out to sea. This means
the whole production chain can be handled on the same farm. It is estimated that
this particular farm will deploy 350–400 km of mussel production rope per annum
within the next 3–4 years. Once this farm has shown itself to be technically and
economically viable, other farm owners have indicated that they will start production. The potential will then be enormous.
There are some considerations regarding production and seasonality that must be
taken into account. It has been found that mussels inshore have a longer and more
varied condition window than mussels grown offshore (Heasman, unpublished), i.e.
shellfish conditioning at the open ocean site is more uniform across the growing
area and is shorter in duration. This is an advantage in terms of processing however
the shorter window leads to production peaks and troughs. For example, an offshore
farm may be capable of producing 30,000 ton of mussels but if they all have to be
harvested in a 6–12 week period it will require a large number of vessels and
processing capability for that period. These units will sit idle or at low usage for the
remainder of the year. For this reason it is important to have multiple species in
production simultaneously, unless a species that can be harvested year round is
utilized.
Despite the findings in New Hampshire, other open ocean locations and technologies may be more suitable for offshore farming. An example of this is Ocean
Blue located 11 km offshore Panama. Here they are raising Cobia (Rachycentron
canadum), a fast growing warm water species, in 6000 m
3 Sea Station™ cages.
Last year they produced 400 MT with an expected 1200 MT by 2014. Currently
they feed via day boats through pneumatic blowers into each cage. Commercial
feed barges (http://www.akvagroup.com/products/cage-farming-aquaculture/feedbarges/ac-450-panorama) are available however they cannot withstand seas over 4.
5 m. These barges are common in protected water ways in Norway, Chile and
Canada. Certainly if aquaculture is to move further from shore, remote feeding
systems will need to be improved to withstand seas >10 m. Also important will be
real time monitoring of fish behavior and environmental parameters inside and
outside the cages. In this, farmers can best manage animal welfare to optimize
growth and condition.
Ocean farming will slowly creep offshore as new, economical and robust
technologies develop. Farms of the future must be turnkey allowing for remote
operations such as feeding, environmental monitoring, fish health and harvesting of
product. These platforms could ultimately produce their own energy through wave,
wind and tidal turbine technologies. Ultimately, farming centers should be located
close to large coastal populations to reduce the carbon footprint from exporting
overseas.
3 Technological Approaches to Longline- and Cage-Based …
91
procedures, it is believed that companies will direct greater focus towards
improving efficiency in a similar way the inshore longline system developed in New
Zealand in the 80s and 90s. In further support of the open ocean mussel farm
mentioned in the case study, mussel spat is being caught in commercial numbers as
far as 12 km off the coast and may be accessible even further out to sea. This means
the whole production chain can be handled on the same farm. It is estimated that
this particular farm will deploy 350–400 km of mussel production rope per annum
within the next 3–4 years. Once this farm has shown itself to be technically and
economically viable, other farm owners have indicated that they will start production. The potential will then be enormous.
There are some considerations regarding production and seasonality that must be
taken into account. It has been found that mussels inshore have a longer and more
varied condition window than mussels grown offshore (Heasman, unpublished), i.e.
shellfish conditioning at the open ocean site is more uniform across the growing
area and is shorter in duration. This is an advantage in terms of processing however
the shorter window leads to production peaks and troughs. For example, an offshore
farm may be capable of producing 30,000 ton of mussels but if they all have to be
harvested in a 6–12 week period it will require a large number of vessels and
processing capability for that period. These units will sit idle or at low usage for the
remainder of the year. For this reason it is important to have multiple species in
production simultaneously, unless a species that can be harvested year round is
utilized.
Despite the findings in New Hampshire, other open ocean locations and technologies may be more suitable for offshore farming. An example of this is Ocean
Blue located 11 km offshore Panama. Here they are raising Cobia (Rachycentron
canadum), a fast growing warm water species, in 6000 m
3 Sea Station™ cages.
Last year they produced 400 MT with an expected 1200 MT by 2014. Currently
they feed via day boats through pneumatic blowers into each cage. Commercial
feed barges (http://www.akvagroup.com/products/cage-farming-aquaculture/feedbarges/ac-450-panorama) are available however they cannot withstand seas over 4.
5 m. These barges are common in protected water ways in Norway, Chile and
Canada. Certainly if aquaculture is to move further from shore, remote feeding
systems will need to be improved to withstand seas >10 m. Also important will be
real time monitoring of fish behavior and environmental parameters inside and
outside the cages. In this, farmers can best manage animal welfare to optimize
growth and condition.
Ocean farming will slowly creep offshore as new, economical and robust
technologies develop. Farms of the future must be turnkey allowing for remote
operations such as feeding, environmental monitoring, fish health and harvesting of
product. These platforms could ultimately produce their own energy through wave,
wind and tidal turbine technologies. Ultimately, farming centers should be located
close to large coastal populations to reduce the carbon footprint from exporting
overseas.
3 Technological Approaches to Longline- and Cage-Based …
91