Re-starting Aquaculture –Return to Chaos?
Thu, 21 Jan 2010 1:38 pm – Posted by Mandy | 6 Comments
Blogger: North Island Conservation Manager Mark Bellingham
As an island nation surrounded by sea, we’re in a prime position to take advantage of one of the world’s fastest growing industries: aquaculture.
Commercial aquaculture in New Zealand started in the 1960s, and since then it has grown to an industry that brings in $360 million dollars a year.
By loosening up our laws and giving the industry a cash-injection, National is hoping to build it into an industry that brings in around 1 billion dollars each year by 2025.
At present, Green shell mussel, King salmon and Pacific Oysters farms are dotted around the country from Northland to Southland taking up 0.02% of our coastline.
Aquaculture Farm Facts, source: Aquaculture New Zealand
Attempts to kick-start the industry in the 1990s under National were unsuccessful because it relaxed controls on aquaculture so much that large speculative proposals (some were up to 10,000 ha) emerged – outraging fishers, boaties and the public alike.
A Resource Management Act clampdown ensued, in effect stopping any aquaculture development.
In order to shake-up the industry and recommend changes that will allow this industry to thrive, an advisory group was appointed in 2009.
The advisory group’s report has made some useful suggestions, but it needs to build on the work by Aquaculture NZ and Forest & Bird to identify appropriate places for aquaculture in Northland and the Firth of Thames.
Key issues that still need addressing are:
• Identifying those areas that are closed to aquaculture are crucial.
- This is needed to ensure the protection of migration routes for our marine mammals. There are been plenty of examples of orca and whales getting caught in the ropes of offshore marine farms.
- Sites with outstanding landscape values should remain no-go zones.
• Creating a fair process for communities, environmental groups and coastal users.
On top of this Gerry Brownlee has allocated two rounds ($600,000 and $500,000) of funds to businesses wanting to start-up aquaculture operations in New Zealand.
This funding will not only kick-start the industry, but it will also allows businesses to develop better-funded proposals that address the concerns of recreational, environmental and community groups.
Increasing the productivity of our seas without over-fishing our marine life is a move in the right direction.
And stimulating this industry has other fringe environmental benefits, such as creating a push to clean up discharges and pollutants, and protecting these areas from destructive fishing practises such as bottom-trawling.
We just need to make sure these law changes are done in consultation with those who use and care about these waters, so marine farms are managed in a sustainable and environmentally friendly manner.
Fast-tracking the law and bypassing these processes will no doubt return us to the chaos of the 1990s.
For more information on aquaculture in New Zealand see – www.aquaculture.org.nz
I heard that concentrated populations of salmon cause a huge amount of damage to the sea-floor - is that true? What are some of the other considerations that we need to take into account with respect to some of these other types of farming (i.e Pacific Oysters etc)?
Here’s some of the concerns about salmon farming:
Fish wastes and uneaten feed smother the seafloor beneath these farms, generating bacteria that consume oxygen vital to shellfish and other bottom-dwelling sea creatures.
Disease and parasites, which would normally exist in relatively low levels in fish scattered around the oceans, can run rampant in densely packed fish farms. Pesticides fed to the fish and toxic copper sulfate used to keep nets free of algae are building up in seafloor sediments. Antibiotics have created resistant strains of disease that infect wild and domesticated fish.
Just had a natter with our aquaculture guru - Mark - and he says that salmon farming practises have improved significantly since the 1980s.
Apparently salmon farming around at Big Glory Bay at Stewart Is had problems in the late 1980s with waste. Salmon farming increased the nitrogen concentration of the bay by about 30%. At the same time there were a series of algal blooms, that killed caged salmon and wild fish alike. This forced the salmon farming industry to improve their farm management and monitoring.
Recent practice has seen :
• a marked reduction in waste food with automated feeding systems
• farms (or sea-cages) being sited in areas with more tidal flow so as to disperse wastes from excess food and fish,
• sea-cages being shifted around to lessen the effects on the sea floor organisms.
NZ farmed salmon are not fed pesticides or antibiotics, although this occurs in some other countries, and diseases here are managed through lower stocking rates and cleaner water conditions.
Hope that answers your question Karen!
Aquaculture… marine farming to myself as i see it is a positive look into our future as a sustainability in the right direction. Namely marine fish farming eg butterfish or so known as greenbone.. if we took a positive aproach to marine farming with species of fish stock like butterfish we would take the pressure of wild caught stock….we would truly have an eco system that would be sustainability relyable….Aquaculture marine farming is a new positive look for all our future…..
Great - thanks so much for the info Mandy! I’ve just moved back from the UK and am trying to get an understanding of salmon farming practices back here… I know in some countries farmed salmon are feed dye to enhance the pink colour of the fish. Is this something that happens in NZ? Also, do you know what farmed salmon in NZ are fed?
Thanks
Generally our salmon is fed dried fishmeal - anchovies, pilchards and other fish by-products and is recombined with fish oil before feeding. And no, they’re not dyed. Here’s some more information here -
http://www.listener.co.nz/issue/3627/columnists/14384/go_fish.html