Ocean Action Hub

1 March 2017 - One of the aims of NIWA [New Zealand's National Institute of Water and Atmospheric Research] setting up a $50 million marine science centre at Ruakaka was to look into incorporating yellowtail kingfish into the aquaculture industry. 

But the skills NIWA staff have picked up along the way in breeding the ocean going (pelagic) fish are coming in handy as the world grapples with the effects of warming oceans and rising acidification.

Professor Phil Munday, New Zealander Dr Bridie Allan and five other team members from James Cook University in Queensland have just spent five weeks working with NIWA staff looking at the impact of increased COlevels on kingfish.

"Very little is known about the effect on larger pelagic species, which could be highly susceptible, but are actually very difficult to work with," Professor Phil Munday says,

"They're very hard to culture – not many places in the world are able to culture them, but the NIWA team have the expertise," he says.  "We are working with yellowtail kingfish larvae in big tanks, replicating the warmer and more acidified conditions expected at the end of the century"

 "We couldn't do this in Australia to this standard," 

It's the first trial of its kind at Bream Bay, and NIWA Assistant Regional Manager Michael Bruce says he's keen to attract more of this work.

"We want to raise the profile of our capability and the way we work with outside groups."

As the oceans warm and increasing atmospheric carbon dioxide is absorbed into sea water the effects on sea life is still largely unknown.

Ocean pH is currently 8.1 down from 8.2 in pre-industrial days. But by the end 2100 its expected to fall to less than 7.9.

Shellfish have come under the spotlight, with most fish research done on cod and reef fish. This shows the larvae of some fish species are affected by low pH affecting growth, metabolism and behaviour. They can lose their sense of direction, be more reckless and lose their sense of risk aversion around predators.

Breeding from families within species that are less vulnerable to the effects of acidification is one avenue being looked at.

"There appears to be enough genetic diversity in the NIWA kingfish brood stock to be able to test for heritability," Munday says. "We can look at whether some family lines are more resilient, and if they have the capacity to adapt." CONTINUE READING: http://www.stuff.co.nz/business/farming/89899039/will-big-ocean-fish-cope-in-a-warming-world

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Publication date: 
Publication Organisation: 
New Zealand Farmer
Publication Author: 
Delwyn Dickey
Thematic Area: 
Sustainable fisheries
New Zealand