Ag tech "isn't a ... fictitious dream"
Reducing emissions on the farm without reducing the amount of milk or meat produced is enormously complicated - an intricate interplay between animals, the weather and climate, and inputs like fertilisers.
Dr Harry Clark, who runs the government-funded Agricultural Greenhouse Gas Research Centre, said while there were some big challenges, dismissing technological solutions was unfair.
"It isn't a sort of fictitious dream that they're peddling. There are technologies going to come along that are going to certainly help address the issue of agricultural greenhouse gases."
Clark said the biggest breakthrough in three decades had been in developing a feed that reduced animal methane emissions by a third.
It has regulatory approval in the EU and elsewhere, and Clark said it could start to be available in Aotearoa in two years.
But a major hurdle that will push out the timeframe is that, unlike overseas where many animals are kept and fed indoors, New Zealand animals graze over large areas outdoors - making it very difficult to get the inhibitors into animals' stomachs.
Dairy cows do come in twice a day for milking, where they can be fed the substance, but it is likely to be less good at reducing emissions, which makes it less cost-effective to develop or use.
Other options likely available in the second half of the decade are improvements in selectively breeding low emissions animals, which could add up to 10 per cent reductions over 10 years or so, as well as feed additives like seaweed.
And there are new generation nitrous oxide inhibitors that can be put directly on urine patches left by animals coming online within five years.
But Clare said the real game-changer was a potential methane vaccine, which showed real promise but would likely not be available until the middle of the next decade.
"It is suitable for every animal in every kind of system, and there is no other technology you can say that about, so that's why there's a lot of interest and a lot of potential investment."
But Clark said the industry was not relying on technology to fix everything.
Over time things like pricing emissions, new environment rules, better practices, and incentives to plant trees would change how land was used.
Farmers on board with changes but some targets "just madness"
The primary sector group He Waka Eke Noa said its proposal met the target of a 10 per cent reduction in methane by 2030.
New Zealand's goal is to eventually cut pollution by between 24 to 47 per cent by 2050.
Fourth-generation deep south sheep farmer Leon Black said the industry could get to 20 per cent over time without radically reducing output, but the halving would never happen.
"Some of the targets they're putting out there, in theory at the moment, are just madness.
"Because the chances that you could possibly achieve [them] without just destroying an industry are pretty, pretty slim.
"If you put something out there, which was completely unfeasible ... [then] no one's going to buy into it.
"And it's going to be ... soul-destroying for those of us that have actually put a lot of money and time into it."
Clark agreed that hitting the upper range of the target would be very challenging and would require some technological breakthrough.
Black has been working hard on selective breeding and selling lower methane animals.
He said most farmers were on board for the changes.
But he said they already felt pummelled by new environment and health and safety standards, on top of Covid-19 labour shortages, and were struggling to cope.
"You only want to have so many challenges. If you are playing a rugby team you would prefer it's not stacked with All Blacks when you turn up to the Saturday game.
"It seems like we're being beaten up on from a great height by some much bigger dudes, and ... in my view [it's] not always justified.
"They just haven't actually let us play the ball in the right direction."
Government funding boost timely, industry says
The government last month announced $339 million over four years to tackle the emissions problem.
Clark said the scale of the investment was about right to start tackling the scope of challenges, but further investment would be needed.
Pastoral Greenhouse Gas Research Consortium was set up in 2003 and has since spent nearly $100m of industry and government money on researching ways to reduce pollution.
General manager, Mark Aspin, said the groundwork had been laid and the Government's new injection of money came at a really good time.
But he was realistic about the challenges ahead - any tech must be practical and easy to use by farmers, and it was still not known how much it would cost.
A new research and development plan is being drawn up by the Government and industry and is expected this year.
- RNZ
