A history of New Zealand's wildfires - and what's to come

Off the back of two devastating wildfires in Tongariro National Park, the country is facing another summer of increased fire risk. And while our wildfire history pales in comparison to our neighbours in Australia, New Zealand has had its share of raging hillside infurnos. Our reporter Kate Green takes a look back at some of the big ones, and a look forward at future risk.

It's early February, 1946, and a long drought has left Taupō hot, and dry.

On one unassuming roadside, a dropped cigarette butt is about to light a fire that burns for days, fanned by a strong northerly wind, through more than 100,000 hectares of land, including 12,000 of pine forest.

"Where it is strongest, little can be done," proclaimed one Newsreel special, which came out on 10 February. "Only rain can end it."

The blaze was extinguished in due course - although little information is available online about how this was done.

After destruction comes new life. Come autumn, an unexpected surge of life was observed when radiata pine sprung up in dense patches over burnt plantations; the fire had opened cones which were normally closed and liberated the seeds.

Victoria University ecologist Nicola Day said fire could often have unexpected or unseen effects, particularly for the soil below the fireground.

Her work has involved analysing firegrounds in Canada, and more recently, the sites of wildfires at Lake Pukaki and Lake Ōhau in 2020.

Historically, Aotearoa had experienced a low fire-risk and its plants hadn't evolved to survive them - but Day said they'd found a number of natives were hardier than they looked.

"If you go into a site like that it looks like everything's dead," she said. "But actually, the top of the plants have burnt off and died, but the inside of them, the part that controls the growth of them, has survived."

Woody species were the slowest to recover, she said, but even they could regenerate and look alive again within a year or two.

But in the meantime, it left a gap for exotic species - which tended to grow much faster than native species - to take over, making it even harder for natives to repopulate.

It happened at Lake Ōhau in 2020. The fire was lit by an electrical short circuit on a power pole, and it raged for nine days, destroying 48 homes and buildings and damaging 5043 hectares of land, making it one of New Zealand's most significant wildfires in recent history.

Day said it took the landscape a couple of months to look green again, and for a while, the main species were exotic. But given another couple of years, nearly all the same species had returned, albeit in different quantities.

Let's step back again in time: 25 November, 1955.

Over the next three days, a fire fanned by gale-force winds destroyed a third of the Balmoral State Forest in North Canterbury - 2400 hectares of timber.

News reports from the time described it as a "disastrous experience" for its owner, the Canterbury Forest Conservancy.

According to a booklet published by the New Zealand Forest Service in 2005 (The Balmoral Forest Fire of November 1955), the first signs of trouble came when residents heard "pistol-like cracks" and, "on investigation found the old mill burning fiercely" at about 10pm.

The only telephone nearby was in that very building, and very much on fire. So, one Mr Bailey drove six kilometres to the Forest Service headquarters to raise the alarm.

The booklet's author John Ward, who worked as a forest ranger and a rural fire mediator, mused on this question in its final pages: "Would we have done better in 2005? I think yes, and no."

"No amount of helicopters could have stopped that fire [in its early stages] but perhaps we could have made some real progress in aerial suppression when the wind dropped [on day three]. But would we have had enough men to patrol the Balmoral road and keep the main forest block safe?"

FENZ wildfire manager Tim Mitchell said while firefighting techniques had changed since those days, it still came down to "putting water on the red stuff".

Water was still the most effective way of dousing fire, but now there were additives available that could made it more effective at cooling or stopping its spread.

Aircraft had also become more powerful, he said, meaning they could carry more water more safely.

And a good thing, too - Mitchell said going by the data on large wildfires (that is, anything larger than 1000 hectares) the risk was increasing.

In the five decades from 1964 to 2015, there had been 19 such fires. In the past decade from 2015 to present day, there had already been 13.

"Still quite a reasonable number, but over a much smaller timeframe," Mitchell said. "On that basis, yes, you could say that certainly the trend is suggesting that the number of large wildfires is increasing."

It was likely caused by a number of factors, he said: warmer, dryer, windier conditions at times due to climate change, but also, "where we're living, and how we're living".

New developments meant towns were spreading outwards into rural areas with lots of vegetation and slopes which increased fire risk, and increased recreation ability meant people were accessing off-grid areas more often.

Farm and forestry equipment, too, was more powerful and ran hotter, making it more likely to cause a spark or ignite dry grass.

In fact, Mitchell said the data showed humans caused 98 percent of New Zealand's wildfires.

Hugh Wallace, team lead for fire and atmospheric sciences at the Bioeconomy Science Institute, said that fact was actually a bright spot for him - something we had the ability to change.

"Unlike North America, unlike Australia, we don't really get those lightning-caused fires. So basically, where you get more people, you get more fires."

Wallace said climate change was complicated, but some areas would definitely be in for more hot, dry, windy days, "which is the kind of conditions you do get fires on".

"My gut instinct is that we probably would get more big fires."

The Port Hills have seen two major events in the past decade - the first, in February 2017, was when two separate blazes burned through more than 1600 hectares, claimed the life of a helicopter pilot, nine homes and damaged five others, and took 66 days to extinguish.

The cause of one of the fires was deemed to be an electrical fault, and the other remains unknown.

Seven years later almost to the day, the first calls came in just after 2pm on Valentines Day in 2024.

At its peak, more than 130 firefighters, 15 helicopters and two aircraft fought the blaze, as it burnt about 470 hectares across the Port Hills in three weeks.

One home - a tiny house built out of a shipping container - was destroyed.

Stats NZ expects the risk of fire to increase in many parts of the country due to higher temperatures, stronger winds, and less rainfall associated with climate change.

Using data from the last census in 2023, Stats NZ said there were 4683 wildfires per year on average in the five years to 30 June 2022.

Fire and Emergency NZ said the 2019/2020 and 1998/1999 years remained the worst on record for number and area burnt, respectively.

Mitchell said better awareness was needed of how individuals could prevent fires - even things as simple as choosing not to mow the lawns or burn rubbish on a hot day, and pouring water on ashes after a bonfire.

"It's such an easy way to avoid a lot of the wildfires that we're having," he said.

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