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TENNANT CREEK, Australia — In a forgotten restaurant behind a gas station in this country’s red center, only metal and plastic remain intact. Chris Cook grabs a wooden door frame, which crumples like paper in his hand.
“It all collapsed,” says Cook, manager at Territory Pest Control in Australia’s Northern Territory. He looks at boards hanging in tatters from the ceiling. Thousands of uninvited guests have been busy since he last visited the abandoned building three years ago.
The destruction of the Galaxy Auditorium restaurant in Wycliffe Well — a tiny freeway stop that bills itself as the “UFO capital of Australia” — is the kind of destruction many places on the continent could face if Mastotermes darwiniensis can’t be stopped. These termites are the last survivors of an ancestral species that shared space with dinosaurs 150 million years ago. They are insatiable and unrelenting. And because of climate change, like their conspecifics, they are expanding their range.
A study conducted on six continents and published this fall in Science showed how much termites love a warming planet.
“The extreme response was really surprising,” said Amy Zanne, a professor of tropical ecology at the University of Miami and lead author of the study. She brought together more than 100 scientists to place logs in 133 locations around the world and then measured the speed at which they were eaten in different climates. “We ran the numbers over and over again,” she said.
Termites are crazy about heat, the study confirmed and quantified. With every 10-degree increase in temperature, their “wood find and consumption” increased almost sevenfold.
The Australian species is the most primitive of all termites and closest to the root of the evolutionary tree. Also called “mastos” or giant northern termites, they have a breeding superpower: almost any member of a colony can turn into the brood queen if the previous monarch is felled. Not only that, they have broad palates and have been known to eat lead, plastic, leather, ivory, and asphalt. Cook once treated a colony that got to the plumbing of a concrete building and climbed eight stories.
The species has long been an annoying part of life in tropical north Australia, the only place it was once found. But in the last two decades, it’s started to take hold farther south.
Cook spends his days driving thousands of miles through the often scorching Northern Territory. Tennant Creek — more than 10 hours from Darwin, the territory’s capital and closest city — is the small community where he’s testing whether the termites can be blocked, or at least baited out. The biggest concern is the impact they could have on the capital in Australia’s vast and isolated outback: Alice Springs, population 25,000, right in the line of their apparent advance.
“It’s a question of when, not if,” Cook said of the prospect. “They’re going to get here, and when they get here they’re going to cause a lot of trouble.”
Theo Evans, a biologist at the University of Western Australia who specializes in termites, said the giant northern termite first appeared about 20 years ago in the town of Ti Tree, 800 miles south of Darwin. It’s now a common pest there, eating through structures and gouging out local palm trees, a particularly popular meal.
But the pest control company has already been cleaning up damage for several hours south, including in the remote indigenous community of Papunya, who discovered their school had been attacked.
Extreme temperatures have so far protected the arid parts of Australia. In the country’s tropical zones, where the weather is reliably mild, there are numerous ravenous garrisons of the vast north. Like reptiles, termites do not generate their own body heat but absorb it from the environment. Even in the tropics, when the temperature drops below 68 degrees, “these termites can barely walk,” Evans said. “It’s pretty fun to see.”
However, frosty winter nights in Alice Springs are decreasing. Average temperatures have risen about 1 degree since 1910, and the number of days above 104 degrees per year has doubled since 1950.
Cook roamed Tennant Creek and inspected a cluster of buildings that form a tourist attraction indicative of the region’s gold mining past. He later placed the bait stations meant to attract termites, and each contained a new pesticide meant to kill the insects after they accidentally transported it back to their colonies.
No bait has yet proven effective against mastos. “If this product works … we’ll be ready when they reach Alice Springs,” he said.
Australia is far from the only place where termite diseases – and their extraordinary costs – are getting worse as the world gets hotter.
“People in Chicago who have very few problems with termites — not zero, but very few — could start getting the kinds of problems that people farther south would have,” Evans said. “And people in Toronto who basically don’t have any termite problems at all might get the kind of problems that Chicago has.”
Modeling in 2017 by Purdue University and the University of Lausanne concluded that 12 of the world’s 13 most invasive termite species could increase significantly in distribution by 2050 given current Earth temperature curves. The possible zones of incursion extend from Canada to Patagonia, from Finland to Iran, from New Zealand to Namibia – and even to Greenland.
Meanwhile, two species from Florida have revealed another potential threat as the species’ habitats begin to overlap: hybridization into new “highly destructive super termites.” Coptotermes formosanus and Coptotermes gestroi have shown a tendency to interbreed during warm winters, University of Florida scientists discovered in 2015. The young grow twice as fast as their parents.
Termites cause billions of dollars in damage worldwide every year. They also play an outstanding role in the carbon cycle.
“Basically, they’re like little cows, but instead of burping, they fart methane,” Zanne said. The guts of both creatures have become the perfect home for microbes that break down cellulose, part of the plant cell wall, into nutrients and dispose of methane gas as waste in the digestive process. About 20 million tons of methane are released into the soil or atmosphere from the rear ends of termites each year.
Still, she added: “If we didn’t have things like termites and microbes to break things down, we’d be walking on a pile of dead animals and plants. But what happens when you disrupt the system by doing things like warming the planet?
Alex Cheesman, a soil scientist at James Cook University who contributed to the Science study, said an increase in termite populations could create a worrying climate feedback loop.
“As a result of climate change, you get amplified climate change, and that’s why it’s really problematic,” he said. The hotter the world gets, the more termites can thrive. As more termites thrive, more methane can be released into the atmosphere. The more methane, the hotter the climate becomes.
Driving the six hours from Tennant Creek back to his base in Alice Springs on a scorchingly hot December morning, Cook seemed a little embarrassed as he discussed how greenhouse gases affect the pest control industry.
This year, South Australia faced an outbreak of the deadly tropical disease Japanese encephalitis for the first time in recorded history, as mosquitoes multiplied following floods scientists said were made worse by warmer air. In the United States, Lyme disease continues to spread as the ticks that transmit it move into new areas as temperatures rise. In the UK, destructive aphids feed on more plant species as the spring heat prompts them to lay eggs earlier.
“Climate change is really good for our industry,” Cook said despite his personal concerns for the planet. “There are more roaches, more mice, more of everything.”
