Why these massive wasp 'super nests' are popping up in Alabama

Most people probably wouldn't look at a two-metre long hanging wasp nest and call it beautiful, but that's how entomologist Charles Ray sees it.

Ray is looking into reports of at least 19 of these so-called "super nests" in Alabama, a phenomenon scientists believe is linked to warming weather.

Usually, the state's wasp nests are built on the ground and are about the size of a volleyball, housing 4,000 to 5,000 wasps. But the super nests — or perennial yellow jacket nests — can get big as a Volkswagen Beetle and contain upwards of 15,000 of the stinging creatures.

"It's very beautiful. It has texture and colour and then the yellow jackets all over it," Ray, a researcher at the Alabama Co-operative Extension System (ACES), told As It Happens guest host Susan Bonner. 

"You almost feel the energy around these nests. There are wasps working on the paper, there are wasps flying in and out with prey. You say busy as a bee? Well, this is busy as a wasp. They are incredible as far as the energy they have."

Warm-weather wasps

The super-nests aren't a new phenomenon in the state, Ray said. Scientists first noticed them popping up after a particularly warm winter in 2006, he said, when a total of 90 were counted.

Since then, maybe one or two show up each summer. But 2019 could be on track to be another breakout year, Ray says.

He's personally inspected four super nests this summer, and is working to confirm another 15 other reported sightings.

Their appearance, he says, is likely connected to warming weather. 

Usually, wasps either freeze to death in the winter or starve due to a lack of available food. But if the winter doesn't get cold enough, the wasp colonies survive.

"And the other thing that's happening is rather than having a single queen start the spring with maybe a thousand or 4,000 workers that made it through the winter, they all start with 35 to 150 queens and each one of those queens can produce, over her lifetime, 20,000 eggs," he said.

That means the nests grow fast.

"When they have this many workers, those nests can literally double in size every two weeks," Ray said. 

They can be dangerous

One person who might not find the wasps as captivating as Ray does is James Barron. He told the New York Times that he was stung 11 times when he tried to spray down the super nest that grew on his smokehouse.

Ray has personally inspected the 2.1-metre long nest visible hanging from Barron's smokehouse roof, and says there's probably even more nest growing inside the wall. 

Yellow jackets can be particularly aggressive compared to other stinging insects, and are believed to be responsible for almost all of the stinging deaths in the United States, Xing Ping Hu, another Alabama Extension entomologist, wrote in a press release in June. 

"They're worrying me, because a child wouldn't have a chance out there," Barron said. "I have many grandkids. A child couldn't run fast enough, and I'm worried about that."

Just leave them be, says Ray 

But Ray says everyone who's been injured by wasps from super nest have tried to tear down the nests themselves.

"These nests are actually not very dangerous unless you disturb them," he said.

Unlike the ground nests, which kick into self-defence mode whenever someone approaches, these wasps don't seem to be bothered by having people around. 

Ray says he conducted a 15-minute TV interview underneath one, and didn't get stung once. 

"My advice is if you can leave it alone they will not bother you," he said. "The large nests are surprisingly docile, and I'll use that word, because they don't seem to care if you're there or not."

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If you can stomach the nest for the summer, Ray says it will most likely die when winter comes around.

And if you can't wait that long?

"If you cannot, you really need to engage the services of a professional exterminator," Ray said. "This is not something for the average homeowner."

Written by Sheena Goodyear. Interview with Charles Ray produced by Jeanne Armstrong.