A startling sight greeted an official from the Norwegian Nature Inspectorate who was on a routine inspection of a remote area of Telemark county in Norway last Friday: A large herd of reindeer lying dead close together on the ground.
323 animals—70 of them calves—were confirmed to be dead, apparently victims of a powerful lightning storm, although that is yet to be fully confirmed.
“We sent up a team of eight people to take samples to be sent to the Norwegian Veterinary Institute for research. Then we will know for sure how the animals died,” NNI spokesman Knut Nylend told The Local.
“We’ve heard about animals being struck by lightning and killed, but I don’t remember hearing about lightning killing animals on this scale before. We don’t know if it was one or more lighting strike; that would only be speculation,” Nylend added.
But is it even possible for so many reindeer to be killed by lightning all at once?
In short, yes. Herds of cows (although usually not 300 of them) have been killed by lightning before, and reportedly more than 650 sheep were killed by lightning in Utah in 1918. Such deaths are likely related to a common reaction to storms by various herd animals: Huddling.
“They were lying there dead in a fairly concentrated area. Reindeer are pack animals and are often close together. During a heavy thunderstorm, they may have gathered even closer together out of fear,” said Nylend.
As to the mechanics of it, it has very little to do with a direct hit by lightning and probably a lot more to do with ground current.
“When animals or people are in groups, most are being killed by the ground current,” John Jensenius, a lightning safety expert from the National Oceanic and Atmospheric Administration (NOAA), told The Verge. “First, there’s a direct strike — this is what most people think of when they think of lightning — that hits the tree or maybe the ground nearby. The energy then spreads along the ground surface, and if you’re anywhere near that lightning strike, you absorb it and get shocked.
“Lightning goes up one leg and down another. Animals are more vulnerable because their legs are spread out more, so the ground currents travel more easily in their bodies. It doesn’t matter if they’re touching, or exactly how close they are, it matters that they were all in the area hit by lightning. Ground currents are the thing that’s responsible for the most lightning deaths and injuries in both people and animals.”
Ground current can spread quite far—in this case, perhaps 80 feet in diameter—and when it strikes a living creature, it travels through the body to the heart, which usually stops. In humans, this can often be treated with CPR—but obviously, reindeer aren’t quite so lucky.
Image credit: Håvard Kjøntvedt