That French deer isn’t the only animal getting 'drunk' on nature

The deer spins in circles in an otherwise empty field in rural France, increasingly erratic until it flops onto the ground. Could these antics possibly be the result of … intoxication?

That's what local police suspected when they first saw the video. This week, the Gendarmerie de Saône-et-Loire posted an online warning to locals to watch out while they're driving for unpredictable behavior from wild animals that may have consumed fermented fruits or other plants.

It's impossible to know for sure whether the deer's behavior is actually a sign of intoxication—or perhaps a sign of injury, disease, or neurological disorder, the law enforcement agency noted. But inebriation is not as unusual as you might think in the animal kingdom.

In fact, several wild animals are known to get buzzed off of nature, from poppies to hallucinogenic mushrooms to the grapes that, when fermented, become alcohol. Although it's mostly thought to be by mistake, researchers suspect chimpanzees may even be seeking out their equivalent of two alcoholic drinks a day.

From elephants to reindeer, here are a few intriguing examples.

Cedar waxwings gorge on berries

Known for their striking plumage, which includes a large crest and a black eye mask, this North American species is unusual among birds for its ability to eat only fruit for several months. Fruit can be a great source of energy, but overripe fruits and berries can pose an invisible threat to the birds.

Naturally occurring yeast begins to ferment the ripe fruit, converting sugar molecules into ethanol and carbon dioxide. If the fruit hasn’t begun to rot, it’s technically safe to eat, but it can potentially make the birds drunk.

(These wasps tolerate high amounts of alcohol—without getting a hangover.)

Like humans, inebriated waxwings display slower reflexes and impaired decision-making, which can make the birds more likely to succumb to predators, vehicles, or window strikes.

“Alcohol is a neurodepressant, so it turns down the nervous system and those quick reflexes. Everything that you would imagine happens when a person is drunk, it happens to animals, too,” says Sara Wyckoff, wildlife veterinarian for the Texas Parks and Wildlife Department.

A 2020 study led by Piotr Tryjanowski, a zoologist from the Poznań University of Life Sciences in Poland, analyzed scientific papers and YouTube videos, which documented 55 species of birds that drink alcohol—including semi-wild animals or pets. Many of the video clips featured parrots, corvids, and other stereotypically ‘intelligent’ bird species sipping from human beverages.

“Why do they do it? Probably for the same reason we go to bars,” Tryjanowski says.

African elephants get drunk on fruit

Reports of African elephants becoming intoxicated after eating fermented fruit from the marula tree fill both the popular and scientific literature. Some scientists have questioned the validity of these reports, citing the elephants’ large size and the vast quantities of alcohol they would require to get drunk.

As a graduate student at Canada’s University of Calgary, Mareike Janiak studied how different species metabolize ethanol. Janiak’s 2020 study in Biology Letters found a huge genetic variation in various species process alcohol dehydrogenase, the main enzyme involved in breaking down ethanol.

(Bats and agaves make tequila possible—and they're both at risk.)

Perhaps not surprisingly, given our love affair with alcohol, humans are very efficient at breaking down ethanol, which makes it harder for us to get drunk than, say, horses, cows, and pigs. Janiak found that many fruit-eating species can detoxify ethanol very well, perhaps owing to the naturally occurring ethanol in overripe fruit.

African elephants, however, have a genetic mutation that makes it harder to metabolize alcohol dehydrogenase, suggesting the giant animals can get drunk from marula fruit, Janiak says. Yet they’re likely not pleasure-seeking, she adds—just hungry.

“Ethanol production happens when there is sugar, and sugar is energy,” Janiak says. “Being able to digest the ethanol might allow you to eat more of the fruit that's technically rotten or bad.”

Reindeer munch on hallucinogenic mushrooms

In Siberia, reindeer—the animal North Americans call caribou—share habitat with the hallucinogenic mushroom Amanita muscaria, or fly agaric. The fungus, also called the “Christmas mushroom” due to its red cap and white spots, is also a favorite of Siberian shamans, who take it as an “inebriant and a hallucinogen,” according to a 2018 study.

Biologists have documented reindeer eating the poisonous yet nutritious mushroom, whose toxins are neutralized by their complex stomachs.

It’s not clear whether ingesting the fungus causes the ungulates to experience nausea, vomiting, and disorientation as it does in humans.

Tree shrews prefer boozy nectar

In Thailand, Malaysia, and Borneo, seven tree shrew species feed primarily on nectar from bertam palms. The trees’ nectar rapidly ferments, becoming a boozy, sweet syrup of over three percent alcohol.

Unlike cedar waxwings, the tree shrews seem to suffer no ill effects from this steady, high-alcohol diet, according to a 2008 study, nor do the animals show any apparent signs of intoxication.

In 2020, researchers found that other species of bertam pollinators, including squirrels and other rodents, are adapted to consuming high amounts of alcohol.

While animals could imbibe plants for fun, Tryjanowski believes that it’s the underlying nutritional value that’s most important to them.

“Consuming these foods can give you sugar and vitamins—as well as alcohol,” he says.