Advertisement

Boozed-up birds a risk during fall freeze period in Canada

image

[A waxwing feeds on rowan tree berries. GETTY IMAGES/Dan Kitwood]

It’s that time of year again.

The nights are growing cold. Trees are shedding their leaves. Birds are getting drunk and rowdy.

Depending on the thaw-freeze cycle, Yukon wildlife officials are bracing for inebriated Bohemian waxwings, says Meghan Larivee, laboratory co-ordinator for Environment Yukon.

“It is something that happens,” Larivee tells Yahoo Canada News.

These birds gorge themselves this time of year on the bright red berries of mountain ash and rowan trees in the territory.

Unfortunately, as the temperature starts to dip below zero at night and thaw during the day, the berries begin to convert starch to sugar. Yeast or bacteria get in, and when it warms up the fruit starts to ferment, producing ethanol.

A couple of years ago, the department was so beset by boozed-up birds that they had to set up mini drunk tanks.

“We know they’ve been eating berries because they’ve got red berries all over their beaks. And the other part is that they really do act similarly to anybody who is intoxicated — they don’t have co-ordinated movement and they seem kind of dopey and out of it,” Larivee says.

“They can’t fly straight.”’

It’s a phenomenon not unique to the Yukon. She says Ontario wildlife officials, too, have had to deal with drunk birds.

In Central America, wild bats often encounter fermenting fruit and nectar.

In a 2010 study, researchers at Western University fed wild-caught Central American bats either sugar water or ethanol and then released them to fly an obstacle course.

They found the bats had some tolerance to ethanol, likely because they regularly encounter fruit with concentrations of ethanol in the range of 0.6 to 4.5 per cent, according to the study published in the scientific journal PLOS One.

Five years ago, police were called after more than a dozen clearly injured young blackbirds were found dead at a primary school in Cumbria, England.

The Animal Health and Veterinary Laboratories Agency conducted toxicology tests that revealed at least one bird with a high level of alcohol.

One bird that had been found alive was sent to a wildlife rescue centre, where staff said it appeared “drunk” and unsteady on its feet.

“The bird had had to place its wings on the ground to steady itself, and had leant against the walls of its enclosure to keep upright, they said. After two days the bird fully recovered and was released back into the wild,” according to an article in the British Medical Journal.

And in 2011, photos of a drunk Swedish moose hung up in a tree after eating fermenting apples made headlines around the world.

[An intoxicated moose is discovered entangled in an apple tree by a stunned Swede in Goteborg, Sweden, on Sept. 6, 2011. THE ASSOCIATED PRESS/Per Johansson]

There have been reports of drunk elephants, though the sheer size of them makes some skeptical that they can possibly consume enough fermented fruit to affect their behaviour.

But parrots are known to imbibe and Malaysian pen-tailed tree shrews and the slow loris are well-known quaffers of the animal kingdom, according to another earlier study from Western University.

But despite imbibing at levels that would net an impaired charge, the tree shrews, too, show a preternaturally high tolerance for alcohol.

Bohemian waxwings do have very large livers, relative to their size, Larivee says.

“So they really are meant to be able to handle higher levels of alcohol. Despite that, if they do come across a tree where the berries are quite fermented, it will overwhelm their abilities to process that,” she says.

Injuries from flying into windows or vehicles while they’re inebriated can be fatal but, short of that, the birds do recover quite quickly.

There have been no reports yet but “it’s pretty early,” Larivee says. The end of September is normally when they might expect to get calls.

The Yukon animal health unit has a temporary “drunk tank” where the birds can sober up.

“Really our little drunk tanks are hamster cages that we bought at the local pet store,” she says. “It’s the same sort of thing — you need somewhere safe to sober up. We give them somewhere comfortable and dark that has water available and they seem to do quite well with that. It doesn’t take too long.”