Researchers at Oregon Health and Science University recently got a bunch of birds drunk in the name of science.

Christopher Olson and his colleagues study birdsong to learn about human speech because birds learn to sing in much the same way that we learn to talk. Birdsong and human speech are even controlled by the same gene.

Olson was curious if alcohol would impair birdsong just as it impairs human speech, so he arranged for some zebra finches — birds which have long been used as a model to study human vocal learning — to have a happy hour.

"We just showed up in the morning and mixed a little bit of juice with 6 percent alcohol, and put it in their water bottles and put it in the cages," Olson told NPR. "At first we were thinking that they wouldn't drink on their own because, you know, a lot of animals just won't touch the stuff. But they seem to tolerate it pretty well and be somewhat willing to consume it."

The birds reached blood alcohol levels of .05 to .08 percent, which is a fairly inebriated state for birds because of how they metabolize alcohol.

In their drunken state, the finches weren’t able to sing like normal.

"The most pronounced effects were decreased amplitude and increased entropy," the researchers wrote in a paper recently published in PLOS One.

In other words, the birds’ songs got quieter, less organized and a little slurred.

However, not all parts of the songs were affected in the same way. Zebra finch songs are composed of syllables with distinct acoustic structures, and some of the inebriated birds’ syllables were more slurred than others.

Olson and his colleagues think this could indicate that alcohol affects some parts of the finches’ brains more than others.

In a future study, Olson wants to look at how alcohol affects birds’ abilities to learn new songs.

Although the finches in this study were purposely intoxicated, it’s not uncommon for wild birds to get a little tipsy. This most often occurs in the winter in the Northern Hemisphere when birds consume berries that ferment when weather turns cool.

Some bird species are more likely to overdo it than others, such as the Bohemian waxwing, which feeds almost exclusively on fruit.

Inebriated waxwings are so common in Yukon, Canada, that wildlife officials have miniature “drunk tanks” where the birds can rest until they’re sober enough to return to the wild.

The tanks are small cages with water and bedding that are kept in dark, quiet places at the Animal Health Unit.

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