It turns out that humans aren’t the only species that enjoy a boozy drink or two.
A recent University of California study found that hummingbirds aren’t opposed to drinking sugar water with alcohol, according to a UC Berkeley press release. In fact, the team of researchers says that hummingbirds “happily” sip liquids with up to one percent ABV.
The study’s findings were recently published in the academic journal Royal Society Open Science. According to the study, the natural process of fermentation can cause a mixture of sugar and water to produce ethanol. This means that the sugar-water mixtures, often added to outdoor feeders to attract birds, can end up fermenting into a low-ABV liquid over time. The team’s research showed that sugar-water in 350-milliliter pinch-waist hummingbird feeders can reach .05 percent ABV after about two weeks outdoors.
Under the direction of UC Berkeley biologist Robert Dudley, a group of student researchers tested whether hummingbirds were attracted to that small amount of alcohol in sweetened water. The birds demonstrated interest in sugar-water at one percent ABV and consumed the same amount as they did standard sugar-water. When researchers offered them a two percent ABV mixture, however, the hummingbirds only sipped half of the normal amount.
While hummingbirds will consume a relatively high amount of alcohol for their size, rest assured that your backyard bird feeder isn’t over-serving any of your feathered friends. The study’s authors say that hummingbirds’ uniquely high metabolism rates ensure they aren’t flying impaired and “aren’t becoming drunk.”
“Hummingbirds are eating 80% of their body mass a day in nectar,” Dudley says in the release. “Maybe, with feeders, we’re not only farming hummingbirds, we’re providing a seat at the bar every time they come in.”
Going forward, Dudley plans to study the amount of ethanol that naturally occurs in flower nectar.