When we think of alcohol in nature, we usually think of fermented fruit—not flower nectar. But nectar can ferment too, especially when yeasts break down sugar. So what happens when nectar-feeding birds drink it?
In this episode, we explore a surprising study on Anna’s hummingbirds, tiny birds with extremely fast metabolisms that drink huge amounts of nectar every day sometimes from a window bird feeder. Researchers wanted to know whether hummingbirds notice—or avoid—small amounts of alcohol in their food.
To find out, scientists offered hummingbirds a choice between sugar water with no alcohol, 1% alcohol, or 2% alcohol. The results were striking. The birds did not avoid nectar with 1% alcohol at all—they drank it just as readily as alcohol-free nectar. But when the alcohol level reached 2%, the birds clearly drank less (shown in the feeding preference graph on page 4).
The takeaway? Low levels of alcohol don’t bother hummingbirds, and may even be a normal part of their diet in nature. This suggests hummingbirds—and possibly other nectar-feeding birds—are adapted to handle small amounts of fermented sugar without harm.
This episode reveals how something as ordinary as nectar can hide unexpected chemistry, and how animals quietly adapt to it.
