Bird Nest Ciggy Butts Lower Parasite Load

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Cigarettes are bad for your health. But that’s only if you smoke ‘em. If you use them to line your nest, they might actually do you some good. Because birds that decorate their digs with discarded cigarette butts are less bothered by parasites. That’s according to a study in the Royal Society journal Biology Letters. [Monserrat Suárez-Rodríguez, Isabel López-Rull and Constantino Macías Garcia, Incorporation of cigarette butts into nests reduces nest ectoparasite load in urban birds: new ingredients for an old recipe?]

When building a nest, birds tend to make do with the materials at hand—or at beak. Twigs and leaves are popular choices. But what about city birds? Some reach for cigarettes, or at least the fluffy white fibers found in their filters.

Scientists got to wondering whether this habit might provide the birds benefits other than comfy bedding. So they grabbed the nests of finches and sparrows that were living on the campus of the National University of Mexico. That’s in the heart of Mexico City. And they found that the nests that were festooned with the most filter fiber had the lowest numbers of mites.

Could be that the little bloodsuckers are turned off by nicotine. Or maybe they’ve heard about the dangers of secondhand smoke. But for the birds, a butt a day might just keep mites away.

—Karen Hopkin

[The above text is a transcript of this podcast.]

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