Smoking kills. But if you’re a bird and if you want to kill parasites, that can be a good thing. City birds have taken to stuffing their nests with cigarette butts to poison potential parasites. Nature reports:
In a study published today in Biology Letters, the researchers examined the nests of two bird species common on the North American continent. They measured the amount of cellulose acetate (a component of cigarette butts) in the nests, and found that the more there was, the fewer parasitic mites the nest contained.
But what if parasites just don’t like the little tube structure of cigarettes or the paper? How do we know it was the nicotine? The researchers thought of that as well. They used traps to lure parasites to nests they had built. Half of those traps had filters from smoked cigarettes and half had filters from unsmoked cigarettes. Here’s Nature again on what they found:
After 20 minutes, the team found that devices with unsmoked butts had many more parasites attached to them than devices with smoked butts — which contain more nicotine as the cigarette smoke has passed through them. Indeed, in nests that contained bird eggs, traps with unsmoked butts caught on average more than twice as many parasites.
Which left researchers wondering whether birds would learn to prefer cigarettes with more nicotine in them than others. They also wonder whether this nicotine could have ill effects on the birds or their chicks. As yet, no one knows.
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