CC BY 2.0 / John Benson / Another nice morning to go shoot birds, but the only unobstructed shot I got was another male house finch. Mexican lentilsCC BY 2.0 / John Benson / Another nice morning to go shoot birds, but the only unobstructed shot I got was another male house finch.
Some birds have learned how to collect cigarette butts and «decorate» their nests to repel parasites, said scientists in a paper published in the Journal of Avian Biology.
«We found that the finches were more inclined to decorate their nests with cigarette butts in those cases, if they’ve got mites or other parasites, and they were found and brought more butts in those cases, if the mites in the nest were alive and not dead. All of this points to the fact that they use cigarettes to «smoke» mites from nests,» said Garcia, Constantino (Constantino Garcia) from the National Autonomous University of Mexico in Mexico city.
Garcia and his colleague Monserrat Suarez-Rodriguez (Monserrat Suarez-Rodriguez) for several years, watching the behavior of lentils (the small bird from the family of finches), as well as some other birds who live in the vicinity of Mexico city and other major cities.
Five years ago, Suarez-Rodriguez and Garcia noticed that birds often pick up cigarette butts and bring them into the nest. Scientists have tracked the behavior of lentils and found that cigarettes could attract their attention, because the nicotine repels ticks and other biting insects.
With these conclusions agree not all bird watchers – many biologists have indicated that birds may collect cigarette butts for other reasons, for example due to the presence of soft wool, and antiparasitic effect is a nice (and unknown for birds) «bonus». This prompted researchers to repeat the experiments.
To test his theory, Garcia and Suarez-Rodriguez «interfered» in the lives of three dozen families of birds. Waiting for the birth of the Chicks, the scientists changed the litter in nests of ten pairs of finches, removing from there all the parasites, added new ticks in the «home» for another ten bird families, and the rest «threw» the dead parasites.
After that, biologists scattered cigarette butts and a cigarette in the tree where birds lived, and began to monitor the behavior of finches.
Observations have shown that the presence of mites does cause birds to purposefully look for cigarette butts and bring them to the nest. On average, the nests of the parasites contained about 40% more wool of cigarette filters than in the «pure», and noticeably more in comparison with nests where there were dead mites.
The scientists noted that the birds are well distinguished smoked and entire cigarette and preferred to collect only the butts. This finally confirmed the hypothesis Suarez-Rodriguez and Garcia, formulated in 2012.
Such protection of nests against parasites, as scholars have noted, goes unnoticed for the birds. Nicotine is not only repels or kills insects, but also damages the DNA of the birds themselves. However, according to biologists, the advantages of such a use of cigarettes is still more than minuses.