Tipping against tick attacks Birds protect their nest with cigarette remains from parasites

To protect against parasites: Birds incorporate cigarettes into their nests
When health professionals point out how best to protect themselves from ticks, cigarettes are never mentioned. But other creatures can apparently help with the glowing stalks. According to a study from Mexico, birds build targeted cigarette butts to protect themselves from parasites. Native animals show similar behaviors - some of them even use medicinal herbs.

Finches deliberately put cigarette butts in nests
In a study by Mexican researchers, it has been shown that finches, who live in cities, deliberately incorporate cigarette butts into their nests. Monserrat Suárez-Rodríguez and Constantino Macías García from the Universidad Nacional Autónoma de México report in the journal "Journal of Avian Biology" that birds are using tilts to protect themselves from parasites such as ticks. Also in this country there are birds with similar behaviors - some even use medicinal plants.

Researchers have found that some birds specifically include cigarette butts in their nests. The animals apparently use the tipping to protect themselves from parasites such as ticks. (Image: Jiri Hera / fotolia.com)

Smoked butts are used for parasite defense
Already in a previous investigation, the Mexican scientists dealt with the topic.

"Urbanization is becoming increasingly interesting for biologists because it causes significant changes in species composition, species interactions and the ecological and evolutionary processes," the researchers wrote in 2012 in the journal "Biology Letters".

Even then, the experts said: "We have provided the first evidence that smoked cigarette butts can act as a parasite defense in urban bird nests."

Cigarette filters drive out ticks
As part of their current study, the two researchers have examined nests of domestic bullfinches (Carpodacus mexicanus), the news agency dpa reports.

These birds belong to the finch family. The scientists exchanged parts of 32 nests on the Unicampus. In ten nests they put live ticks, in ten they put dead ticks, the twelve remaining untreated.

It was found that especially those finches collected cigarette filters whose nests were infected by live ticks.

Until now, it was unclear whether the animals might also collect the fibers because they isolate particularly well, for example. In the study, such a heat effect could not be determined.

But the bullfinches could probably make a connection between the fibers and tick-free.

It turned out that some females that brought fiber into prepared nests did so in their original nests. According to the researchers, the birds may have learned this from earlier tick infestations.

Native bird species use medicinal herbs
As the dpa reports, Helga Gwinner from the Max Planck Institute for Ornithology in Seewiesen knows comparable behavior of native bird species.

For example, a star colony in Bavaria has specialized in yarrow and other essential oil plants as nest material. The herbs reduce bacterial growth in the nests.

"The starlings are looking for exactly these plants in the meadows. They show the flowers and herbs to the females even when courtship behavior, before they weave the plants into the nest, "said the expert, according to the agency.

Burden on the environment
According to Gwinner, the herbs also have a positive effect on the animals themselves. Thus, baby cubs that grew up in such nests were heavier, had better blood levels and better chances to return from their winter quarters in Africa.

According to the Mexican scientists, the use of cigarette stubs for the bullfinches could possibly also have negative consequences.

However, the team has not registered any long-term damage to the birds during the year-long observation of the fin nests in Mexico City. Although this needs to be studied more closely, by then the incorporation of the fibers into the nests may be considered a form of self-medication.

Thrown away cigarette butts are not only an aesthetic annoyance, but also a problem for the environment.

According to scientific studies, cellulose acetate filters do not decompose until years later. Used filters contain toxins such as tar and nicotine, which can end up in soil and water. (Ad)