The Alpine finch is at risk, threatened by tourism and beyond

The Alpine finch, but also the Alpine deaf and the white ptarmigan, are high altitude birds that are at risk of extinction for a series of reasons, including the fact that, also due to climate change and the impact of man , specimens reproduce more and more often between 'relatives'

MILAN – Tourism and crossbreeding 'between relatives' threaten the survival of high altitude birds such as the snow finch, the European Alpine finch and the white ptarmigan.In addition to climate change and the alterations of mountain habitats caused by man, weigh on the growing tourist pressure and related infrastructures.This was revealed by research born from a collaboration between the Alto Adige Museum of Natural Sciences, the State University of Milan, the University of Oulu, the Trento Science Museum (MUSE) and Eurac Research, the results of which have just been published in the Journal of Biogeography .Crucial to evaluate the long-term survival chances of these animals is represented by possibility of exchanging individuals (and therefore genes) between different reproductive areas.In particular, smaller and more peripheral populations may be strongly affected by a decrease in immigration.

THE REPRODUCTIVE AREAS ARE DISTANT

Based on genetic analyses based on dozens of specimens from various breeding areas in Trentino-Alto Adige and Lombardy, it emerged that the exchange of individuals between breeding areas (i.e. dispersal) is affected by the distance between them, with a strong decrease already starting from 20- 30 kilometers.In fact, 20% of the individuals sampled were born to parents related to each other at least at the level of first cousins, if not even more closely.

TOO MANY CROSSINGS INCREASE THE RISK OF EXTINCTION

“These high levels of inbreeding are particularly alarming, because they can lead to the expression of deleterious recessive mutations, decrease the probability of survival of individuals and their reproductive success", comments Francesco Ceresa, ornithologist at the Museum of Natural Sciences of Alto Adige and first author of the study.
Mattia Brambilla, ecologist at the Department of Environmental Sciences and Policies of the University of Milan and co-author of the work, who has been involved in research on Alpine avifauna for years, underlines how these results "add further elements to the complex mosaic of effects of climate changes on high altitude species, which already include range contractions, alteration of environments of foraging and exacerbation of impacts of human activities.The combined effect of all these factors, often greater than the sum of the individual elements, is at the basis of the declines that are already observed and which will become even more marked in the decades to come."