14 DAY TRIAL // A new research published in the journal IBIS, draws attention on the fact that winter sports affect the habitat of indigenous mountain birds, and asks for conservation measures.
Winter sports passionate can't wait for the first snow to fall, so they can grab their skis, their snowboards or sleighs, and go on a small vacation at the mountainside.
And because everybody wants to go where everybody else does, the mountain ranges of central Europe – the Alps, attract thousands of tourists every year.
The problem the conservationists fear here, is that this annual tourist invasion can threaten indigenous bird species, like the iconic alpine Capercaillie, whose numbers are already rapidly declining.
Lead author Dominik Thiel, from the Swiss Ornithological Institute and his team, monitored the populations of alpine Capercaillie in Germany and Switzerland close to recreation sites during two winter seasons.
During this time, they analyzed 1130 samples of Capercaillie droppings, and found that those closer to locations with winter recreation activities had very high stress hormone levels.
These birds are very sensitive to winter tourism, mainly because during this time of the year, their feeding is restricted to conifer needles – that have a low nutrient content and are difficult to digest.
So, in order to survive, they need a long digestion time and must conserve that low energy intake, and the problem is that escaping from humans (who are perceived as predators) demands a lot of effort and energy spending, energy they don't have.
Thiel explained that “winter is always the most energetically demanding season of the year for any species surviving in the mountains.”
The Capercaillie (Tetrao urogallus), is also known as the Wood Grouse, and it is the largest member of the grouse family, renowned for its mating display.
It is usually found in the alpine regions of Germany and Switzerland but these past years, its population has suffered a severe decline.
“Alpine habitats across Europe remained relatively undisturbed until the beginning of the last century, but today human outdoor recreation areas coincide with the winter habitats of many shy and endangered species,” said Thiel.
"The Western Capercaillie has suffered rapid population declines during recent decades.
“However, little is known about their susceptibility to human recreation activities.
"The fact that this coincides with intense human disturbance has clear physiological and behavioral implications for Capercaillie.
"We believe that Capercaillie are especially sensitive to winter recreation, and the risk for negative effects is high.
“The access of people to undisturbed Capercaillie winter habitats should therefore be prevented.
“Recreation activities should be kept away from core Capercaillie wintering areas, especially during the physiologically most demanding winter days,” recommend the researchers.