Less high-quality food and less space: these are the problems that the snow sparrow may face in Switzerland in the future. Its future depends on what we do to mitigate the effects of climate change.
Sempach. - Over the past 35 years, climate change has pushed the timing of snowmelt forward by an average of 26 days. For the snow sparrow, which largely seeks nestling food at the edges of melting snowfields, this premature snowmelt is increasingly becoming a problem. Its populations have declined by nearly 15% since the 1990s.
As part of a multi-year research project, the ornithological station wants to learn more about the snow sparrow and its habitat requirements. It is already known that snow sparrows breed more in places where the snow melts later than in other locations at comparable altitudes. However, the average hatching date has changed little over 20 years despite a significant shift in snowmelt. This affects the quality of food available for rearing young and has a negative impact on young development.
Even beyond consideration of snowfield margins, the warmer climate is causing the available habitat for high alpine species to shrink. More than half of them have shifted their range upward by an average of 75 meters over the past 20 years. With an area that is 70% mountains, Switzerland has a major international responsibility for typical mountain species. For example, one in six European snow sparrows breeds in Switzerland.