Researchers at the University of Durham have studied changes in body size of the chamois (rupicapra rupicapra) of the Italian Alps over the past thirty years. To their surprise, they discovered that pups weigh 25% less than animals of the same age in the 1980s. In recent years, this phenomenon that appears to shrink the body has been identified in different animal species, but the decrease The size of chamois, according to scientists, is striking for its speed and magnitude.
As in other cases, the reason has been related to climate change. "The decrease in body size attributed to climate change has been widespread in the animal kingdom, with many fish, birds and mammals getting smaller and smaller," explains Tom Mason of the School of Biological and Biomedical Sciences, Durham University . “However, the declines we see here are staggering. Impacts on the weight of chamois could pose real problems for the survival of these populations. '
The team delved into long-term records of the body weights of these animals provided by hunters in the Italian Alps.
In this way, he discovered that the declines were strongly linked to the warming of the climate in the study region, which became between 3 and 4ºC warmer during the three decades of the study.
To date, most research suggests that this is because climate change is reducing the availability or nutritional content of animal feed. However, this study found no evidence that the productivity of alpine meadows grazed by chamois had been affected by the warming climate. Instead, the team believes that the high temperatures are affecting how the goats behave.
Impact on domestic livestock
"We know that Chamois cope with hot spells by resting more and spending less time searching for food, and this may be restricting their size more than the quality of the vegetation they eat," explains Stephen Willis, at the School of Science. Biological and Biomedical, from Durham University. "If climate change leads to similar behavior changes in body mass in domestic livestock, this could have an impact on agricultural productivity in the coming decades," he adds.
According to the authors, the future of these chamois is unclear. According to Philip Stephens, also a co-author of the study, in Durham, “the body mass of young animals is critical to their ability to survive harsh winters. However, whether that becomes a problem will depend on the balance of future climate change between the seasons.
To counteract the decline in body size in the future, the researchers say in the journal Frontiers in Zoology that it may be necessary to maintain chamois populations at lower densities, perhaps through changes in hunting legislation.
A similar effect has been observed in Soay sheep, a wild breed that lives on the remote Scottish island of Hirta, in the St. Kilda archipelago. These sheep are getting smaller, apparently also due to climate change.