Climate Change May Mean Fewer Babies for Marmot Mothers
Earthwatch researchers have found that a thinner snow layer in winter may result in a decrease in litter sizes for marmot moms.
Decreasing litter size of marmots over time: a life history response to climate change
The way that plants and animals respond to climate change varies widely among species. In the French Alps, Earthwatch teams are monitoring marmots and have found a continuous decrease in litter size of Alpine “marmot mesdames” since 1990.
The study, led by Marion Tafani, Ph.D. student at Université Claude Bernard Lyon 1, shows that litter size has decreased over time because of the general thinning of winter snow cover repeatedly reported to occur in the Alps.
Alpine marmots have to spend energy to maintain their body temperature above 5°C, so a thinner snow cover during winter reduces the ground’s insulation layer and means that frost reaches deep underground, increasing the fat depletion of marmots.
Earthwatch support was essential to the collection of data needed to make this discovery, said researcher Dr. Aurélie Cohas. “Without Earthwatch, continuing this project would not have been possible! We really hope that the work will bring important new insights to understand what species are actually facing and what will be the consequences.”
Interestingly, the results contrast with a recent study on North American yellow-bellied marmots, whose body mass is believed to increase during earlier springs. This new study emphasizes that even for closely related species with similar ecological niches, it may not be wise to extrapolate responses to climate change from one species to another.
Read Decreasing litter size of marmots over time: a life history response to climate change? as it appeared in Ecology Volume 94 (March 2013).