Tracking lemming cycles in Canada’s Arctic
Canadian Museum of Nature leads research into the tundra’s “lunch box”
Ottawa, July 25, 2019 – Lemmings are among the most populous mammals in Canada’s Arctic. These plant-eating rodents may be tiny, but the cyclical rise and fall of their numbers has a large impact on their Arctic predators—from the Arctic fox and ermine, to the snowy owl, gyrfalcon and others.
Understanding the ebb and flow of lemming numbers and their links to tundra biodiversity is the focus of research led by Dr. Dominique Fauteux, a Canadian Museum of Nature research scientist and mammologist. There are four species of lemmings in the Canadian Arctic.
“Lemmings they are known to have a relatively consistent three-to-four-year cycle when their population grows, peaks, then diminishes and crashes,” explains Fauteux, who has worked in the Arctic since 2011, when he began his northern ventures as a student at Laval University. “Each phase of growth and decline has been well documented, but we still need to learn more about the reasons for this boom-and-bust scenario.”
Since joining the museum in 2017, Fauteux is leading his own research program and has been setting up base for almost two months this summer in three areas of Canada’s Arctic. He is working with colleagues to track and monitor populations of lemmings and their predators near Salluit, along Hudson Strait in Nunavik, Quebec (June 11 to June 18); on Bylot Island in Nunavut’s High Arctic (from June 22 to July 16); and around Cambridge Bay, Victoria Island, Nunavut (from July 25 to August 8).
The locale on Bylot Island has been the most studied, partly due to an active research program through Laval’s Centre for Northern Studies. Fauteux inaugurated the Salluit field program in 2018—he plans to return there in years to come for what he anticipates will be a fruitful locale to study and monitor populations of the Ungava collared lemming (Dicrostonynx hudsonius).
The general approach at each locale is to set up live traps in a grid that may cover an area up to 11 hectares. In each trap, peanut butter and a slice of apple lure the lemmings, which are then measured, tagged and released. Once back in his museum lab in Gatineau, Quebec, Fauteux analyses demographic data such as survival and reproduction rates in order to compare populations at different sites.
When at their peak, lemmings are known to increase their numbers about 100-fold over a nine-month period. “As with many small mammals, lemmings prioritize reproduction over individual preservation to ensure their survival,” explains Fauteux. In winter, they live under the snow cover, forgoing hibernation and eating tundra plants to survive then breed. Come the spring, predators feast on the lemmings, relying on them as their “lunch box”. Lemming numbers decline with predation by the end of summer.
Reasons for the cyclical, year-to-year variation are still not fully understood, and they may vary depending on the location, the presence of different predators and the interactions among them. “Some birds will reproduce with greater ease because their usual predators, such as the Arctic fox, will take advantage of the fact that lemmings are plentiful and easy to catch,” says Fauteux.
Research in Norway suggests that competition for mosses by other animals may cause a decline in lemming populations. A three-year study from Bylot Island, published by Fauteux in 2018, backed up the hypothesis that a large number of predators may contribute to the population decline.
Fauteux notes that climate change may also start having an impact on lemming populations. With a warmer climate, falling rain creates a hard crust on the snow surface, making it more difficult for the lemmings to find a winter home and access the plants underneath.
Dominique Fauteux’s research is supported by the Canadian Museum of Nature, as well as the Centre d’Études Nordiques, Polar Knowledge Canada, the Polar Shelf Continental Program (NRCAN), Air Inuit, and First Air.
Photos available upon request.
Saving the world through evidence, knowledge, and inspiration! The Canadian Museum of Nature is Canada's national museum of natural history and natural sciences. The museum provides evidence-based insights, inspiring experiences and meaningful engagement with nature's past, present and future. It achieves this through scientific research, a 14.6 million specimen collection, education programs, signature and travelling exhibitions, and a dynamic web site, nature.ca. The CMN’s National Herbarium of Canada houses more than one million specimens of vascular plants, lichens, bryophytes, and algae.
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