According to a 16 year long study in the Norwegian archipelago of Svalbard, climate change has been linked to the declining average weight of Reindeer. In an interview with Live Science, lead study researcher Steve Albon, an emeritus population ecologist at the James Hutton Institute in Scotland, said the drop in weight was linked to warmer winters and summers.
Reindeer rely heavily on lichen as a food source in the winter. With the rising temperatures causing more rain and frequent thawing leading to subsequent freezing, the lichen becomes inaccessible due to the refreezing of precipitation causing an ice layer over the precious sustenance these animals so heavily rely on.
Warm winter temperatures have increasingly brought rain, not snow, Albon said. Then, when temperatures drop, the wet ground freezes like an ice rink, with the reindeer’s tasty lichen stuck beneath the ice.
“It’s more likely that you’ll get these periods where the temperatures go above freezing, and if there’s any precipitation, [it later freezes]. In the winter, over the 20 years we’ve been working there [Svalbard], the temperature has gone up 9 degrees Celsius [16.2 degrees Fahrenheit],” – Albon
Unable to get to their food, hundreds, if not thousands, of reindeer die, and pregnant reindeer that survive either lose their fetuses or give birth to smaller calves. In fact, 61,000 reindeer starved to death in Siberia following a rain-on-snow event in 2013 to 2014, according to a November 2016 study published in the journal Biology Letters.
“In 1994, the adult reindeer in Svalbard weighed an average of 120 lbs. (55 kilograms), but in 2010, they weighed less than 108 lbs. (49 kg), on average — a 10- to 12-percent drop in weight”- Albon
While other factors influence the weight of the reindeer, it is believed climate change is the primary cause for the weight loss. For the time being, the researchers are waiting for the reindeer born in the past few years to reach age 6, when they become mature adults. Only then will the researchers have a better idea of how the current climate change is affecting the reindeer’s population numbers.
Reindeer are hardly the only animal that is “shrinking” due to climate change. The phenomenon isn’t a new one — when the planet got warmer in the past, beetles, bees, spiders and even pocket gophers also shrank, according to fossil evidence, Live Science reported in 2011.