Rudolph is shrinking: Climate change is starving Santa's reindeer

A reindeer on the Norwegian island of Svalbard. BMJ | Shutterstock)

Reindeer are shrinking, and it's not because they're dieting for the holidays. Instead, new research suggests that climate change is making it harder for them and their unborn babies to survive extreme winters.

The discovery is the result of 16 years of research on reindeer living in Svalbard, a Norwegian archipelago between Norway and the Arctic. In 1994, the average weight of adult reindeer in Svalbard was 120 pounds (55 kilograms), but in 2010, they averaged less than 108 pounds (49 kilograms), an average weight loss of 10 to 12 percent, said lead researcher Shi says Steve Alban, a retired population ecologist at the James Hutton Institute in Scotland.

He said the weight loss was associated with warmer winters and warmer summers. He said reindeer usually mate in late October and give birth in early June. During cold, dry winters, Alben said, reindeer, including those that are pregnant, scour the snow for lichens, slow-growing organisms that are part fungus and part algae. "The surprising fact about reindeer is," Albon said, "but warm winter temperatures bring more rain, not snow. Then, when temperatures drop When the wet ground froze like an ice rink, the reindeer's delicious moss became stuck under the ice, and without access to food, hundreds (if not thousands) of the reindeer died, and the surviving gestations Reindeer either lose fetuses or give birth to calves, Alban said. In fact, that happened in Siberia between 2013 and 2014, according to a study published in November 2016 in the journal Biology Letters. 61,000 reindeer starved to death during a rainy and snowy day

In the 20 years we have been working there (in Svalbard), temperatures have risen. 9 degrees Celsius [16.2 degrees Fahrenheit]," Albon told Science Live. "It's more likely that temperatures during these periods would have been above freezing, and if there was any precipitation, [freeze would later form].

Initially, researchers noted that these ice events occurred every six years - But then ice events started happening every other year, in 2008, 2010 and 2012, and "we realized it was related to climate warming," Albon said. The Arctic is warming faster than anywhere on Earth, especially this part of the Arctic. Reindeer are shrinking

Albon and his Norwegian colleagues initially visited Svalbard's reindeer to learn about them. Response to parasites. When they measured and weighed the reindeer year after year to see the parasite's effects, they noticed a disturbing pattern: In 1996, 2002 and 2008, the ice rink In addition, there were dramatic changes in the number of pregnant female deer in the same year as the event, and the researchers also documented a decrease in adult deer bone size and body weight from the 1990s to the early 2000s, the researchers said. ,

This happened amid warming summers, which led to an increase in vegetation for the reindeer to eat, with summer temperatures rising by about 2.7 degrees Fahrenheit (1.5 degrees Celsius) over a 20-year period, Albon said. ), 1.5 degrees Celsius doesn't sound like much in the summer, but if you go from the average of 6 degrees Celsius (42.8 degrees Fahrenheit) in July to 7.5 degrees Celsius (45.5 degrees Fahrenheit), you'll find that your Vegetation productivity doubled," Albon said. "This is a very significant change.

Even though there is a lot of food in the summer, the reindeer winter continues. They lose weight and have fewer fetuses, so there is fetal mortality. [Species Success Story: 10 animals come back from the brink]

Instead, "If the winter is cold and dry, the mothers can get food, the calves will be born at the right size and may be more survivable, He said this early growth, even in the womb, determines the rest of life. When Svalbard warms and food germinates, the reindeer mate more easily. He said this means that despite frequent ice rinks in the winter , serious, the reindeer population is still growing

As the population increases, winter resources are limited, which may partly explain the phenomenon of "shrunk" reindeer, Albon and his colleagues reported in their study. "Whatever the cause of shrinkage," the report reads, "smaller reindeer face different challenges than their normal-sized counterparts. These smaller reindeer have a disadvantage in winter." , because their metabolism is higher than that of normal-sized reindeer, but there is less food available for them to eat. However, during warmer summer months, these smaller reindeer may have an advantage because they can more easily dissipate heat, which is when they are nursing. That's high at times, Albon said.

If too many reindeer shrink, that could also spell bad news for the herd.

If the number of mature deer in the caribou population exceeds 110 pounds (50 kilograms) by a large margin in April, the population will increase. But if the reindeer mostly weigh less than that, their numbers will decline, Albon said. Temporarily, researchers are waiting for reindeer born in the past few years to reach 6 years of age. That is adulthood. Only then can researchers better understand the impact of climate change on caribou populations, he said. However, another study presented at the American Geophysical Union meeting on Monday (December 12) found that climate change may be responsible for the decline of reindeer in northern Russia.

Reindeer are not the only animals being “shrunk” by climate change. This phenomenon is not a new one—fossil evidence shows that beetles, bees, spiders, and even kangaroos shrank when the Earth warmed in the past, Live Science reported in 2011.

Recent reports link shrinking bison, salamanders and other animals to climate change.

Reindeer research, a paper on life sciences presented at the British Ecological Society meeting in Liverpool, UK, on ??Monday, has not yet been published in a peer-reviewed journal