Svalbard reindeer thrive as they shift diet towards ‘popsicle-like’ grasses

Increased plant growth due to warmer climate appears to be prompting change in eating habits

As the Arctic warms, concern for the plight of Santa’s favourite sleigh pullers is mounting. But in one small corner of the far flung north – Svalbard – Rudolph and his friends are thriving.

Warmer temperatures are boosting plant growth and giving Svalbard reindeer more time to build up fat reserves; they also appear to be shifting their diets towards “popsicle-like” grasses that poke up through the ice and snow, data suggests.

Smaller and plumper than their Lapplandish cousins, yet boasting impressive antlers nonetheless, Svalbard reindeer inhabit almost all non-glaciated areas of the Svalbard archipelago, which sits just 500 miles (800km) from the North Pole.

Like other Arctic regions, Svalbard has experienced thicker snowfall, and more frequent rain-on-snow events – where rain falls on an existing snowpack and freezes – in recent years, making it harder for reindeer to dig for food.

Reports of mass reindeer starvations in Russia, and declining caribou populations in Canada and Alaska, have also prompted concern for Svalbard’s reindeer. Yet, in the most productive parts of the archipelago, reindeer populations have flourished in recent decades.

Two Svalbard reindeer battle for control of a harem
Two Svalbard reindeer battle for control of a harem. Photograph: Stefano Unterthiner/PA

To investigate what might be driving the population increase, Tamara Hiltunen, a doctoral student at the University of Oulu in Finland, and her colleagues turned to annual blood samples collected in late winter as part of a long-term monitoring study. By comparing the proportion of carbon and nitrogen isotopes in these samples, they could infer what kinds of plants the reindeer had been eating in preceding weeks.

The research, published in Global Change Biology, suggested that between 1995 and 2012 – a period marked by the normalisation of rain-on-snow events, increased summer temperatures and a growing reindeer population – there was a dietary shift away from low-growing mosses and towards grass-like “graminoid” plants.

“The erect nature of the graminoid stems allows that forage to be available to the animals, even though you might have a centimetre or so of ice,” said Prof Jeffrey Welker at the University of Oulu, who supervised the research. “You have the equivalent of popsicle sticks, which are nutritious enough that those animals can sustain themselves, even during these stressful periods of winter.”

Higher soil temperatures and greater amounts of reindeer droppings and urine falling on the ground are also boosting the growth of graminoids, which may further benefit the Svalbard reindeer.

“This is definitely encouraging news,” said Prof Jaakko Putkonen at the University of North Dakota, whose research previously predicted an increase in Arctic regions affected by rain as the century wears on. “However, nature is an endless web of interdependent variables. Some of the upcoming changes may be good to the reindeer and some may be detrimental.

“For example, from Scandinavia there are reports of rain on snow promoting the growth of fungi (eg toxic moulds) under the snowpack due to warmer conditions which has led the reindeer to avoid those areas. They may be trading one challenge for another one.”

Welker also cautioned that events in Svalbard may not apply to other regions of the Arctic.

“Just as we see signs that a reindeer population on Svalbard might have some ways of adapting and adjusting to these changes, that could allow them to sustain themselves, we’ve got other groups in Alaska, for instance, that are declining.

“It really speaks to the complexity of the Arctic. Events that are happening in one place are not identical to those that are happening in others.”

However, for Svalbard’s reindeer, the future looks bright – and the archipelago a promising recruitment ground should Santa need further helpers. Given their diminutive size, though, he may need to invest in a smaller sleigh.

“I’m sure they could do it, they just might be a little bit obese,” said Hiltunen. “But maybe if they lived with Santa, they wouldn’t need so much fat to keep themselves alive.”


Linda Geddes Science correspondent

The GuardianTramp

Related Content

Article image
Country diary: the vanguard from Svalbard
Caerlaverock, Dumfries and Galloway: Barnacle geese take off in a clatter of wings and yapping calls, swirling over the merse

Stephen Rutt

05, Oct, 2020 @4:30 AM

Article image
Svalbard job vacancy: polar bear spotter wanted
Arctic archipelago seeks person to stand guard while researchers carry out fieldwork. Firearms skills, or loud voice, may come in handy

Helen Russell

16, May, 2013 @12:59 PM

Article image
Sweden’s biggest wolf cull starts but campaigners fight on
Hunters are allowed to kill 75 wolves from an endangered population of 460. On one hunt that the Guardian joined, they went home empty-handed

Helena Horton and Beata Furstenberg in Sandviken

02, Jan, 2023 @4:40 PM

Article image
Polar bear DNA from footprints in Arctic snow reveal bloody killing of seal
First of its kind CSI-style technique to gather genetic material from animals could help track plight of endangered species

Damian Carrington

02, Sep, 2014 @2:52 PM

Article image
Starved polar bear perished due to record sea-ice melt, says expert

Climate change has reduced ice in the Arctic to record lows in the past year, forcing animals to range further in search of food

Damian Carrington

06, Aug, 2013 @12:17 PM

Article image
Marine reserve status for whole Arctic region is best way to protect it
Letters: This would mean that no fishing could take place (be licensed) unless that proposal to fish could prove that it was not injurious


15, Mar, 2016 @1:21 PM

Article image
The Guardian view on climate change: bad for the Arctic | Editorial
Editorial: Warmer winters may seem good for Arctic animals. In fact they can be deadly


27, Dec, 2016 @6:20 PM

Article image
Lynx facing extinction in France as population drops at most to 150 cats
Urgent action needed as DNA tests show their genetic diversity is so low they could vanish from the country in 30 years

Ian Sample Science editor

13, Feb, 2023 @5:00 AM

Article image
Puffin nesting sites in western Europe could be lost by end of century
Experts create guide to help save seabirds from bleak future caused by global heating

Helena Horton Environment reporter

08, Dec, 2022 @12:01 PM

Article image
Polar bear could be saved if emissions are cut, says new study
Ice caps not likely to face rapid, irreversible melting as previously thought, researcher claims – meaning polar bears could survive

Shanta Barley

15, Dec, 2010 @5:46 PM