Binoculars swinging around the neck we unzipped door number 14 of our outdoor ADVENTure calendar. Today we were on the search of a large prize. A species ‘dear’ to my heart, and one that has been in the headlines this week. Today we were on the lookout for reindeer.
Crunching through a fresh snowfall we spotted a distant movement along a treeline. We stopped, caught our breath, crouched, and slowly adjusted the viewfinder on the binos. There they were. Lined up in front of the woodland. Eight reindeer.
As they shovelled the snow out the way with their antlers there was a gentle tinkling sound. And when one lifted it’s head and sniffed the air we noticed a red bridle sitting across it’s nose. Had we stumbled across Father Christmas’ herd? Yet, something was wrong… The picture wasn’t quite right… The reindeer looked smaller than the ones I remembered from picture books…
Father Christmas’ reindeer had shrunk!
As absurd as that may sound, research announced at BES2016 (British Ecological Society annual meeting) this week by Steve Albon of the James Hutton Institute, demonstrates that reindeer are shrinking over time. In 1994 Albon and colleagues began weighing reindeer in Svalbard, Norway, since then adult weight has decreased from 55kg to 48kg (in 2010), a drop of 12%.
Albon believes that climate change is influencing this decrease in size. Svalbard is experiencing warmer summers, 1.5°C warmer to be precise. This increase in temperature actually means that there is more food available for the reindeer in the summer, females are able to gain more weight and conceive more calves.
However, Svalbard is also experiencing warmer winters, and this results in more rain. When the rain falls on snow it freezes. Reindeer antlers act as perfect shovels to dig through the snow, and it is because of this that reindeer are the only deer species where both sexes have antlers. But antlers are not so effective on ice and the reindeer are effectively cut off from their food source. This lack of food in the winter leads to reindeer starving, aborting calves or giving birth to much lighter young.
In addition, population numbers of reindeer have doubled in the past 20 years, which has resulted in increased competition for food sources. This competition for food could, in turn, be causing a decrease in overall body weight of the deer.
Which, as the press release states, beggars the question as to whether Father Christmas will need to recruit more, smaller, deer from the swollen populations for his sleigh. As a final thought though, if he does, it’s likely that – because male and female reindeer shed their antlers at different times – those recruits will actually be female.
Don’t forget to let us know what your outdoor Christmas traditions are for a chance to win a copy of Alastair Humphreys ‘Microadventures’!