Meet the reindeer

Svalbard Reindeer. Image by Peter Prokosch. Retrieved from Flickr 12/22/2022

It’s almost Christmas, so I thought the obvious animal for this Animal Friday was the reindeer!

Scientists (sadly) haven’t found any reindeer with a glowing red nose. But that doesn’t mean that reindeer aren’t super cool! Check out these cool reindeer facts:

  • Reindeer and caribou are the same
    • I always thought reindeer and caribou where separate creatures, but I was wrong! According to the San Diego Zoo, reindeer and caribou are the same species, Rangifer tarandus. Apparently, they are typically referred to as reindeer in Europe and caribou in North America. North Americans will also refer to European populations as reindeer. Domesticated animals are generally always referred to as reindeer and not caribou.
  • Reindeer antlers are LARGE
    • For their body size, reindeer have the largest antlers among all living deer species. We’re talking antlers that are as big as 51 inches (130 centimeters) for males and 20 inches (50 centimeters) for females.
  • Pictures of Santa’s reindeer show them with antlers, which means they’re almost certainly female
    • As I hinted at before, both male and female reindeer grow antlers. In fact, they’re the only deer species where both males and females grow antlers! Even though both sexes have antlers, they drop them at different times of the year. While a male will lose his antlers in November and regrow them in the spring, female reindeer keep their antlers throughout the winter and won’t drop their antlers until their calves are born in May. So it’s females, not males, that have antlers in December, and any antlered reindeer pulling Santa’s sleigh are almost certainly females as well!
  • Reindeer are incredibly hairy
    • And I mean really hairy. They have hair everywhere, even the bottom of their feet! Having this much hair keeps reindeer warm in the cold arctic where they live. Their hairy hooves also help give them a good grip on slippery ground, whether that be ice, mud, or snow. They are also the only deer species to have hair completely covering their nose. This hair helps them warm the cold air as they breath and makes them really good at smelling things like food under the snow.
  • Reindeer flock together
    • Reindeer are herd animals and travel, feed, and rest throughout the day in herds of 10 to a few hundred. During the spring, super herds of 50,000 to 500,000 animals can form as they migrate to find food. To keep track of each other in the herd, reindeer will “talk” with each other with snorts and grunts. Calves will also keep track of their mothers by calling out with bleats.
Reindeer herd. Image from Natalia_Kollegova on Pixabay. Image retrieved 12/22/2021
  • Reindeer can see UV
    • Human vision is pretty good, but reindeer can see things that we can’t. More specifically, reindeer can see ultraviolet light! Being able to see UV may help reindeer protect their eyes from the sun reflecting off the snow. It also can help them see food and predators hiding within the snow!
  • Reindeer eyes change color (but we can’t see it)
    • Reindeer live in the Arctic, where the sun never sets in the summer and never rises in the winter. This means that their eyes have to deal with large differences in light amounts across the year. How do they deal with it? By changing the color of their tapetum lucidum, a part of the eye behind the retina of some animals. In the summer, it’s gold. But in winter, it turns blue; this decreases the amount of light that is reflected out of the eye and increases light sensitivity. Unfortunately, we can’t see this color change, since it occurs in the back of the eye. It’s still a neat trick!
  • Domestic reindeer have been around for a LONG time
    • We’re talking about domestication around 3,000 years ago (with some scientists even suggesting 7,000 years ago!). And it doesn’t look like they’ll go away anytime soon – reindeer are still used today as beasts of burden and farmed for their milk, meat, and hides.
  • Reindeer don’t eat carrots…
    • If you’re like me and my siblings, you may have left carrots out on Christmas Eve for Santa’s reindeer to snack on. Unfortunately, reindeer don’t eat carrots! Their natural diet is full of leafy stuff instead, like mosses, herbs, grasses, and the shoots and leaves of shrubs and trees. In the winter, they will stick to lichen and fungi. But would a reindeer chomp a carrot if they were offered one? Almost certainly not. Reindeer don’t have teeth on their upper jaw and have no incisors to eat carrots even if they wanted to.
  • But they may eat rodents
    • Like a lot of animals we think of as “vegetarians,” reindeer aren’t above snacking on other animals when they get the chance. Lemmings (a small rodent) and bird eggs offer quick sources of protein, and anecdotal stories have reported reindeer chowing down when these small animals are accidentally trampled. Is this meat-eating a common occurrence? We don’t have the data, but probably not. Reindeer aren’t predators hunting lemmings; they just won’t turn down the chance for a free snack.
  • Reindeer are in trouble
    • Unfortunately, reindeer populations are declining and the species is listed as “vulnerable” by the IUCN. Climate change is a big factor – as temperatures rise, white-tailed deer are moving further north and taking over areas that are typically occupied by reindeer. Beyond taking resources like food, these deer are also bringing a worm parasite that will kill reindeer that contract it. Warmer summers also mean more insects, which can harass reindeer enough that they fail to put on the weight they need to in order to survive the winter. Beyond climate change, humans are also directly changing reindeer environment through development, oil exploration, and recreational activities like snowmobiles. As the Arctic continues to warm and as humans continue to disturb their native habitat, reindeer will need our help to survive.
Reindeer in the snow. Image from Natalia_Kollegova on Pixabay. Image retrieved 12/22/2021

So there you have it – reindeer are cool. They are so well-adapted to their environment, between their hairy feet, hairy nose, and color-changing eyes. Hopefully through conservation efforts, they will continue to amaze us for years to come.


Further Resources

San Diego Zoo

Cool Green Science

A-Z Animals

Live Science

Orlando Science Center

Leave a Reply

%d bloggers like this: