Ask Dr. Jenn: Facts about Santa's Reindeer

Reindeer are a species of deer that live in the colder climates of the arctic tundra and surrounding boreal forests. They can be found in Russia, Scandinavia, Greenland, Canada, Alaska, and the North Pole. Some live in the wild and migrate thousands of miles every year; others are domesticated and live in herds. In North America, the term "reindeer" usually refers to domesticated herds, whereas members of the wild population are called Caribou.

Reindeer have special adaptations that help them thrive in colder climates, such as the North Pole. Their hooves are split to spread widely to help distribute their weight and make walking on snow and soft ground easier. These hooves also help make them excellent swimmers. A reindeer's coat contains many thick and hollow guard hairs that hold in heat. Their noses also have many tiny blood vessels that warm the air they breathe in before it enters the lungs.

Have you ever wondered where Rudolph gets his red nose? Rudolph was born with a rare condition that affects his cells that produce melanin, or black pigment. Rudolph's nose, hooves, and patches of his fur do not have any pigment. The lack of pigment makes the abundance of blood vessels in his nose much more visible, and his nose looks bright pink. When the temperature is freezing, his nose almost appears bright red and shiny. However, his nose does not glow, nor is it used to guide Santa's sleigh through the sky. That was just a song made up by the reindeer caretakers as they guided the herd across the frozen tundra with Rudolph by their sides. The song caught on among the school children, and " Rudolph's urban legend with his nose so bright" was born.

Did you know that the reindeer that pull Santa's sleigh are all female? We know this because of one very prominent characteristic: these reindeer have big beautiful antlers. Reindeer are the only species of deer where both male and female deer grow antlers. Male reindeer shed their antlers after the mating season ends in the fall.  Female reindeer keep their antler well into winter. You may have noticed that Santa's reindeer all still have antlers are Christmas time, which means that the reindeer that pull Santa's sleigh are female. Although Santa's herd is an equal mixture of male and female reindeer, he finds the female reindeer easier to train. Also, female reindeer have a higher body fat percentage, up to 50%, whereas males are much leaner with only 5% body fat. The larger amount of body fat keeps them much warmer as they fly through the high altitudes on Christmas Eve.

Reindeer are vegetarians. They feed mainly on grass and leaves during the summer. In the colder winter months, they dig through the snow in search of lichens, known as reindeer moss. Although grass, leaves, and lichens are their regular diet, a reindeer won't turn down a special treat of grains or fresh veggies. Santa loves cookies and milk, but if you really want to please him, leave out some carrots and oats for his Christmas Eve companions.

Finally, the question everyone wants to know is – can reindeer really fly? Reindeer can run, walk, and swim with grace, but they cannot fly unless Santa trains them. This special group of beloved female reindeer sail through the sky, flying as fast as a commercial jet. But how are they able to fly? That is a secret only Santa, and his elves know, and we are sworn to secrecy.

This question was answered by a special guest author: Dr. Holly Sparkle Paws.

Dr. Holly grew up at the north pole to a family of Scout Elves. She attended veterinary school at the Ontario Veterinary College and returned to the North Pole to provide medical care to Santa's animals, including his special herd of reindeer.