Here's How You Can Tell if a Reindeer Is Pregnant

Slate’s animal blog.
April 3 2014 12:20 PM

How Can You Tell if a Reindeer Is Pregnant?

img_9256
A reindeer gets an ultrasound. Don't worry—she was fine.

Courtesy of Helen Fields

In a snowy valley on the island of Spitsbergen, 500 miles north of mainland Norway, a reindeer is getting a pregnancy test.

She's lying in the snow, grumpily. One leg has been popped out of the hobble that ties her other three legs together, and she has already used it to kick snow on me, the ultrasound machine, and veterinarian Erik Ropstad, who chuckles.

Advertisement

Spitsbergen is the largest island in the archipelago of Svalbard—no, it wasn't invented for the children's fantasy book The Golden Compass; it's a real place, with real polar bears. I spent a week there this time last year to report on a long-term study on reindeer for Smithsonian magazine.

Every spring since 1995, a few British and Norwegian scientists have been going to Svalbard to chase reindeer. They stay in a tiny cabin on the edge of vast, white Reindalen—Reindeer Valley. There's no running water but plenty of beer, box wine, and Scotch.

Each day they go out on snowmobiles to look for reindeer they've tagged in past years. They use binoculars to pick out an animal with collar and ear tags, usually high up on a hillside, send a snowmobile or two to herd it down to flat land, then chase it with a big net.

The idea is to understand how the numbers of reindeer change over the years—are there more? Fewer? What causes the ups and downs? They tag only females; if you want to understand how a group of animals is expanding and contracting, you really need to know about fertility.

Thus the pregnancy test.

Ropstad pulls the bottle of ultrasound gel out of his snowmobile suit where it has been staying warm against his body—reindeer don't like cold gel on their skin any more than humans do—and squeezes it on the probe, then holds the end of the probe to her nipple, the only piece of bare skin on a reindeer. Conveniently, it's right next to the uterus.

With bright white snow below, bright white mountains on either side, and bright white sky overhead, the screen looks like a solid piece of black glass. The solution to this problem is low-tech: an old blue sleeping bag to cover Ropstad's head and the screen so he can see the images. I join him under there.

There's a lot of stuff gurgling and swishing inside a reindeer's belly, so it takes an experienced eye to pick out a moving fetus among them. “The baby,” he says, pointing out its beating heart with one hand as he moves the probe with the other. I'll take his word for it—as far as I'm concerned, it could be a bit of rippling gut or an errant vole. "Pregnant, live!" he calls to the guy writing down the numbers on a data sheet.

The scientists' analysis suggests that what really harms Svalbard reindeer, in this changing world, is rain in winter. It dribbles through the snow and freezes on the ground like Magic Shell on a bowl of ice cream. Except it doesn't taste like chocolate and it can be inches thick, too much for the animals to paw through to get at the vegetation below. In bad years, animals go hungry and few are pregnant. It had been a good winter for the reindeer; not much rain fell. Nearly every female deer they caught that week was fat and pregnant.

This week the scientists are out chasing the reindeer again, for the 20th time, to find out how they made it through this year's warm, sometimes rainy winter. While North America was getting blasted by the polar vortex this winter, Northern Europe was freakishly warm. As the scientists chase down reindeer and look at their innards this week, they'll be finding out if fewer adorable baby reindeer will be joining the population this summer.

Helen Fields is a freelance science writer in Washington, D.C. She writes about whales, meteorites, poop, and whatever else comes to mind. Follow her on Twitter.

TODAY IN SLATE

Politics

Talking White

Black people’s disdain for “proper English” and academic achievement is a myth.

Hong Kong’s Protesters Are Ridiculously Polite. That’s What Scares Beijing So Much.

The One Fact About Ebola That Should Calm You: It Spreads Slowly

Operation Backbone

How White Boy Rick, a legendary Detroit cocaine dealer, helped the FBI uncover brazen police corruption.

A Jaw-Dropping Political Ad Aimed at Young Women, Apparently

The XX Factor
Oct. 1 2014 4:05 PM Today in GOP Outreach to Women: You Broads Like Wedding Dresses, Right?
Music

How Even an Old Hipster Can Age Gracefully

On their new albums, Leonard Cohen, Robert Plant, and Loudon Wainwright III show three ways.

How Tattoo Parlors Became the Barber Shops of Hipster Neighborhoods

This Gargantuan Wind Farm in Wyoming Would Be the Hoover Dam of the 21st Century

Moneybox
Oct. 1 2014 8:34 AM This Gargantuan Wind Farm in Wyoming Would Be the Hoover Dam of the 21st Century To undertake a massively ambitious energy project, you don’t need the government anymore.
  News & Politics
Politics
Oct. 1 2014 7:26 PM Talking White Black people’s disdain for “proper English” and academic achievement is a myth.
  Business
Moneybox
Oct. 2 2014 8:07 AM The Dark Side of Techtopia
  Life
Quora
Oct. 2 2014 8:27 AM How Do Teachers Kill the Joy of Reading for Students?
  Double X
The XX Factor
Oct. 1 2014 5:11 PM Celebrity Feminist Identification Has Reached Peak Meaninglessness
  Slate Plus
Behind the Scenes
Oct. 1 2014 3:24 PM Revelry (and Business) at Mohonk Photos and highlights from Slate’s annual retreat.
  Arts
Brow Beat
Oct. 2 2014 8:47 AM Season 2 of The Bridge Was Confusing, Bizarre, and Uneven. I Loved It.
  Technology
Future Tense
Oct. 1 2014 6:59 PM EU’s Next Digital Commissioner Thinks Keeping Nude Celeb Photos in the Cloud Is “Stupid”
  Health & Science
Bad Astronomy
Oct. 2 2014 7:30 AM What Put the Man in the Moon in the Moon?
  Sports
Sports Nut
Oct. 1 2014 5:19 PM Bunt-a-Palooza! How bad was the Kansas City Royals’ bunt-all-the-time strategy in the American League wild-card game?