6/14/2017 10:16:16 AM
Learning How the Other Half Lives
I warmed my numbed nose with thickly-gloved hands as the helicopter’s rhythmic thumps faded in the distance. I had been dropped off rather unceremoniously on a pan of sea ice to lessen the machine’s weight during its upcoming maneuvers. I carried only the essentials with me: survival food, sleeping bag, and shotgun. The ice beneath was slowly being moved by the ocean’s powerful current—very slowly, I hoped anxiously. My drop-off location had been marked by a GPS point that would be used to find me again before taking me to the tranquilized polar bear that I would soon fit with its own GPS technology—and I didn’t want to drift too far off course.
Filling a Polar Bear Knowledge Gap
This spring, for the first time ever, our team researched polar bears directly on the sea ice of Hudson Bay, the habitat they depend on for survival and that is changing rapidly due to climate warming. We followed regular procedures like tranquilizing bears from the helicopter, assessing their body condition, and taking standard measurements like skull width and body length; we also used new technology to fill a long-standing knowledge gap. While we’ve been studying the Western Hudson Bay population of polar bears for decades, we still don’t know where and how half of them travel on the sea ice. This year, that was going to change.
In April 2017, Polar Bears International provided support for a new Sea Ice Ecology Project in western Hudson Bay, led by Dr. Andrew Derocher of the University of Alberta. For decades, a sampling of female polar bears in this area have worn GPS collars. The devices supply scientists with data about where and when the bears move, how they use sea ice, how they find seal prey, and how they manage all of this with and without cubs. Such information is critically important to know about an animal whose habitat is changing fast, yet we know little about the male and subadult (age 3-5 years) polar bears in the population. This is because adult males have necks thicker than their skulls, allowing them to pull GPS collars off; and subadults grow quickly, so the collars don’t fit well for long.
Subadult, male, and female polar bears lead very different lives on the sea ice. Yet, until recently, there were few ways to know about what the males and subadults do when they leave the land to hunt.
New Ear Tag Data
Finally, new technology is helping researchers monitor the movements of the entire population. In the fall of 2016, Manitoba Sustainable Development’s Polar Bear Alert team put small GPS-linked ear tags for the first time on 16 adult male polar bears. The bears had temporarily been kept in a holding facility for coming too close to the town of Churchill, Manitoba and were soon released farther north with their new tags. The ear tags submitted GPS locations for up to six months, providing scientists with the first data on the movements of male bears in the region. Even more important, the transmitted locations helped keep people safe.
Learning about the movements and behavior of male and subadult polar bears will help fill critical knowledge gaps. Photo copyright BJ Kirschhoffer/Polar Bears International.
Polar bears and people share coastlines across the Arctic. As climate change causes sea ice to break up earlier and freeze up later, polar bears are spending more time on land, where they are more likely to encounter communities. GPS tags can act as a warning system, allowing wildlife managers to intercept a bear before it gets too close to a village. Using technology to monitor polar bears during these changing seasons can prevent unnecessary human contact in the short term and help us predict movement patterns as sea ice declines in the long term. The ear tags help paint a picture of the animals’ movements, but this information alone won’t help conserve polar bears.
Polar bears need our help now: Hudson Bay’s polar bears could disappear this century if we don’t change our energy habits. To conserve polar bears, we must protect their sea ice habitat by reducing greenhouse gas emissions. Burning fossil fuels traps excess heat in our atmosphere, which melts sea ice. And less sea ice equals less food for polar bears, who rely on the ice for reaching their seal prey. A societal shift to cleaner energies like solar and wind, technologies we already know and use, will benefit polar bears by protecting their habitat, but will also help people. People and polar bears don’t just share coastlines, we share the planet.
While one team member kept an eye out for polar bears, two others examined the remains of a recent seal kill—the sign of a successful hunt. Photo copyright Jon Talon.
We fitted ten more polar bears (seven adults and three subadults) with GPS ear tags this spring and will continue to put out the tags each fall and spring for at least the next 3-5 years. While the ear tags are expensive, the information they provide will be invaluable for science. We will know more about how successful the bears were at hunting this winter when they return to land this summer. Until then, we will monitor their GPS locations, keep them out of communities, and hope they grow fat before the ice breaks up.
As I heard the helicopter returning, my anticipation overrode any anxieties. I love contributing to important research projects, whether in the field or behind a computer, and working with inspiring people on exciting projects to help keep polar bears in the Arctic forever is well worth my frozen nose.
Our thanks to Banrock Station Wines and the SeaWorld & Busch Gardens Conservation Fund for their generosity in helping to support this study. We’re also grateful to the Point Defiance Zoo and Aquarium for supporting the purchase of GPS ear tags.