3/16/2015 5:00:39 AM
Polar Bears Go Wireless
When Dr. Tom Smith started the Maternal Den Study 13 years ago, the biological questions being asked were the same: What does normal behavior look like at a polar bear den site? When do the families emerge? How long do they stay before leaving for the sea ice to hunt for seals? And how do they spend their time before they depart?
Over the years, the questions haven't changed. What has changed is the way we try to answer them.
Studying polar bear families at den sites requires long, patient hours of observation to discover how the bears spend their time. In the old days, the team would camp on the sea ice and build snow blinds within viewing distance of the den. That way the team could hide behind the snow pile and watch day and night for polar bears while taking notes on their behavior. I'm told that the team learned two important lessons from those days:
- One, temperatures are very cold in northern Alaska in February
- Two, polar bears like to watch people who study polar bears
Given the extreme cold and the curiosity of the bears, the team decided to remove the human element and employ cameras to do the frozen work. Dr. Smith and his team took video cameras set in time-lapse mode and placed them within view of polar bear dens. Each videotape lasted four days and took short snippets of video every 30 seconds. The team housed the camera inside a cooler with large batteries to power it. A small light bulb kept it from freezing.
When I joined the project in 2009, I introduced HD cameras with an attached hard drive to store the recordings. After they proved successful, our team added a solar panel to keep the batteries charged, eliminating the need to replace or recharge 138 pounds of batteries every seven days. We also installed solar panels as a power source. They kept the batteries topped up and allowed our team to return home while the cameras recorded over a six to eight week period.
Back home, though, we constantly wondered about status of the bears and cameras in northern Alaska. We were curious about whether the cameras were operating correctly and whether we had managed to capture a bear on film. This pushed us to find a way to remotely access and view the cameras.
Our first hurdle was gaining access to the Internet when on the sea ice. This was no small task! After all, our study area is at 70° N latitude, making us just 60 miles (~100 Km) south of the most northern point of the United States. Also, powering radios and maintaining masts and antennas is difficult during the bitter cold of winter.
To solve this, we looked to the same technology we all carry in our pockets: cell phones. This year our team successfully deployed two wireless radios that operate on the existing cellular network that services the oil industry. The radios do not require a large antenna, making installation a breeze. Now from the comforts of home, our team can log in and make observations, note how the equipment is running, and see if any bears sightings have happened. This helps us in our study, but also paves the way so someday perhaps the general public will have an opportunity to watch polar bear families at a den.