Thursday, April 22, 2010
By Geoff York

Although far from clear, sunny, or warm, the weather is definitely improved when I look outside around 7 AM. After a little breakfast, I head up to our makeshift office and we make a plan to launch around 10 AM. Today we will head around 120 kilometres to the northeast.
The large lead (area of open water in the sea ice) that existed just offshore from our camp has closed overnight. The ice in the Chukchi Sea is very dynamic, even in the middle of winter. This part of the Chukchi is always ice free in the summer, so everything we are flying over and working on is first year or newer ice and typically not much more than 2 metres thick. Leads are constantly forming and closing and as the season winds to a close next week, the ice should really start to fragment and simply begin melting.

So why are we up here capturing, sampling, and applying satellite tracking devices to polar bears? As I mentioned in an earlier blog post, the Chukchi is one of the largest and least understood of all the Arctic’s polar bear populations. The US Fish and Wildlife Service and Russian authorities share joint management of this population along with Native peoples both in Alaska and in Russia. The last significant research in this region occurred more than a decade ago and there are pressing management needs for current data on this population, to help work out how many bears are out here, and how healthy they are.
This is essentially a pilot study to assess the feasibility of conducting a larger population estimation project. Along the way the FWS is gathering key life history and individual health data as well as information on where and when the bears move, and what places they use the most. This information will help scientists and managers to better understand how this population uses the Chukchi Sea and surrounding areas throughout the year – key for determining critical habitat and mitigating potential impacts from increasing shipping and other human pressures.
This year the FWS team is also trying a new type of tracking device for polar bears, SPOT ear tags. WWF helped provide some key startup funding for development of these less invasive tags during the 2009 season and they are now in use by both the FWS and US Geological Survey in Alaska. The tags last up to one year and provide GPS quality location data. Their use will greatly expand our knowledge of polar bear movements around the world as they can be used on all sex and age class of bears older than 1 year. Traditional satellite collars are typically only deployed on adult females. So stay tuned as FWS begins to analyse this new and exciting data stream!
It does not take long before we find our first bear, and he has literally just finished a successful hunt on a large adult bearded seal. We watch as he quickly drags the seal back towards the water – this is a seal that weighs around 182 kilogrammes! This large male quickly decides the helicopter is more of a concern than his prey and begins to saunter away from us. The area he’s in is fairly broken ice and smaller pans, so we patiently nudge him in the direction of a suitable capture spot not too far away. He cooperates, but is in no hurry.
The capture operation goes smoothly and we are soon on the ice working up a 504 kilogramme male bear in very good condition. This guy has likely been around a female and another male as he has fresh cuts on his shoulders and neck as well as two canine puncture wounds to his head, common for large males during breeding season. The wounds are superficial and will heal quickly, joining the other old scars on this bear.
The winds are calm on the ice and it actually feels relatively nice for a change. It’s the perfect situation, and the perfect bear for Greg Marshal to film both for National Geographic and to document field methods for the FWS to use in training and community outreach. He’s a real pro and manages to get the footage without slowing down the operation.
In a little over an hour, we are once again in the air and searching for another polar bear. A significant logistic factor in this part of the world is aircraft fuel. There are no fully equipped airports out where we need to operate and so we have to rely on a small airplane to bring fuel to us on the ice. Lately, the weather has made this impossible as our plane is based a long from us down in Kotzebue. We are working with Arctic Air Alaska, and today, pilot Bob Eubanks is weathered in, so we are on our own and need to start heading back.
Once again, we encounter the all too common bonus bears as we search back towards the base. This time it’s a sow with a yearling and we have just enough fuel to do the capture and make it back home. Once again we have to take great care in positioning the animals as water is an increasingly common hazard. And why are we worried about water? Polar bears in this part of the Arctic seem to seek out water, any water, as a safe haven when under stress – and capture definitely qualifies. The last thing we want to deal with is a drugged bear getting into the water and being at risk of drowning.
Fortunately, they are adjacent to a nice large pan of ice and we soon have the pair sleeping safely on the ice together. Both the mother and the yearling appear in good condition for this time of year. He’s a male and weighs 111 kilogrammes, much larger than the yearlings I am used to in the Beaufort Sea. Male polar bears in the Chukchi are thought to be among the largest in the world, in large part due to the high productivity of this region. It takes us nearly two hours to completely sample the two bears and fit the mother with a tracking collar. We lift off and take a good look around to make sure there are no curious males in the vicinity before we head back to camp for the night. We have a lot of wet gear to clean and dry before heading out again in the morning!
WWF International Arctic Programme polar bear specialist, Geoff York, is currently in the Chukchi Sea area with the US Fisheries and Wildlife Service, conducting research into the status of polar bear populations in the area, and is blogging for the WWF Climate blog while he is there.