00:00 Foods, particularly that they were getting when they were on land, have pretty low caloric
00:06 content, and the bears have to expend energy to obtain them.
00:10 So out on the sea ice, they're primarily a sit and wait predator, and they're eating
00:15 primarily the fat of seals, which has twice the calories of protein and carbohydrates,
00:21 which is what they are primarily getting when they're on land.
00:25 Similarly, when they were swimming out into the bay and encountering carcasses, we found
00:29 that it was difficult for them to eat those carcasses while they were swimming, and they're
00:34 getting a single carcass over a three-week period versus catching seals every few days
00:41 out on the sea ice.
00:42 So it's just a big difference in the availability and quality of the food resources they can
00:47 get when they're on land.
00:49 All of the bears we studied, that we tracked in this study, were in relatively good condition.
00:55 There are no bears that we consider to be in poor condition.
00:59 With the caveat being that the time period that we conducted this study was basically
01:04 right in the middle of the time that they're on land.
01:07 So as I mentioned, they typically come on land around late July, early August.
01:14 We did this work in late August to early September.
01:18 And so they still have another 70-so days on land where they will be continuing to lose
01:24 mass.
01:25 I think our study confirms previous evidence that they're not very adaptable to spending
01:32 time on land.
01:33 That there's going to have to be other changes that would have to occur that are going to
01:37 help them withstand spending longer times on land.
01:42 One of the things that was really appealing to me was the fact that it's a very elegant
01:47 study in that they combine many different techniques to study a question about what
01:53 is happening in this population relative to the increasing length of the ice-free period.
02:02 So for me, I think it's a combination of physiology, behavior, and looking at the movements of
02:09 the animals.
02:10 And of course, the video colouring is a very nice addition.
02:14 So it gives you a better complete picture of what the animals are doing in that environment.
02:20 So one thing that would have been very nice to see would have been mothers with cubs included
02:25 in the study.
02:27 Partly because some of the research in my group is indicating that that is a very vulnerable
02:32 link in the population.
02:35 And so our concern is that once mothers with cubs lose their body condition to a certain
02:41 point, they stop producing milk.
02:44 And all of a sudden at that point, the cubs now have to rely on their own fat reserves.
02:49 And cubs in their first year in particular are growing rapidly, have very little stored
02:54 fat of their own.
02:56 And we think that this is probably one of the major weaknesses in the population ecology
03:01 of the bears.
03:03 And so if the mother doesn't get them back out on the ice and feeding on seals shortly
03:07 after she stops nursing, we've seen this in Western Hudson Bay, where the cubs actually
03:13 starve to death on land.
03:15 And so that point might have been nice to have included, but it also adds another level
03:21 of complexity.
03:22 And then you get into ethical issues of handling mothers with small cubs.
03:26 And because you have to handle them more than once, it does present some animal care challenges
03:32 for sure.
03:33 [BLANK_AUDIO]
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