O.K. I do not think the polar bear or the grizzly subspecies of brown bear will make it to the next century…
In the case of the polar bear I really think that the specialist, ice seal predator is coming up against a changing climate and will not evolve to other foods in time to ward off such a slow reproductive rate…as ice seals go so will go the wild polar bear.
The grizzly brown bear …groups like the seemingly successful Yellowstone grizzly will go the way of most Island-like, small populations and blink out as intolerance faces the bear and climate change wipes out important food sources like the Whitebark Pine Nut…and our intolerance of this behavior, irrascable, (at times), ranges from Wyoming to Central British Columbia and all of Alberta, now.
For grizzly brown bears and polar bears I see their glass as half full.
I do not know enough about other brown bear subpopulations to comment on them but from my read on those subpopulations I suspect bad news for those bears also.
I would call this a sad situation…it is indeed sad!!!