"He might have change his mind in the 19 years between the papers."

Wrong again, g. From a 2012 review by Stirling and Durocher:

Abstract
Climate warming is causing unidirectional changes to annual patterns of sea ice distribution, structure, and freezeup. We summarize evidence that documents how loss of sea ice, the primary habitat of polar bears, negatively affects their long-term survival. To maintain viable subpopulations, polar bears depend on sea ice as a platform from which to hunt seals for long enough each year to accumulate sufficient energy (fat) to survive periods when seals are unavailable. Less time to access to prey, because of progressively earlier breakup in spring, when newly weaned ringed seal young are available, results in longer periods of fasting, lower body condition, decreased access to denning areas, fewer and smaller cubs, lower survival of cubs as well as bears of other age classes and, finally, subpopulation decline toward eventual extirpation.