Seems to be a lot of whales in AK over the last few years.  They're here looking for food and they're not finding it.  A correlation should be made between the amount of food in the waters and the amount of predators seeking that food.  No herring in the ocean, small salmon runs.... Small salmon runs, seal/walrus/sea lion die offs.... No krill in the ocean, whale/salmon die offs.   Something has to give.  Too many predators after the same food.  Its similar to land animals, no rabbits/ptarmigan/grouse to eat, fox/mink/martin/wolf die off...  Cyclical would be my guess, but climate change is not helping matters.