The gist, from a story at discovery.com: global warming warmed polar ice and caused an iceberg the size of Rhode Island to detach near Antarctica. This iceberg plowed into land nearby and made it impossible for seals to come up for air as they normally did.

From the article:

Filming both above and below the thickened ice, Williams and her colleagues observed seals lining up to breathe at the few holes they were able to make with their front canine teeth. Lacking the energy to swim further, fights ensued in the lines, with animals lashing out at each other for access to air.

Are you happy, now? You’ve made seals attack each other! Seals! The ones that play with beach balls! Now they’re death machines!

(slow clap)