Ice thaw may leave polar bears hungry

A thaw of sea ice floating on the Arctic Ocean last year sent extra plant food to exotic creatures on the deep sea floor in a shift that might leave polar bears hungry at the surface, scientists said. The study, using robot submarines down to 4,400 metres deep, could be a glimpse of radical changes for life in the sunless depths of the Arctic Ocean after ice thinned and shrank to cover a record low area in September 2012. Scientists found large amounts of algae growing on the underside of the ice last year, apparently because more light was getting through as it thinned in a trend blamed on global warming, according to the study in the journal Science. Much of the algae, of a type that forms strands up to a metre long, then sank to the seabed where they were food for brittle stars, which are related to starfish, and tube-like sea cucumbers that grow up to about five centimetres long. “For surface life it could be bad news, for the deep sea floor it could be a feast,” Antje Boetius, of the Alfred Wegener Institute for Polar and Marine Research in Germany and lead author of the study made on the research vessel Polarstern. If the algae keep taking scarce nutrients from surface...