This short clip (click to watch in a new window) from a forthcoming episode of the new BBC documentary series, Human Planet, shows the Inuit people of Kangiqsujuaq, near the Hudson Strait, venturing underneath the winter sea ice to harvest mussels. As the narrator explains:
This settlement and a neighbouring community on Wakeham Bay are thought to be the only places where people harvest mussels from under the thick blanket of ice that coats the Arctic sea throughout the winter.
The locals can only do this during extreme low tides, when sea ice drops by up to 12m (about 40 feet), opening fissures through which the exposed seabed—and its edible riches—can be glimpsed.
The cameraman captures the Inuit hunters lowering ladders into the gorgeous blue-green caverns with their carpet of mussels left behind by the retreating tide. Crawling underneath the massive, unstable chunks of ice, they have just half an hour to fill their buckets and find their way back to the surface, before the sea returns. And, in a detail that brings home how dangerous these expeditions really are, the narrator explains that although a look-out keeps watch as the water flows back inland, "warning shouts cannot be too loud in case the echoes bring down the ice."
More clips and schedule details are available at the BBC's website; h/t to Pruned for the link.