Greenpeace drops boulders in North Sea to block bottom trawling

Greenpeace activists aboard the ship Arctic Sunrise have dropped giant boulders into the Southern North Sea marine protected area to snag the nets of industrial trawlers. The site is the UK's most bottom-trawled protected area, and the group says the underwater barrier aims to stop the destructive practice and help conserve porpoise populations. Greenpeace has declared the zone an 'ocean park'.