The number of pilot whales that have died following a mass stranding in New Zealand has reached nearly 500.
Officials are putting the current number of deaths at 477, which occurred on two remote beaches on the Chatham Islands, around 500 miles east of New Zealand's main islands. The remote location hindered attempts to refloat some of the whales, as did the potential presence of sharks in the surrounding waters.
These deaths were in addition to the 200 pilot whales that became stranded and died a couple of weeks ago on a remote Australian beach.
New Zealand has one of the highest number of stranding incidents with pilot whales often involved. Pilot whales can strand in large numbers as they live in very tight social groups and, when a lead individual has made a navigational mistake or one of the group is sick or wounded, the rest of their pod frequently follow that individual towards the shoreline and into trouble. It is thought that the long sloping beaches in some regions cause navigational errors.