Robot submarine
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Mini robot sub looking for shark food

A "hidden larder" for sharks and whales has been discovered off the west coast of Wales by a pioneering marine robot.

The high-tech mission involved sending an unmanned glider to an area around 50 miles (80km) south west of Milford Haven, called the Celtic Deep.

The glider travelled 372 miles (600km) in 30 days, undertaking nearly 3,000 dives to the seabed, at a depth of 100m (328ft).

Data from the robot shows a previously hidden plankton concentration around 30m (98ft) below the surface.

Here is footage of the robot submarine when it was first launched last summer - and a representation of what it hoped to find.

  • 20 May 2016
  • From the section Wales
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