22 June 2012
Slowest Greenland sharks hunts sleeping prey
By Victoria Gill
Science reporter, BBC Nature
Researchers have measured the swimming speed of the ocean's slowest shark.
Data-logging tags revealed that Greenland sharks "cruise" at 0.34m per second - less than 1mph.
The study showed that, even when the languid fish embarks on a burst of speed in order to hunt, it is far too slow to catch a swimming seal.
Since the species is known to eat seals, the scientists think it probably "sneaks up on them" as they sleep under the water.
The Greenland shark was already known to be the world's slowest swimming shark, but its sluggishness surprised the scientists.
Yuuki Watanabe from the National Institute of Polar Research in Tokyo, who took part in the study, said that, when you account for the size of its body, it is the slowest fish in the ocean. (...)
Full article: http://www.bbc.co.uk/nature/18531924