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SPEED limits for ships could help save the endangered northern right whale,
according to marine biologists.

David Laist of the Marine Mammal Commission near Washington DC and his
colleagues examined 30 reports of dead right whales washed up on the east coast
of the US between 1975 and 1996. They found that 10 of them probably died from
collisions with ships, suffering major bone fractures and propeller lacerations.
And this may be an underestimate, Laist suggests, as casualties do not always
reach the shore.

Right whales are the most endangered large whale, with a population of fewer
than 300 animals. Laist says that slowing ships to below 14 knots in an area 20
miles off the coast of Georgia and Florida could halt the decline in whale
numbers. Females congregate here from December to March to calf.

The researchers also looked at records of collisions between ships and whales
dating back to 1877. They found that collisions were comparatively rare when
ships were travelling between 10 to 14 knots. At these speeds the whales had a
chance to get out of the way, says Laist. 鈥淚n four or five seconds, a whale
could move four or five body lengths at least.鈥� At slow speeds, the bow waves of
large ships may also help to push whales clear of the vessel鈥檚 path.

Hal Caswell of Woods Hole Oceanographic Institution in Massachusetts points
out that collisions with ships are one cause of whale mortality that people can
reduce. At current death rates, he has predicted that the North Atlantic right
whale will become extinct within 200 years
(New Scientist, 20 March 1999, p 4).
Since then he has worked out that preventing the deaths of just two
females a year could prevent that decline. 鈥淓ach death is pretty important in a
population that small,鈥� he says.