Andy Gibson, of the Yorkshire Wildlife Trust, said Sei whale strandings were very rare.
He said there had only been three strandings of this species in UK waters in the last 20 years.

The Yorkshire Wildlife Trust has noted a rise in whale sightings generally in 2011 but no-one is sure why there may be an increase in the mammals in the North Sea.

Over the summer, a pod of up to 10 Minke whales were spotted regularly off the North Yorkshire coast between Whitby and Scarborough.

Whale experts admit they do not know why there has been an upsurge in sightings and strandings. Some believe it could be due to changes in ocean currents bringing colder streams of Arctic water into the shallow North Sea.