The whale is thought to be one of those injected with drugs by vets
A second, rare, northern bottlenosed whale has been found dead in the Cromarty Firth, the coastguard said.
The animal is thought to be one of two whales that became stranded in the firth, on Sunday night.
Vets administered injections to humanely kill both whales, but one swam away on the high tide.
Marine Conservationists said they expected both animals would die due to their injuries and the amount of time they spent out of the water.
A third whale appeared to have successfully made its way back to sea.
The species is the same as one which made its way up the Thames into the centre of London in 2006.