An encouraging number of harbour porpoises have been spotted around the coast of Devon and Cornwall.
The number of sightings can act as a warning of marine trouble
The National Whale and Dolphin Watch said sightings had been particularly good off north Devon.
The Sea Watch Foundation, which carries out a survey every year around the UK, says several bottlenose dolphins have also been seen.
The survey included the sighting of a 20-strong pod of common dolphins near the Isles of Scilly.
The foundation says maintaining a record of the whale and dolphin population can help to provide a warning of potential problems in the marine environment.
About 28 species of whales and dolphins have been recorded in the past century in UK waters.