'Record numbers' of dolphins detected off west Scotland
Record numbers of three dolphin species found off Scotland's west coast were found during a survey by the Hebridean Whale and Dolphin Trust (HWDT).
HWDT said its scientists and volunteers last year recorded 2,303 individual common dolphins, 42 bottlenose dolphins and 94 Risso's dolphins.
The figures for all three species were the highest ever recorded in the Mull-based trust's annual survey seasons.
The conservation charity has been carrying out the surveys since 1994.
Dr Lauren Hartny-Mills, HWDT science officer, said: "The reasons for the high number of sightings of these charismatic dolphin species - and the broader effects on the marine environment and other species - remain unclear.
"But the intriguing findings highlight the importance of on-going monitoring and research."
Frazer Coomber, a scientist from HWDT, told the BBC's Good Morning Scotland radio programme: "It's been fantastic. We've had massive groups of 200 and 300 individuals at a time.
"The nice thing about dolphins is that often they come over to the vessel to come and have a look. They swim along at the front of the vessel and you get really close and get to see their beautiful yellow colouration.
"Dolphins are known as indicator species. They are a top predator, and if your top predator in an eco-system is doing well then that's a good sign that everything else in the eco-system is going well."