Sightings of whales and dolphins from ferries have been recorded as part of a UK survey.

The 50 sightings were confirmed by the crews of three Caledonian MacBrayne ferries which took part in the first Ocean Watch survey conducted by the marine wildlife charity Orca.

The nine-day survey was part of a UK-wide initiative which saw professional mariners and volunteers carry out surveys on a number of vessels, including those provided by Scottish companies CalMac and NorthLink Ferries.

The aim of the scheme was to gather data on whale and dolphin numbers and distributions in order to combat a lack of knowledge surrounding these species in UK waters. This can then be used to determine the conservation status of the animals and the general health of their environment.

Orca Ocean Watch took place between July 25 and August 2, with 271 sightings totalling 1,939 individual animals reported. Of these, nearly 20% were made by CalMac in Scottish waters.

The Scottish routes used included Oban to Colonsay, Oban to Coll, Tiree and Barra, and Mallaig to the Small Isles services.