Search for Sound of Canna's rare marine life
Marine biologists have returned to the Sound of Canna to resume surveys in to the presence of some of Scotland's most important wildlife.
The species, described as priority marine features (PMFs), include fan mussels, burrowing sea anemones, northern sea fans and seagrass.
The isle of Canna lies off the coast of Skye.
Survey work started in August 2010 and this summer's research will probe how far fan mussels have extended north.
Marine biologists from Scottish Natural Heritage started the latest survey last week aboard research vessel Sir John Murray.
It is owned and crewed by the Scottish Environment Protection Agency.