Five dolphins have washed up dead after what rescuers called a “highly unusual” stranding event in the Highlands.
More than 50 bottlenose dolphins were trapped on the coast near Nigg Sands on the Cromarty Firth.
Volunteer marine mammal medics from the British Divers Marine Life Rescue (BDMLR) monitored the scene on Saturday morning.
The dolphins had been stranded in shallow water at low tide but because of their distance offshore, the dangers presented by rapidly changing tides and a sandbar rescuers could not get to them.
A few hours later the rising water refloated the creatures but they did not swim off.
At first light on Sunday, the dolphins were found even further into the Cromarty Firth and were even tracked past Invergordon.
A spokesperson for BDMLR said there was a lot of concern that they might re-strand at the Cromarty Bridge.
After hours of monitoring the situation, pod was eventually turned around and left into the wider Moray Firth.
But five of the bottlenose dolphins were found washed up dead in the area.
“Needless to say, this is a highly unusual stranding event for this species, the likes of which we have not encountered before,” a spokesperson for the charity said.
“We would like to thank all of our team at BDMLR who were involved on the scene and behind the scenes who were dealing with this situation through the weekend, and to the staff at Scottish Marine Animal Strandings Scheme as well as the local Coastguard rescue team who provided support throughout.”
The animals have been retrieved for post mortem examination by the Scottish Marine Animal Strandings Scheme.
It is hoped further investigation will shed light on the reasons for the incident.
BDMLR said the dolphins were not thought to be members of the Moray Firth’s resident population and were instead part of an offshore group.