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Footage shows a harbour seal trying to evade a pod of hungry killer whales by seeking refuge in a mussel farm off Shetland.
The seal was surrounded by eight orcas on the hunt for food north of Lerwick on 6 March this year.
Local drone pilot Nick McCaffrey captured 38 minutes of the dramatic chase, which saw the seal hide between two lines of mussel ropes at Grunna Voe farm.
It can be seen gliding in between the ropes as the killer whales edge closer, in what has been described as previously undocumented behaviour.
But the predators pounced when the seal ventured out of safety, swiftly dispatching their prey.
The footage was analysed by Emily Hague, a PhD student at Heriot-Watt University in Scotland, who is researching the impact of human activities on marine animals - including man-made structures such as fish farms and offshore energy developments.
Ms Hague said: "Interactions involving man-made structures are rarely, if ever, caught on camera.
"This makes this footage extra special and very insightful from a scientific point of view."
The film provides a "new perspective" on how marine life and man-made structures can co-exist in the sea, Ms Hague added.
"It's fascinating that these novel structures in the marine environment are potentially being used by prey to hide from predators."
The footage also sheds light on the potential risks marine animals face.
"Last year a juvenile member of this killer group died entangled in rope and was found on Orkney," Ms Hague said.
"If this group is spending a lot of time around marine structures, then this may have associated risks, like entanglement."
Mr McCaffrey captured the footage after he and fellow wildlife enthusiasts were alerted to the orcas' arrival by the Shetland Orca Sightings Facebook page, managed by wildlife photographer Hugh Harrop.
He traced the pod's route as the orcas travelled from just south of Lerwick to Grunna Voe.
Ms Hague's full findings were published on Thursday in the scientific journal Aquatic Mammals.