WATCH: Dozens of orcas hunt east of Mousa

Dozens of orcas were spotted hunting east of Mousa.

Dozens of orcas were spotted spy-hopping and spraying out their blowholes east of Mousa.

The orcas surrounded both sides of Whalsay pelagic vessel Zephyr.

Fisherman John Lowrie who captured both day and night-time footage said there could have been anywhere from 50 to 100 orcas alongside the vessel.

The Zephyr are set to conclude the mackerel season today (Sunday) before returning to the sea in the New Year.