Bertie Gregory's Image

Bertie Gregory (UK) tracks a pod of orcas as they prepare to wave wash a Weddell seal.

This pod belongs to an ecotype known as B1 - the pack ice orcas -identified by their characteristically large, white eye patches. These orcas are known for hunting seals using a method known as wave washing.

To spot a seal at rest on an ice floe, the orcas spyhop by poking their heads above the surface. They then charge towards the ice, creating a large wave that washes the seal into the water where it has little chance of escape. The bubble streams the orcas produce during wave washing are thought to aid communication, enabling the team to synchronise their high-speed manoeuvres.

‘This is a spectacular and record-setting view of this rarely seen behaviour,’ says Melissa Groo, Wildlife Photographer and Competition Judge. ‘You can empathetically feel the vulnerability of the seal in the face of the power and size of the orcas, and the tension of this moment, which seems about to explode into action and predation.’

Bertie undertook two month-long expeditions off the Antarctic Peninsula searching for B1 orcas. ‘We spent every waking minute on the roof of the boat, scanning,’ he says. After battling high winds and freezing conditions, Bertie captured this remarkable behaviour with his drone.

The B1 population is rare, numbering only about 100, and is thought to be declining by about 5% each year. Not only this but the behaviour of wave washing might disappear as melting ice floes due to rising temperatures force seals to spend more time on land.