In response, the orca have started eavesdropping on other herring-hunters.

From miles away, they have learnt to tune into the noise of fishing machinery.

A trawler'’’s winch is like a dinner bell.

The fishermen work at night when the herring rise up from the deep.

The nets are already full but the orca are patient.

As the catch is hauled aboard any strays and spills are easy pickings.

There'’’s not enough to satisfy a humpback so the orca feed undisturbed.

Well...

Almost!

Auden has caught up with the orca.

Their presence around the trawlers gives him the perfect opportunity to delve deeper into their changing world.

"What we want to do is to follow constantly" " and see what they do" " to do that you have to have a tag on" " a satellite tag."

"These are going to report positions" "for hopefully up to three months" "So then we can follow the herring" "and can see if these killer whales" "are following the same pattern as the herring."

"Ok " "Ok " "Let'’’s get it on."

"The bird hit me in the face!"

"This is totally madness."

Success will take patience and skill.

"Tag on!"

"Yes!

Yes!"

"High five!"

"Mission completed!"