''Ours specialise in hunting for rays,'' Visser said. ''It's quite unique behaviour.''
Read More: Orca alert: National Geographic team in Northland to film orca
Read More: Orca experience 'awesome' on Northland harbour for siblings
This is the optimum month for orca sightings, she said. Unfortunately, weather conditions were rough so water visibility was limited for filming purposes, despite several sightings of orca.
''We have had no luck with the weather in combination with seeing orca.''
During the film makers' stay, sightings came in to the Orca Research Trust from the South Island and the Auckland and Far North regions, but being in the same place at the same times as the animals proved a hard task.
One day last week Visser got a call at 6am — and the convoy of film crew and spotters was on the road by 6.05am, en route to Mangonui Harbour and a short while later to Taipa.
The team spent a while looking but couldn't find the orca, ''and then the real bad weather kicked in so we had to give up".
The crew of six have now finished their stint but Visser is hopeful they'll be back.
''They were amazing, there was an Emmy Award winner, they're incredibly prestigious filmmakers. It was an honour and a privilege to work with them and share our wonderful stories, and we learnt such a lot from them too,'' Visser said.
''They are absolutely enamoured with the New Zealand orca, and they've got good enough footage. They did film some activity.''
What the crew also got was some unique storytelling about individual orca, their relationships, personalities, culture and history.
''We've got 30 years of history with these animals and we can tell their life stories. We know these animals.''
Four New Zealand-based underwater camera operators will continue filming orca, ''to see if we can get the ultimate behaviour to add''.
The documentary will appear in a four-programme series on whales on the National Geographic Channel in 2020. Each hour-long programmes focuses on a different whale species.