Ms Bosiger also developed what she termed a “stone fish camera” — functioning as submerged surveillance equipment — to document the unprecedented behaviour. “I still can’t believe we got it to be honest,” she added.
Series producer Lara Bickerton became tearful upon hearing Sir David’s voiceover work for the first time, describing the experience as deeply moving given it was her initial collaboration with the broadcaster.
“It’s the first time I’ve worked with Sir David, so I did cry the first time I heard the first line of the Seasonal Seas episode,” she admitted. “That was just a dream, to be able to work with him on the show.”
Executive producer Liz White emphasised the uncertainty surrounding Sir David’s participation, noting his centenary year added particular significance to his involvement. “Obviously there was no guarantee he was going to do it, but the fact it’s his 100th year as well makes it feel so much more special to us,” she said.