Comment by hermitcrab

Found this:

"Technically, probably the hardest thing was trying to film bottom trawling because it's never been filmed before and we didn't know if it was possible. You have to film the wonder but you also have to film the destruction. Capturing that was absolutely essential and it took a lot of research to find some scientists planning bottom trawling experiments who decided that adding cameras would help their research and also help to share it with the world."

At:

https://www.arksen.com/blogs/news/ocean-with-david-attenboro...