“What we have done to the deep ocean floor is just unspeakably awful,” said Sir David.
“If you did anything remotely like it on land, everybody would be up in arms,” he said in the interview released on Saturday. It was conducted at the premiere of his new documentary, Ocean, last month.
The documentary draws attention to the potential damage from some fishing practices, like bottom trawling, for marine life and the ability of the ocean to lock up planet-warming carbon.
Governments, charities and scientists will come together at the UN Oceans Conference (UNOC) in Nice to try and agree how to accelerate action on the issues most affecting the world’s seas.
Sir David said he hopes the leaders gathering for the UN conference will “realise how much the oceans matter to all of us, the citizens of the world”.