The television presenter said that humans are threatening their own existence and that of other species by using up the world’s resources.
He said the only way to save the planet from famine and species extinction is to limit human population growth.
“We are a plague on the Earth. It’s coming home to roost over the next 50 years or so. It’s not just climate change; it’s sheer space, places to grow food for this enormous horde. Either we limit our population growth or the natural world will do it for us, and the natural world is doing it for us right now,” he told the Radio Times.
Sir David, who is a patron of the Population Matters, has spoken out before about the “frightening explosion in human numbers” and the need for investment in sex education and other voluntary means of limiting population in developing countries.
“We keep putting on programmes about famine in Ethiopia; that’s what’s happening. Too many people there. They can’t support themselves — and it’s not an inhuman thing to say. It’s the case. Until humanity manages to sort itself out and get a coordinated view about the planet it’s going to get worse and worse.”
Sir David, whose landmark series are repeated from Monday on BBC2, starting with Life on Earth, has also spoken out about the change in wildlife documentaries during his lifetime.
The 86-year-old said commentary from presenters like himself are becoming less necessary as camera work is able to tell a story.
“I’m not sure there’s any need for a new Attenborough,” he said. “The more you go on, the less you need people standing between you and the animal and the camera waving their arms about.
“It’s much cheaper to get someone in front of a camera describing animal behaviour than actually showing you [the behaviour]. That takes a much longer time. But the kind of carefully tailored programmes in which you really work at the commentary, you really match pictures to words, is a bit out of fashion now … regarded as old hat.”