Sir David Attenborough has spoken out against the BBC’s decision to cut jobs in its Natural History Unit. The renowned BBC division, home to programmes such as Planet Earth, Blue Planet and Springwatch, will lose almost a third of its programme-makers as part of budget cuts by the corporation.

The unit, based in Bristol, will lose 57 of its 180 staff and see £12 million sliced off its budget of £37 million. The veteran broadcaster told the Radio Times that the cuts would result in the BBC making fewer, or poorer-quality, natural history programmes.

Sir David, 81, said: “With cuts of that size, you simply can’t continue the same level of output, or if you do, you are going to replace it with something very skimpy.”

The BBC has been warned by independent producers of wildlife shows that the cuts would have “reverberations way beyond the BBC”.

Andrew Jackson, managing director of Tigress Productions, which makes wildlife shows, said the cuts would result in “the depletion of the BBC talent base”.

A BBC spokeswoman defended the cuts, saying: “The big landmark pieces and events such as Springwatch are continuing on the BBC and quality will in no way be compromised.”

Sir David made the comments days before his new series, Life in Cold Blood, about the world of reptiles and amphibians, is broadcast on BBC One.

Shot in high definition and costing about £800,000 for each episode, Life in Cold Blood is the final chapter in Sir David’s examinations of the natural world, which began in 1979 with Life on Earth.

Firsts on the programme include footage of Panamanian golden frogs waving; a rattlesnake hunting in the wild; the caecilian, a worm-like amphibian, allowing her young to feast on her skin, and a snake jumping. Planet Earth, which Sir David narrated in 2006, was a huge commercial success for the BBC, with sales to broadcasters around the world.

Sir David also explained why he does not mention God in his programmes. Sir David said: “I tend to think of an innocent little child sitting on the bank of a river in Africa, who’s got a worm boring through his eye that can render him blind.

“Now, presumably you think this Lord created this worm, just as he created the hummingbird. I find that rather tricky.”

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