Neil Nightingale writes
Steve Hewlett's piece Is It OK For Natural History Programmes to Use Fake Footage? gives a false impression of both the motivation for and our openness about filming animals in controlled conditions. He also suggests this is done for "entertainment". While the great majority of our footage is filmed entirely in the wild there are some animals and natural behaviours that are virtually impossible to obtain in the wild. If we did not sometimes film in controlled conditions we would be unable to bring these fascinating stories to audiences. It is for reasons of enlightenment and education that these techniques are necessary.
See Neil's letter in full here
You also might be interested in how open some productions really are about their studio filming. We can find out al about Wild China's filming techniques online where they give clear reasons for the use of non-wild clips.
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