When David Attenborough decided to make a nature programme about cuckoos he immediately called Oxford ornithologist Mike Bayliss to ask for help.

Mr Bayliss worked on the programme Cuckoo, shown on BBC2 last night as part of the Natural World series narrated by Mr Attenborough.

Mr Bayliss, 63, of East Street, Osney Island, collected bird’s eggs as a child and started studying birds in the early 1980s.

In 1988, Mr Bayliss won the cuckoo egg record when he counted 25 eggs from the same female, finally crediting her with 113 after eight more seasons.

Mr Bayliss, who previously worked with Mr Attenborough on the Life of Birds series, said: “I really enjoyed working with Mr Attenborough — he’s a very nice chap.

“A lot of the filming for the programme was done between Sandford and Radley between May to July in 2007.

“We must have done at least 150 hours of filming, watching and waiting for the cuckoo to lay her egg.

“It’s a very time-consuming process, with lots of waiting around and taking notes.

“We discovered the cuckoo chicks make such an incredible noise that the feeding rate is increased.

“I was an egg collector when I was a boy.

“Then, in the early 1980s, I got involved with a water rail survey at South Hinksey and that got me started again.”

Scientists have puzzled for years over why birds are duped into raising a cuckoo chicks.

In the programme, Prof Nick Davies, of the University of Cambridge, shows how baby cuckoos use a rapid begging call to mimic a nest full of hungry young to spur the adults into bringing extra food.

Prof Davies said: “For the first time, viewers are able to see — and hear — one of the earliest tactics that cuckoos adopt to stay ahead in what has become a feathered arms race.

“The rapid call fools the foster parents into flying back and forth with as much food as they’d bring for a whole brood of their own young, and enables the cuckoo chick to survive to start the cheating cycle all over again.

“The cuckoo has to overcome many obstacles to reproduce, and so guarantee that an iconic sound of Spring remains part of our lives.”

The programme is also scheduled to be shown on BBC2 tomorrow at 5pm.

affrench@oxfordmail.co.uk