Kakapo's surprising sexual exploits (plus video)

An X-rated video of a kakapo and a zoologist has become an internet sensation.

More than half-a-million people have watched the clip on the video-sharing site YouTube which features 12-year-old Sirocco attempting to mate with zoologist Mark Carwardine.

Mr Carwardine and author-actor Stephen Fry travelled to Whenua Hoa/Codfish Island, near Stewart Island, earlier this year to film a programme for the BBC Two series Another Chance to See on the endangered parrot.

The two-minute clip shows Sirocco, who is not part of the breeding programme on Codfish Island, circle the zoologist before jumping on the back of his head.

In the clip, Sirocco is removed by a Department of Conservation ranger after his over-zealous affection caused cuts to the back of Mr Carwardine's head.

The BBC series features threatened species, and was inspired by the best-selling book Last Chance to See, which Mr Carwardine wrote almost 20 years ago with Douglas Adams, and featured the kakapo.

For the first time in decades, the kakapo population broke through the 100-mark this year, with 124 kakapo.

Department of Conservation spokeswoman Nic Vallance said the documentary, which screened in the United Kingdom last week, had helped to boost the profile of the flightless parrot.

Not only a hit on YouTube, Sirocco has more than 2000 friends following his progress on the social networking site, Facebook, and also delivers regular updates on the website Twitter.

Ms Vallance said Sirocco's amorous overtures were long known by Doc staff.

Shunning other kakapo, Sirocco turned his affection to staff members every breeding season.

His preference for humans was due to him being hand-raised as a chick, she said.

Staff often reported being "ambushed" by the budding Don Juan as they walked from their hut to the outside toilets.