An 18-second clip of a Silverback
gorilla walking upright on his hind legs like a human has become a
YouTube sensation.

Almost 150,000 people have viewed the clip in just
a few days and the number is rising.

The 21-year-old named Ambam is part of a group of
critically endangered Western lowland gorillas at Port Lympne Wild
Animal Park near Hythe.

The footage was filmed by animal researcher Johanna Watson as
she worked on a project on great apes.

But as gorilla keeper Phil Ridges explains, walking on hind legs
is not a new phenomenon: "Ambam was hand raised for a few months
when he was a year old because he became very ill and as a last
resort he had to be taken away from his mother Shumba.

"He came over to Port Lympne when he was seven
or eight years old. He is our biggest gorilla at around
220kg.

"Ambam's father Bitam used to display the same behaviour if he
had handfuls of food to carry.

Video: The YouTube
footage of Ambam

"Ambam also has a full sister, Tamba, and a half sister at
Howletts, who also sometimes stand and walk in the same way. All
gorillas can do it to some extent but we haven't got any who do it
like Ambam and he is quite a celebrity at the park."

He said he thought Ambam might do it to get a height advantage
to look over the wall at feeding time.

Ambam was born at Port Lympne's sister park, Howletts, in
1990.

Both parks are dedicated to protecting rare species and are
managed by an international conservation charity called The
Aspinall Foundation (TAF).