With a bright orange beak and black bandit mask plumage, it looks for all the world like a cartoon character.

An almost luminous emerald Javan green magpie raises comical, Groucho Marx eyebrows quizzically - cocking its head.

It announces its presence by barking out a loud, eclectic range of calls - from rhythmic trills of increasing pitch, to high squeaks and low, raucous squawks. Often, all are performed in combination.

The garish look helps camouflage the bird in its natural home in the rainforest. But its voice is not so discreet.

I am not watching this bird in the mountain forests of Java - its natural home, but in a high-security aviary.

Once, it had been stolen for its song.

Today, it is under lock and key in a yard patrolled by two large dogs and surrounded by a tall, spiked fence.

This is for its own protection.

No-one has reported seeing a wild Javan green magpie in its natural habitat for several years. Conservationists think the number remaining in the wild is vanishingly small - perhaps as low as 50.

The bird - a tropical relative of the crows and magpies so familiar across much of Europe - is now a poster child for what conservationists are calling the songbird crisis.

Almost 50 different species of songbirds are native to Indonesia.

They used to be a common sight, but now they are threatened with extinction, according to the International Union for the Conservation of Nature (IUCN).