The crocodiles wandering in back yards in Australia

The crocodile population of tropical Australia has exploded in recent decades. How are people learning to live with the creatures in their back gardens?

From behind a steel fence, a fully-grown adult crocodile - Harold, a heavyweight at 4.6m (15ft) long - peers at me suspiciously.

Despite the security, it is unnerving to be so close to such a fearsome predator, especially one that won't take his eyes off me.

But in Australia's Northern Territory, armour-plated saltwater crocodiles like Harold are thriving in creeks, rivers and swamps.

The species is back to levels not seen since hunting was banned in 1971. As the reptile population has increased, so has the threat to residents and tourists.

Attacks are on the rise. In April, a young Frenchman fought off a 2m (6.6ft) croc that had grabbed him by the head near the township of Nhulunbuy.

Tragically, there's about one fatality each year, and stories abound of near misses and spectacular close shaves.

"There are crocodiles in people's backyards," says Rachel Pearce, from the Parks and Wildlife Commission of the Northern Territory.

"We get call-outs to them walking into people's lounge rooms. Lots of people here live on creeks. They have big, open houses.

"When the rivers rise, the crocs are able to go wherever they like. Quite often they'll walk up into people's backyards looking for their dogs or different things, so they are in very close proximity with people here."

A 2m predator found wandering around a living room near Darwin was apprehended by a wildlife ranger, who leaped on to its back before it was safely removed.

The official advice for startled homeowners finding such a supremely aggressive animal by the sofa is to stay clear and not to attempt to wrestle it themselves, and report the unexpected intrusion immediately.

Then there are incredible accounts of monsters lurking in the far reaches of the outback.

"I led an expedition into a very remote area of the Territory. It's called the Fitzmaurice River, where nobody had ever driven into before," explained Mal Stewart, a veteran four-wheel drive explorer.

Cattle station people had flown over it previous to this and they told us: 'Beware, we reckon the croc in there is 30ft long (9.1m).'"

"Then this thing rose up next to us and we couldn't believe it. It appeared to be as wide as my boat was long."

The average length of an estuarine or saltwater crocodile is far more modest, yet still fearsome at between two and three metres.

About 80,000 live in the Northern Territory, and around 50,000 in Queensland and Western Australia. Scientists say their numbers are stabilising, having recovered so dramatically since the hunters were forced to lay down their rifles more than 40 years ago.

There are now as many crocs across tropical Australia as there are people in Darwin, the booming capital of the Northern Territory, where the authorities are reinforcing their efforts to protect residents and visitors.

-BBC