Gangs of long-tailed macaque monkeys have been causing havoc in housing estates bordering nature reserves; stealing food and brawling on the streets.

"They roam the estate in groups of up to 20 - rampaging the estate and turning over dustbins," one irate local wrote to the national paper in October.

"They enter the house, open cupboards, steal food and soil the premises".

Picnics are spoiled and snacks are snatched from bags while golfers tee off. Even the British Club has armed staff with brooms to shoo monkeys away from the gourmet buffet.

"It's a very weird situation," said Sharon Chan, the National Parks official tasked with managing the macaques.

"It's not that they want to attack. They just think, if you have the food, why don't you share it? Why are you eating and not sharing? Can I have some? They cross the line".

Once the line has been crossed monkeys become invasive. Plastic bag-grabbing and people-chasing is a pattern across Asia, from Hong Kong to Penang, to Bali to Japan, Chan says.

MONKEY CULLING

Other Asian countries have set up special feeding areas for their urban monkeys, but Singapore is backing an all-out ban on monkey-feeding and stiff fines for offenders.

Eight close circuit television cameras have been installed at "hotspots" over the last year, and a record 230 people fined upwards of S$200 (US$130) for feeding monkeys.

Heavy-lidded "monkey-proof" bins -- which smart monkeys already work in pairs to open, Chan says -- have been introduced.

While no one knows how many monkeys there are -- a survey ten years ago found 850 -- some 80 monkeys are culled annually.

Misbehaving monkeys used to be rehabilitated at the island's zoo but it stopped taking in macaques in 2002 because its cages were full.

"Killing them is not the same as for other animals," Professor Peter Ng, Director of the Raffles Museum of Biodiversity said. "Even for the most hardened soul. When you look in a monkey's face, you see your face in the mirror".

"Everyday the SPCA puts down cats and dogs, every week we shoot crows and kill giant sewer rats. But with monkeys, the public make a big fuss. So what's the solution? Don't feed the monkeys. We'll be forced to shoot the monkeys if you don't stop."

HARD HABIT TO BREAK

It's a tough message for Singaporeans who have been feeding monkeys all their lives.

Whenever he gets time, 50-year old driver J.J. Jolibi buys ten dollars worth of bananas and heads for the roads by the reservoirs to feed and watch curb-crawling troops.

The self-described animal-lover has been warned twice, but isn't scared of fines:

"A fine is not very expensive," Jolibi said. "I'd feed them again. Maybe the judge will be an animal lover and give me a warning. If the judge hates monkeys, maybe he'll fine me".

Consultant Barbara Martelli, 42, who works with Chan, says stamping out feeding won't be easy, even among Singaporeans well used to a regular diet of government-sponsored education campaigns on everything from flushing toilets to speaking good Mandarin.

"It is good fun. You can't deny that it's good fun. Monkeys are sweet and funny," said Martelli.

And the habit is just as hard to break for the monkeys, she added: "Human food is extremely addictive, because of the sugar and salt and spices. It's much more tasty than forest food".

URBAN JUNGLE

While forests shrink across Asia, the stress Singapore's rapid clearances of its dense primary rainforest have put on local flora and fauna make it a "test case for disaster" Ng says.

The tiny island of 700 square kilometres (270 square miles) has lost more than 95 percent of its tropical jungle since the British arrived in 1819.

Hundreds of native animals have been lost; including the last tiger, shot in 1930. The long-tailed macaques are among 50 percent of species crammed into reserves covering only 0.25 percent of Singapore's land area.

With no countryside to buffer urban areas from the jungle monkeys can't help but transgress, Martelli says. But her success rate for convincing humans to lessen tensions is only 50:50.