Humans do, monkeys do more.
That is why a group of volunteers has decided to tackle the simian problem facing Bukit Timah homes at the source. Since a few weeks ago, the new Bukit Timah Wildlife Network has been urging visitors to the nature reserve there not to feed the monkeys.
The aim is to prevent the animals from getting overly acquainted with human food and being fed, which emboldens them to approach residences.
Last year, The Sunday Times revealed how the authorities increased culling efforts after a rising number of resident complaints about monkeys getting into their homes.
According to the Agri-Food and Veterinary Authority (AVA), it euthanised about 570 long-tailed macaques last year, and another 100 so far this year.
This is a third of the estimated islandwide population of around 2,000 monkeys.
The culling appears to have been effective. AVA said there have been 420 complaints about monkeys so far this year, compared with 1,860 last year and 920 in 2012.
Mr Balasupramaniam Krishna, the neighbourhood committee chairman of Mayfair Park, a private estate of 1,000 homes in Upper Bukit Timah, also said he gets just one complaint a month now, compared with four to eight last year.
But the deaths of so many monkeys worried some residents, researchers and animal welfare groups.
Ms Sim Ann, Minister of State for Education and Communications and Information, and one of the MPs for Holland-Bukit Timah GRC, said that the monkey issue has been "a vexing one" for her area. Many residents complain about the animals, yet others are upset about the culling, she said.
"Even though residents may disagree over what to do about the monkeys... on both sides (they) tend to agree that public education remains very important," she said, adding that a "multi-pronged" approach is still necessary.
Under the new network, led by the Bukit Timah Community Club Youth Executive Committee, about 40 residents, students and others will spend weekend mornings at the Bukit Timah Nature Reserve approaching and educating visitors.
One volunteer, Hwa Chong Institution student Joanne Ong, 17, said that in her experience, macaques were unlikely to approach people unless they were enticed.
Ms Sabrina Jabbar, campaign executive at the Animal Concerns Research & Education Society (Acres), said that the root of the problem is at the reserve.
"That's where the monkeys get used to human food and they start to venture out. So if we can control this... it will gradually improve the situation," she said.
Added Ms Sim Ann: "The idea is to, over time, reset human and monkey interactions in the nature reserve."
This article was first published on August 17, 2014.
Get a copy of The Straits Times or go to straitstimes.com for more stories.