Monkeys better tone down their 'business', or else some states in India might put them on the pill.
The most commonly seen Indian monkey, the Rhesus Macaque, can charm some but can be a pain for others with their marauding ways, belligerence and lack of fear of humans.
They are not often violent, but they do eat farmers’ crops, ransack homes and harass humans in their quest for a meal.
Clashes between monkeys and humans are on the rise in Uttarakhand and Himachal Pradesh, according to government officials. As a result, the two states are considering fertility drugs to combat the problem.
"No crops are growing because these monkeys are taking it all. They are increasing in numbers, troubling farmers," Himachal Pradesh Forest Minister Thakur Singh Bharmouri told Al Jazeera.
India banned exporting monkeys for biomedical research in 1978. The country used to be the world’s largest exporter of monkeys. Since then, the country has had trouble with their burgeoning population. Rampant urbanisation encroaching on their habitats has added to the problem.
The lush northern states of Himachal Pradesh and Uttarakhand have been particularly vulnerable to conflicts with monkeys as jungles invariably adjoin farmlands.
Himachal Pradesh has already performed more than 68,000 vasectomies on monkeys since the state started the country’s first sterilisation programme in 2006.
Officials estimate there are about 300,000 monkeys in the state, all of which they aim to sterilise.
Should such drugs be considered as one tool to address monkey overpopulation, the plan would be to approach this cautiously by conducting safety and efficacy trials before considering widespread use
Government employees in several parts of the state either capture the monkeys or pay Rs 500 (about $8) as bounty to people who catch and bring them to centres where they perform the operation.
They are then released.
But while the number of monkeys has reduced, the situation is not improving, said Bharmouri.
Monkeys are getting more aggressive and the forest department is looking for other ideas, he said, adding "progress has been made but I still need to protect people".
Both Himachal Pradesh and Uttarakhand are working with an advisory organisation, the Wildlife Institute of India (WII), on ways to control the number of monkeys.
The institute has recommended that Uttarakhand also start performing vasectomies, and that both states research the feasibility of anti-fertility drugs, among other ideas.
"We are still looking at all the material. We need to find out how to deliver them [anti-fertility drugs]. Also, how do we identify the individuals we’ve already given it to?" PC Tyagi, a landscape management specialist at the WII, told Al Jazeera.
"They need to make a feasible plan."
Tyagi could not specify what type of drugs could be used and emphasised that the idea is still in its early stages.
The states must also keep a record of how many monkeys there are and where they live so they can analyse and keep track of the impact, he said.
Researchers at the California National Primate Research Center are also working with the WII and the Indian government to help resolve the human-monkey conflict.
The center says fertility drugs have not been extensively tested on non-human primates.
But Brenda McCowan, the center’s programme leader, said the contraceptive, porcine zona pellucida, administered by an injection, has worked well with horses and deer.
"Should such drugs be considered as one tool to address monkey overpopulation, the plan would be to approach this cautiously by conducting safety and efficacy trials before considering widespread use," McCowan said.
[Sterilisation] will simply result in breaking up families so that more people are attacked. It will also result in a large number of monkey deaths
Wildlife officials in the capital of New Delhi are also interested in sterilising monkeys because they say relocation efforts to a local sanctuary are not working.
Delhi struggles with employing monkey-catchers who are supposed to bring the animals to the wildlife sanctuary where officials say some 20,000 of them are fed daily. Wildlife officials also say the monkeys are expensive to feed and they do not stay in the sanctuary, often returning to their places of origin.
While contraceptives could be effective, animal activists say existing procedures are not carried out properly.
Himachal Pradesh has been under fire because the sterilisations have resulted in hundreds of monkey deaths, either from poor capturing conditions or untrained veterinarians.
Uttarakhand has looked into performing vasectomies in the past, but the state was confronted with vast opposition and did not follow through with the plans.
Member of Parliament and prominent animal rights activist Maneka Gandhi doubts the effectiveness of sterilisation, vasectomies and contraceptives.
"It may remove reproductive ability, but will it stop them from coming into the cities for food? No," she told Al Jazeera.
"It will simply result in breaking up families so that more people are attacked. It will also result in a large number of monkey deaths."
McCowan, however, said the center has more than a decade of experience studying macaque behavior and that if done properly, contraception could be a positive solution.
"Such an approach would be used to compliment the already robust efforts of the monkey sterilisation programmes," she said.