Zookeepers in Indonesia have been forced to move an orangutan out of visitors' reach after it developed a serious smoking habit.

Tori learned to smoke 10 years ago by imitating zoo visitors, who would throw their cigarette butts into her open cage. She has been smoking ever since, according to activists. They say she holds up two fingers to her mouth to indicate she wants a cigarette and becomes angry and throws things if none are readily available.

Keepers at Taru Jurug zoo in Solo have unsuccessfully tried luring the ape away with food and extinguishing the butts with water.

Now the zoo, with help from the Borneo-based Centre for Orangutan Protection (COP), plans to move the 15-year-old primate and her partner to a small island on the premises by August. They hope the large trees, rope swings and views over the facility will make Tori forget about her nicotine fix. Until then, the centre has sent extra volunteers to guard the cage and will install mesh netting to prevent visitors from throwing in their butts.

Tori may be Indonesia's most famous smoking orangutan, but she is not the only one. The animal's parents were also smokers and many more of Indonesia's zoo-based orangutans are thought to be hooked on the habit, says Hardi Baktiantoro of COP. The creatures' 97% genetic similarity to humans means that they will often mimic and take on behaviours similar to ours – sometimes to their detriment.

"It is very common in Indonesian zoos for people to throw cigarettes or food [at animals] even though there are signs to not feed or give cigarettes," says Baktiantoro. "It happens all the time. [In Tori's case], people will throw cigarettes in, watch her smoke, start laughing and take pictures."

So far, Tori's partner, Didik, who is new to the zoo, has not yet taken up smoking, preferring instead to stamp out butts whenever they are thrown into the cage he and Tori share.

But activists worry that he could soon succumb to the habit, as nearly 70% of Indonesian men over the age of 20 are smokers, and zookeepers have had difficulty preventing visitors from smoking on the premises.

Indonesia's zoos have come under fire for their conditions – where visitors, not just zookeepers, are sometimes to blame. It was reported two years ago that, at Surabaya zoo in East Java, about 25 of its 4,000 animals were dying prematurely every month. This included a Sumatran tiger and an African lion.

In March this year, a 30-year-old giraffe was found dead at the zoo with an 18kg (39.7lb) ball of plastic in its stomach, after years of eating litter thrown into its pen by visitors.