Rock monkeys have long been a scourge of coffee farmers in Taiwan's mountains because they eat the ripe berries and spit out the seeds.
But now, the farmers now realize the simians are actually doing them a good turn and are avidly collecting these half-chewed seeds. For the coffee made out of those seeds tastes sweeter and demand is increasing for that variety all over the island.
"The monkeys pick the reddest fruits to eat, and spit out the seeds. They cannot swallow them because that may cause indigestion," said Liao Ching-tung, a coffee farmer for 30 years and who has recently taken up roasting the regurgitated seeds.
"For other crops it may cause serious loss, but if they eat coffee in this area, then it saves me the trouble of peeling the fruits," he added.
Liao says the discarded seeds yield a sweeter coffee with a vanilla-like scent, which sells for about $56 a pound (450 grams).
For coffee lovers like Wang Chih-ming, price is no object.
"I like coffee it's got a nice aftertaste, that's really good," said Wang.
Coffee beans excreted by native civet cats in Indonesia and painstakingly extracted by hand from the animals' forest droppings reputedly produce the world's rarest and most expensive coffee, which sells for around $1,000 a kg ($450 a pound).