Feeding time is the best time to glimpse our group of free-ranging white-faced sakis. They faithfully turn up at the Treetops Trail exit at 10.30am and 2pm for the feast laid out for them. Carrots, apples, primate pellets and rice balls with sweet potatoes and egg are part of the spread. Treats like sunflower seeds, peanuts and mealworms are given on occasion. The daily feeding sessions condition the free-roaming sakis to stay within their designated area.

Male sakis are black except for the white ‘face mask’ that surrounds their face and the species is named for their striking appearance. Females are mostly brownish-grey, with two vertical stripes from their eyes to the corners of their mouth. When they’re young, males and females look similar. Males start to gradually don the ‘white mask’ at 3 to 4 years of age.

Sakis move through the forest on all fours and by leaping. Their long bushy tail, which is about the length of their body, is not prehensile but helps them keep their balance. When escaping from danger, they can make downward leaps covering close to 10m, a feat which has earned them the nickname “flying monkeys”. Wholly arboreal, the sakis seldom, if ever, come down to the ground, though they may descend to the lower limbs of trees or even to bushes in search of food.

Sakis are partial towards seeds, spending 95-99% of total consumption time on breaking them open and eating them. To drink water, sakis soak their hands in water and lick them. Equally peculiar is their bedding down posture - they curl up on branches like a cat! They typically spend the night in larger trees in the canopy that provide good cover.