Spending much of its time in the trees, the highland guan forages for berries and fruits, but it may descend to the ground where it has been noted eating animals, including lizards and mice. It is often seen in groups of three or four individuals, as well as singly and in pairs. Individuals call to each other with a high-pitched ascending whistle (2) (4).
Whilst pairs of highland guan are often seen together, this species is thought to be polygamous, with more females hatching successfully than males. Between February and May, a large and poorly constructed nest is built from sticks and leaves, and is lined with some of the female’s downy feathers. It is typically positioned within a tree, tree fern, or bush, sometimes near or on the ground. Two eggs are laid which hatch between March and June (2) (7) (8).