 Cook had earlier (25 January 1769) written of the Three Brothers hills west of Cape St Diego, so perhaps he was inspired by them too.North Brother Mountain (Dooragan) supports a wide range of vegetation communities – including some of the best examples of old growth blackbutt forest in the area and pockets of sub-tropical rainforest – that provide habitat for gliders, bats and koalas.The park has a weed problem with the spreading of lantana.