The park was proclaimed in 1972 under National Parks and Wildlife Act 1972 replacing earlier protected area status as a Fauna Conservation Reserve which was proclaimed in 1967. The protected area status exists to protect the island as a breeding area for sea birds such as little penguins and silver gulls.[4]
Pullen Island Conservation Park has a moderate climate with an average temperature of 15 °C and an average rainfall of 766 milimeters per year. The warmest and driest month is December (22 °C with 22 milimetres of rainfall). The wettest and coldest month is June (8 °C with an average rainfall of 142 millimetres).