Birnie Island is a small, uninhabited coral island, 20 hectares in area, part of the Phoenix Island group, that is part of the Republic of Kiribati. It is located about 100 km SE of Kanton Island and 90 km WNW of Rawaki Island, formerly known as Phoenix Island. It lies at 03°35′S 171°33′W / 3.583°S 171.550°W. Birnie island measures only 1.2 km long and 0.5 km wide. There is no anchorage, but landing can be made on the lee beach.
The island is designated as the Birnie Island Wildlife Sanctuary. Kiribati declared the Phoenix Islands Protected Area in 2006, with the park being expanded in 2008. The 164,200-square-mile (425,300-square-kilometer) marine reserve contains eight coral atolls including Birnie Island.
Birnie Island is low and dry, with a small, shallow lagoon in its southeast sector which is all but dried up. It is treeless, covered mostly with low shrubs and grasses, and was once home to a colony of rabbits, which have since been eradicated. Because of the undisturbed nature of the island, its vegetation, and the large colonies of seabirds which roost there, Birnie Island was declared a wildlife sanctuary in 1975. It now forms (as of 2008[update]) part of the Phoenix Islands Protected Area, one of the world's largest marine protected area.
A expedition to carry out eradication of the population of Polynesian rat on Birnie Island was carried out in 2011.
Birnie Island, Day Beacon in Background
Birnie Island Day Beacon with Lagoon in Background