|Most recent IBA monitoring assessment|
|Year of assessment||Threat score (pressure)||Condition score (state)||Action score (response)|
|2008||medium||not assessed||not assessed|
|For more information about IBA monitoring please click here|
Pedra Branca is the southernmost island in Australia, lying 26 km south of Whale Head in the Southwest National Park. The IBA also includes the nearby small Eddystone and Sidmouth Rocks. Pedra Branca is a rocky island with steep slopes on its eastern and western sides which rise to a north-south aligned central ridge. The key seabird species nest on tiered rock platforms and sparsely-vegetated cliff ledges of the island. Nest mounds of 270 pairs of Shy Albatross are interspersed with nests of Australasian Gannets, numbers of which have increased by approximately 7% per year from about 1000 pairs in 1978 to a congested 3317 pairs in 1995. Other seabirds are restricted to sites on unsuitable lower ledges that are affected by sea and weather conditions. Australasian Gannet numbers at nearby Eddystone Rock have also increased in recent decades from 20 pairs in 1947 to 189 pairs in 1998, when all suitable habitat was occupied.
Fairy Prion, Pacific Gull, Kelp Gull and Black-faced Cormorant breed in very small numbers. Silver Gull numbers increased from 10 pairs in 1978 to 52 pairs in 1990, with most nests located on rocks and overhangs where Pedra Branca Skinks are most abundant.
Non-bird biodiversity: Silver Gulls are believed to be responsible for declining numbers of the endemic Pedra Branca Skink, of which fewer than 400 individuals survive. Up to 500 Australian Fur Seals are regular and New Zealand Fur Seals visit occasionally. Sarcocornia quinqueflora, which is sparse and confined to rock cracks, is the only plant species recorded for the island.
BirdLife International (2021) Important Bird Areas factsheet: Pedra Branca. Downloaded from http://www.birdlife.org on 24/01/2021.