Sims Island is a small ice free island of ~1.5 km by ~0.8 km situated south of Smyley Island and about half-way between Case Island and Rydberg Peninsula in Caroll Inlet, Bellingshausen Sea.
The IBA qualifies on the basis of the concentration of seabirds present (in particular Adélie Penguin (Pygoscelis adeliae)) and comprises all of Sims Island.
Sims Island is of volcanic origin. The southern coast is dominated by cliffs rising up to 380 m and a small beach on the northeastern coast provides the only flat ground on the island (Hathway 2004).
Convey et al. (2011) suggested the island may possess habitat suitable for vegetation communities, although this needs to be confirmed by ground survey.
There are no research stations nearby. The closest permanent stations are Rothera (GBR) and San Martín (ARG), located approximately 710 km to the northwest in Marguerite Bay, Antarctic Peninsula.
Approximately 14 784 breeding pairs (95% CI: 8888, 24 254) of Adélie Penguin were present on Sims Island as estimated from December 2012 satellite imagery (Lynch & LaRue 2014). The penguins breed along the beach on the northeastern coast of the island. This colony was reported for the first time by Lynch & LaRue (2014), and it is unknown how long the colony has existed. South Polar Skuas (Catharacta maccormicki) breed on the island, but numbers are unknown (Convey et al. 2011). No other birds are known to breed in the area.
Non-bird biodiversity: None known.
BirdLife International (2019) Important Bird Areas factsheet: Sims Island. Downloaded from http://www.birdlife.org on 19/07/2019.