Sims Island (Antarctica) IBA | Summary

AQ203

Sims Island

Current view: Summary

Country/territory: Antarctica
IBA Justification: A4iii (2015)

Area: 70 hectares (0.70 km²)

Site description (2015 baseline)

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.

Key biodiversity
The IBA was designated based on 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).

Subsequent to IBA designation, an expedition in January 2022 noted the following:

From direction observation: there were 3000 (+/- 50%) pairs of nesting Adelie Penguins. This record was also reported to the MAPPPD database. A database hosting population records for Antarctic penguin species.

Estimate of roughly 200 South polar skuas.

Snow petrels are confirmed breeders on the island

Weddell seal haul-out on the island ("lots" sighted)

The only form of vegetation found was the typical land algae (Presiola Crispa).

No traces of lychens or bryophytes. (Unless covered by snow).

Short dive close to the island on the western coast between 7-11meters depth noted: thecosomate pteropod, comb jellies, nacella concinna limpets, amphipods, nototheniid fish, monostroma hariotii (green algae), variety of red algae, odontaster validus (seastars)

Crabeater seals were also swimming around in the waters around the island.

Recommended citation
BirdLife International (2025) Important Bird Area factsheet: Sims Island (Antarctica). Downloaded from https://datazone.birdlife.org/site/factsheet/sims-island-iba-antarctica on 07/01/2025.