[4] When looking at individuals within this species, the most defining characteristic is the warty yellow caruncle found on the forehead.

The wings of this species are extremely strong and are powerful in flight with continuous wingbeats disrupted by some gliding.

[2] However, the IOC World Bird List and the Clements Checklist consider the Antarctic shag to be its own species.

[3] The Antarctic shag is described as a marine species staying near the shores of coastal regions and some islands.

However, a single Antarctic shag was found dead in Bahia, Brazil in 2002; it had previously been ringed in the South Shetland Islands.

[8][9] Colonies may move short distances to find waters that aren't frozen in order to feed.

This short move most likely occurs during winter months when ice starts to spread and cover the ocean where the birds feed.

Still, recent studies using Unmanned Aerial Vehicles (UAV) have allowed scientists to estimate Antarctic shag populations by taking images of colonies.

[10] In 2018, a study found that 3.5% of the global Antarctic shag population breeds in Ryder Bay.

[2] Sometimes, breeding colonies are shared with other bird species such as the rock shag, southern rockhopper penguin, and black-browed albatrosses.

[4] The naked chicks are fed by their parents for about 3 weeks with the male partner providing most of the food.

[4] Breeding success can be directly affected by food availability[3] and diving conditions.

[4][2] Most of the Antarctic shag's diet is composed of fish,[13] but can also include crustaceans, octopuses, snails, worms, slugs and other invertebrates.

There have been a few documented cases, including leopard seals and brown skuas killing Antarctic shags.

[16] Thus, the Antarctic shag links the benthic and pelagic zones of the food web.

[13] Shags can't predict how much time is required to dive and capture prey.

If a fish is found but the shag doesn't have enough oxygen, it will come back up to the surface, take in the largest amount of air possible, and dive again to capture the prey.

This shows that the Antarctic shag changes its diving strategy based on the situation.

Additionally, birds having to spread their wings to dry could have further reduced their body temperature in an already extremely harsh climate.