Do Birds Live in Antarctica? How Reversible That Choice Is

Yes. Birds live in Antarctica. C.M. Harris, K. Lorenz and M. Syposz, in a 22 February 2017 paper to the Antarctic Treaty Consultative Meeting, list 20 bird species in the Important Bird Areas assessment for Antarctica south of 60°S, the Antarctic Treaty area. That occupancy is reversible. Most of those species treat the continent as a seasonal production line: they arrive, they breed, they leave. Emperor penguins are the hard case, an 8- to 9-month winter cycle on fast ice that the Australian Antarctic Program times from about April, and that British Antarctic Survey satellite imagery showed can fail completely when that ice breaks before chicks fledge. A snow petrel can reverse course in a day. A penguin cannot.

A cook-chill line that holds four thousand trays a day cannot pause a kettle and still serve that batch. Emperor breeding runs on the same kind of clock. The season is the batch. If the ice fails, that year's chicks are lost even if the adults return.

How many bird species breed in the Antarctic Treaty area?

Harris, Lorenz and Syposz reproduced Table 1 from Harris et al. 2015 as "a listing of the 20 bird species" breeding in Antarctica, with detailed census data for only 10 of them. The 20 names are emperor, gentoo, Adélie, chinstrap and macaroni penguins; Wilson's storm-petrel; black-bellied storm-petrel; light-mantled albatross; southern giant petrel; southern fulmar; Antarctic petrel; Cape petrel; snow petrel; Antarctic prion; imperial (Antarctic) shag; snowy sheathbill; kelp gull; Antarctic tern; south polar skua; and brown skua. The study area is south of 60°S, the Antarctic Treaty area.

Other inventories sit next to that 20 and do not match it. Hannah S. Wauchope of the University of Cambridge, Justine D. Shaw of the University of Queensland, and Aleks Terauds of the Australian Antarctic Division, in a 2019 Nature Communications assessment of ice-free Antarctica, treated 21 bird species as the vertebrate set after dropping marine and ice-breeding animals except emperor penguins. An older Antarctic Connection excerpt, later reproduced by Ornithology.com, said 35 seabird species live south of the Antarctic Convergence and 19 breed on the continent itself. The Australian Antarctic Data Centre still hosts a SCAR Expert Group on Birds checklist from May 2005: 83 species tagged breeding, visitor, or vagrant. Those four documents use different maps.

The 20-species Treaty-area list answers which birds nest in Antarctica. The 83-species SCAR list is a Southern Ocean checklist that includes birds that only pass through.

Can birds that live in Antarctica leave again?

For most species the choice is seasonal. Adélie penguins occupy ice-free coastal rock in the austral summer, then go to sea. A.J. Tree and N.T.W. Klages, in Marine Ornithology in 2004, classed Antarctic terns on the Peninsula and South Shetland Islands as non-migratory, and Indian Ocean populations as long-distance migrants that winter on the South African coast. M.J. Szabo's snow petrel account on New Zealand Birds Online, updated in 2022, reports that some birds remain at colonies year-round, with the main influx from mid-September to early November, and winter dispersal to pack ice, ice floes and open seas.

Emperor penguins reverse later than the rest. The Australian Antarctic Program's breeding-cycle page, last updated 16 May 2008 and still the Program's public account, says adults return to sea in January and February to fatten for the next season.

Flying birds reverse faster. New Zealand Birds Online, in Szabo's account, gives the snow petrel a wingspan of 75–95 cm, a length of 30–40 cm, and a mass of 200–460 g, and records nests up to 440 km inland and 2,400 m above sea level. Animalia.bio lists 76–79 cm. The 75–95 cm range is the current New Zealand Birds Online figure. A bird on that wing can leave a failed ice edge the same day. A penguin has to walk or swim.

How do penguins differ from flying Southern Ocean seabirds?

Penguins and flying seabirds share krill, fish and squid. They do not share an exit.

| | Emperor and Adélie penguins | Fulmarine petrels (snow petrel, Antarctic petrel, southern fulmar) | Skuas, gulls and terns | | --- | --- | --- | --- | | Locomotion | Swim; flightless | Flight; snow petrel wingspan 75–95 cm (New Zealand Birds Online) | Flight | | Breeding platform | Fast ice (emperor) or ice-free rock (Adélie) | Cliffs, crevices, nunataks; snow petrels to 440 km inland | Coastal rock; some terns also use ice edges after breeding | | How occupancy reverses | Emperor: 8–9 months locked to ice, then sea in January–February. Adélie: summer colony, then sea | Air: leave a failed site the same day; some snow petrels stay year-round | Antarctic tern: some Peninsula birds stay; Indian Ocean birds winter in southern Africa | | Role | Prey for skuas and giant petrels | Ice-edge foragers; prey for skuas | South polar skua: predator. Kelp gull and Antarctic tern: fish and krill |

South polar skua sits in both columns of a food web: it breeds in the Treaty area, flies, and takes penguin eggs and chicks as well as petrels. Southern giant petrel scavenges and kills. Wilson's storm-petrel, in the Harris 2015 IBA table drawing on Brooke 2004, has a global estimate of 12–30 million individuals, the widest band on that list. Light-mantled albatross is on the same table as Near Threatened, with an A1 threshold of 10 pairs. Most albatross breeding lies north of 60°S; the birds still forage over the Southern Ocean. Penguins reverse a colony only by swimming to other ice or rock. Flying birds reverse a site by leaving.

When do emperor penguins breed, and what happens if the ice fails?

The Australian Antarctic Program times the start to autumn, around April, once fast ice is thick enough to hold thousands of birds. The female lays a single egg; in late May or early June she leaves for the sea and the male incubates. The Program gives 65 to 75 days to hatching, with females returning in July. By early December chicks are near adult size and begin growing waterproof feathers. In January and February the birds go to sea.

Other clocks sit beside that page. A 2024 Nature Communications paper on emperor abundance and breeding success reported birds returning between late March and early May, an average incubation of 64 days, and hatching between July and August. The United States Fish and Wildlife Service restates an 8- to 9-month season that needs fast ice from arrival through chick rearing. Fretwell, Boutet and Ratcliffe, in Communications Earth & Environment in 2023, described stable fast ice from about April until chicks fledge around the end of December. The sources agree on the shape of the year and disagree on incubation: 65–75 days on the Program page, 64 days as an average in the 2024 study of two intensively watched colonies.

The 2022 Bellingshausen Sea season showed what happens when the hold fails. Peter T. Fretwell, Aude Boutet and Norman Ratcliffe of the British Antarctic Survey used Sentinel-2 imagery and reported that four of five sites in the central and eastern Bellingshausen Sea suffered total breeding failure after sea ice broke up before fledging. The five colonies, named Rothschild Island, Verdi Inlet, Smyley Island, Bryan Coast and Pfrogner Point, ranged from around 630 pairs at Rothschild Island to around 3,500 pairs at Smyley Island; chicks fledged at Rothschild Island. Fretwell, a geographer at the Survey, told reporters the team had never seen emperor penguins fail to breed at that scale in a single season, and that sea-ice loss during the Antarctic summer made survival of displaced chicks very unlikely.

The adults can try again. Michelle LaRue, a remote-sensing ecologist discussing Landsat records of Smyley Island with NASA Earth Observatory in 2026, said one bad breeding year, even a total failure, does not mean the end of a colony. The site choice can reverse. That year's production cannot.

How large are Adélie penguin colonies, and do they stay put?

Heather J. Lynch, then at Stony Brook University, and Michelle A. LaRue, then at the University of Minnesota, published the first global Adélie census in The Auk in 2014. They estimated 3.79 million breeding pairs (95th-percentile confidence interval 3.52–4.10 million) in 251 breeding populations, with first figures for 41 previously unsurveyed colonies (420,000 pairs) and 17 previously unknown colonies, 11 of which may have been recent colonizations. They reported 13 colonies not found, including 8 concluded extinct. Peninsula declines were more than offset by East Antarctic increases. The 3.79 million figure was 53 percent larger than Woehler's 1993 estimate of 2.47 million pairs.

Later compilations do not copy that number. Harris, Lorenz and Syposz, in the 2017 Treaty paper, compiled 4,004,200 Adélie pairs and noted that Southwell and colleagues, then in press, suggested closer to 4.75 million pairs. Oceanites' State of Antarctic Penguins 2024 lists 4,325,253 nesting pairs for 2024, up 113,362 (2.69 percent) from 4,211,891 in 2022. Those four figures—3.79 million, 4.00 million, 4.33 million, and about 4.75 million—are estimates of the same species taken by different methods in different years.

Lynch and LaRue's 8 extinctions and 11 possible new colonizations are a line that can be shut and, sometimes, reopened on another rock. Peninsula decline against East Antarctic growth is a shift of the batch, not a continent-wide halt.

How far does an Antarctic tern actually migrate?

Antarctic tern (Sterna vittata) is not Arctic tern (Sterna paradisaea). Mixing the two is the usual error on this question.

Tree and Klages, in Marine Ornithology 32: 55–61 (2004), described Antarctic tern as a winter visitor to stretches of the Western and Eastern Cape coasts of South Africa, arriving in May, peaking in July and August, and mostly gone by the end of October. Their Table 5 classed Antarctic Peninsula and South Shetland breeders as not long-distance migrants, South Orkney breeders as migrants, and Indian Ocean populations (Prince Edward, Crozet, Kerguelen, Heard) as migrants. New Zealand Birds Online says New Zealand Antarctic terns do not undertake the long migrations of Arctic terns and often remain close to the breeding islands.

Heard Island birds are the distance case. Australia's SPRAT profile for Sterna vittata vittata, citing E.J. Woehler 2006, infers a route between Heard Island and southern Africa. The Australian Antarctic Program's Heard Island FAQ, last updated 28 February 2005 and still posted, puts Heard Island "about 4700 kilometres from South Africa to the north west." William E. Davis Jr., in a 2007 Pacific Conservation Biology note, wrote that the island lies "3 750 km from Africa." The 4,700 km and 3,750 km figures disagree. Neither is a geolocator track of an individual tern. SPRAT itself says the route is inferred.

Arctic terns have been tracked. Carsten Egevang and colleagues, in Proceedings of the National Academy of Sciences in 2010, reported an average 70,900 km a year (range 59,500–81,600 km) from Greenland breeders. Ruben C. Fijn and colleagues, in Ardea in 2013, reported Dutch birds at a mean 90,000 ± 2,000 km including staging. Those figures describe a different species that winters in Antarctic pack ice and then flies north. Using either number for Antarctic tern is a citation that will not survive a check.

What did the 2025 winter sea-ice maximum mean for birds?

On 17 September 2025, Antarctic sea ice reached a winter maximum of 17.81 million square kilometres (6.88 million square miles), according to the National Snow and Ice Data Center at the University of Colorado Boulder. NSIDC's 30 September 2025 analysis ranked that maximum third lowest in the 47-year satellite record, 740,000 square kilometres above the 2023 record low as then stated, and 900,000 square kilometres below the 1981–2010 average maximum. Extent was markedly below average in the Indian Ocean and the Bellingshausen Sea, and slightly above average out of the Ross Sea.

NSIDC's 3 October 2024 release gave a 2024 maximum of 17.16 million square kilometres and a 2023 record of 16.96 million. The 2025 analysis table lists 2023 at 17.07 million and 2024 at 17.26 million, both asterisked. The 2025 winter figure of 17.81 million is the named-season number; the earlier rows moved after reprocessing.

Ted Scambos, senior research scientist at the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder, said of the 2025 maximum: "The lengthening trend of lower Antarctic sea ice poses real concerns regarding stability and melting of the ice sheet. However, it may also be leading to greater snowfall over the continent, which would slow the progression of sea level rise."

Summer minima sit on a separate clock. NSIDC put the 1 March 2025 minimum at 1.98 million square kilometres, tying 2022 and 2024 for second lowest, with 2023 still the record at 1.79 million on 21 February. Four consecutive summers below 2.0 million square kilometres is the run Fretwell's emperor work is watching. Emperor chicks need fast ice into December. Adélie penguins need ice-free rock in summer and pack ice to forage. Snow petrels, on Szabo's account, feed mainly in water with 10–50 percent ice cover. A winter maximum 900,000 square kilometres below the 1981–2010 average is a shorter hold on the line.

FAQ

Do any birds live in Antarctica year-round?

Emperor penguins stay on the coast through an 8- to 9-month winter cycle that the Australian Antarctic Program times from about April. New Zealand Birds Online notes that some snow petrels remain at colonies year-round. Most other breeders leave after summer. Even emperors go to sea in January and February to fatten before the next hold.

Are there flying birds in Antarctica or only penguins?

Flying birds breed there. Harris, Lorenz and Syposz's 2017 IBA table includes snow petrel, Antarctic petrel, Wilson's storm-petrel, south polar skua, kelp gull and Antarctic tern alongside five penguin species. New Zealand Birds Online gives the snow petrel a 75–95 cm wingspan. Penguins dominate photographs; they do not monopolize the list.

How many bird species breed in Antarctica?

Harris, Lorenz and Syposz list 20 breeding species south of 60°S in their 2017 paper to the Antarctic Treaty Consultative Meeting. Wauchope, Shaw and Terauds counted 21 bird species as the vertebrate set in a 2019 Nature Communications assessment of ice-free Antarctica. An older Antarctic Connection excerpt said 19 breed on the continent itself.

Why do emperor penguins breed in winter?

The Australian Antarctic Program times the cycle from about April so chicks fledge in midsummer, when food is easier. Females lay in late May or early June; males incubate 65 to 75 days and hatch in July. If the ice breaks before December, as Fretwell's 2022 Bellingshausen observations showed, that year's chicks are lost.

Do Antarctic terns migrate as far as Arctic terns?

No. Indian Ocean Antarctic terns winter in southern Africa. The Australian Antarctic Program puts Heard Island about 4,700 kilometres from South Africa; William E. Davis Jr. wrote 3,750 km from Africa in 2007. Arctic terns tracked by Egevang and colleagues averaged 70,900 km on the annual circuit. New Zealand Antarctic terns often stay near the breeding islands.

Can a penguin colony come back after the ice fails?

Adults can return. Michelle LaRue, discussing Landsat records of the Smyley Island emperor colony after 2022, told NASA Earth Observatory that one bad breeding year, even a total failure, does not mean the end of a colony. Chicks from a failed season do not survive. The site can be reused; that year's production cannot.