What Is the Largest Flying Bird? Wingspan vs Weight

Why “largest” has more than one answer

Birds can be large in different ways, and the champion changes with each measure:

• Wingspan is the distance from wingtip to wingtip with the wings fully spread. Long, narrow wings suit gliding seabirds.
• Weight (body mass) tells you how much a bird must lift. Heavy flyers tend to be ground birds and waterfowl that fly only when needed.
• Wing area combines length and width. Broad-winged soaring birds such as condors have enormous wing areas even if their span is not the widest.

To compare fairly, it also matters whether you use an average adult or a single record bird. Records are often from one unusual individual, sometimes measured long ago with unreliable methods. Males are usually much larger than females in bustards and condors, so averages for “the species” can hide big differences.

Longest wings: the wandering albatross

The wandering albatross of the Southern Ocean has the greatest wingspan of any living bird. In colonies on South Georgia and the Crozet Islands, adults average about 3.05–3.1 m (10 ft). The longest-winged birds reliably measured reached about 3.7 m (12 ft). Older claims of 4.2 m (13 ft 10 in) or more have never been confirmed.

Despite those wings, the wandering albatross is not especially heavy. Adults usually weigh about 6–12.7 kg (13–28 lb). Its wings are long and very narrow, built for dynamic soaring over windy seas rather than for lifting a heavy body.

Other long-winged birds include:

• Southern royal albatross, almost equal to the wandering albatross, with spans up to about 3.5 m (11 ft 6 in).
• Dalmatian pelican, usually 2.7–3.2 m (8 ft 10 in to 10 ft 6 in).
• Marabou stork, often credited with a 3 m (10 ft) or larger span, though no measurement above about 3.2 m (10 ft 6 in) has been verified.

Heaviest flyers: bustards, swans, pelicans and condors

The heaviest flying birds are large ground birds. Male great bustards of Europe and Asia normally weigh about 5.8–18 kg (13–40 lb), and the heaviest verified bird, from Manchuria, weighed about 21 kg (46 lb). The kori bustard of African savannas is similar: males usually weigh 7–18 kg (15–40 lb), with a few exceptional birds around 20 kg (44 lb). Both walk most of the time and fly only when disturbed or moving between feeding areas.

Several other birds regularly weigh more than 10 kg (22 lb):

The mute swan holds a strange record: one unusually large male in Poland weighed almost 23 kg (51 lb), the heaviest weight ever recorded for a wild bird of a flying species. Experts doubt it could still fly at that weight, so the bustards keep the title. Because swans, pelicans and condors differ less between the sexes than bustards, they can match or beat bustards on average weight across all adults.

The Andean condor: the giant of the land

The Andean condor is often called the largest flying bird because it is both heavy and very broad-winged. Males weigh about 11–15 kg (24–33 lb), and the wingspan can reach about 3.3 m (10 ft 10 in). Its wide wings and long, finger-like wingtip feathers give it one of the largest wing areas of any bird, ideal for riding thermals over the Andes. Among land birds, only the marabou stork rivals its span, and the condor is far heavier.

Condors show how much the heaviest flyers depend on rising air. Flapping a heavy body takes a lot of power, so large birds glide whenever they can. You can see how rarely they beat their wings in Do condors flap their wings?

Why aren’t flying birds bigger today?

Flight sets a size limit. As a bird gets larger, its weight rises faster than the muscle power and wing area available to lift it. Very heavy birds need long runways, strong headwinds or high perches to take off, and they cannot flap for long. As a rough rule, scientists often cite a wing loading (weight per area of wing) of about 25 kg per square meter as the practical limit for bird flight.

The largest living flyers get around the problem in different ways: albatrosses use sea winds, condors use thermals and slopes, and bustards fly short distances only when necessary. Many truly huge birds, such as the ostrich and emu, gave up flight altogether.

Giants of the past: Argentavis and Pelagornis

Extinct birds were much larger than any flyer alive today. Pelagornis sandersi, a seabird known from a fossil about 25 million years old found in South Carolina, had an estimated wingspan of about 6.1–7.4 m (20–24 ft), roughly twice that of a wandering albatross. A 2014 study by paleontologist Daniel Ksepka suggested that it soared over the ocean much like albatrosses do.

Argentavis magnificens, which lived in Argentina about 6–9 million years ago, had a slightly smaller estimated wingspan of about 5–6 m (16–20 ft) but was far heavier, with estimates of about 70–72 kg (154–159 lb). It is still the heaviest flying bird known. For more on these giants and their flightless relatives, see the largest birds in the world.