Wings do not guarantee flight. You may think that the ability to fly might be one of the most envied and useful aspects of being a bird. However, there are numerous bird species which, through evolution, have lost their ability to fly over time.
This has happened in different bird groups independently, meaning that flightlessness is a
good example of convergent evolution. This is when distantly related organisms evolve the
same or similar traits in response to similar pressures and needs.
But why might flightlessness be useful? In some cases, it is because flight simply isn't needed, due to a lack of predators for example, and so it is more beneficial to direct resources into other abilities.
This is why flightless birds are often found on isolated islands. In other instances, flight apparatus might even be a hindrance, making it more difficult to dive deep into the water for instance.
Giving up on flying also allows birds to become much larger and heavier - it’s no coincidence that the world’s largest bird, the common ostrich, is flightless. Read on to learn all about 10 of our favourite flightless birds.
10 flightless birds
Inaccessible Island rail (Laterallus rogersi)
This curiously named species is the world’s smallest flightless bird. Endemic to a South Atlantic
island with the very on-the-nose name of Inaccessible Island, this tiny brown bird only reaches a
maximum length of 15.5cm and a maximum weight of 49g.
One big mystery about this species is how they got to the remote island in the first place. It was initially thought that they had always been flightless, and so scientists theorised that they must have walked over now long-submerged land bridges.
However, with a greater understanding of plate tectonics, alongside genetic evidence, the truth of their past has recently been revealed. Genome sequencing has suggested their closest living relative is a flighted bird (the Dot-winged crake), meaning that the common ancestor of these two had the ability to fly, and the ancestors of Inaccessible Island rail likely simply flew to their island home.
Common Ostrich (Struthio camelus)
From the smallest to the largest, the next on our list is the ostrich. This sizeable bird is in fact
both the heaviest and tallest of all extant birds (let alone just flightless ones). Adult males can
stand up to 9 feet tall and weigh over a whopping 24 stone!
Contrary to the popular myth these birds don’t stick their heads in the sand when scared and are instead likely to run away.
As obligate ground nesting birds they do however sometimes put their heads in their sandy nests to
rotate their eggs, which is probably where the myth originated.
Kakapo (Strigops habroptila)
The next on our list is perhaps one of the strangest birds that exists. Not only is it the world’s
only flightless parrot, but it is fat and bright green, often moves around by jogging, is nocturnal,
and is also very friendly to humans!
Unfortunately, these bizarre New Zealand natives are critically endangered. It is thought that the arrival of predatory cats and rats (brought by European colonisers) was responsible for the sharpest declines, and by the mid-1900s kakapos teetered on the very edge of extinction with only a few individuals left. Recent intensive conservation efforts have brought them back from the brink, however. As of 2023, there are now 247 individuals surviving.
Emperor penguin (Aptenodytes forsteri)
Perhaps the best-known examples of flightless birds are penguins. Penguins' wings have
become supremely adapted for swimming rather than flying. The emperor penguin is the largest
of all penguin species, standing at a stately 120cm tall on average.
They are only found in Antarctica, living in vast colonies of up to around 20,000 pairs on the sea ice. This social living is one of the ways they keep from freezing once the brutal Antarctic winter descends. To stave off the cold males (who are left caring for their chicks whilst their mates are feeding at sea), huddle
together in tight-knit groups, shuffling so that everyone gets a turn in the insulated middle of the huddle.
Kiwi (Apteryx genus)
This bizarre and beloved bird is the national animal of Aotearoa New Zealand. I know what you
may be thinking - which came first, the fruit or the bird? Well, the furry fruit was actually named
after the bird and not the other way around!
The name Kiwi is thought to have come from the Māori language and is derived from the call that they make. Kiwis are very unusual birds. Not only are they flightless but they also have quite a few almost mammalian traits. Instead of being hollow like most birds, their bones are heavy and marrow-filled. They are also born fully feathered and independent, and their shaggy plumage is almost hair-like.
They have a highly developed sense of smell and are the only birds to have nostrils at the end of their beak.
Takahe (Porphyrio hochstetteri)
Another flightless New Zealand bird is the colourful Takahe. These stout birds are the largest
living rail species, weighing up to 3.8 kg (a far cry from the diminutive Inaccessible Island rail).
Takahe are somewhat of a conservation miracle, having been thought extinct for nearly 50
years and then famously rediscovered in an isolated valley in 1948.
Their decline was due to extensive hunting by the native Māori people, but also competition and predation from non-native mammals introduced by European settlers. Today they are extensively protected and managed and their population is around 500 individuals and growing yearly.
Darwin's rhea (Rhea pennata)
In the same group as ostriches (ratites), Darwin’s rhea are similarly long-necked and long-
legged. They are however considerably smaller, standing only about 3 feet tall. They a
prodigious runners, reaching top speeds of 37 mph as they dash across their South American
grassland home.
The name, quite predictably, is after the famous naturalist, who is said to have eaten one during his voyage to Patagonia! Halfway through the meal he realised this was a species he had been searching for and was able to put together a nearly complete specimen from the remains to bring home.
Fuegian steamer duck (Tachyeres pteneres)
Something you might not expect to see on a list of flightless birds is a duck! One of only a few
flightless duck species (including 3 of the 4 steamer duck species) the Fugeian steamer duck
inhabits rocky coastlines and islands in Chile.
These handsome but hulking ducks are particularly aggressive and are known to kill other, even much bigger, bird species for no apparent reason. They use their tough spurred wings to deal deadly blows to those unfortunate enough to stray into their territory during mating season.
Flightless cormorant (Nannopterum harrisi)
The only cormorant that has lost the ability to fly, this appropriately-named bird is found only on
the Galapagos Islands. It is a good example of the unusual animals found on this incredible
archipelago.
Living on an isolated island with no natural predators and taking most of its food from diving into the sea meant that the ability to fly became less important. In fact, for a diving bird flight feathers can be a hindrance, as air bubbles get trapped in them. And so these cormorants eventually evolved smaller and less obtrusive wings.
Titicaca grebe (Rollandia microptera)
This very sweet-looking bird is found, as the name would suggest, primarily on Lake Titicaca on
the border of Peru and Bolivia. Although completely flightless this species does however utilise
wing-assisted running, flapping its wings to help it cover large distances with ease.
They are also excellent divers, spending much of their time beneath the surface hunting fish.
Unfortunately, these charismatic birds are classified as endangered, with the greatest threat
they face being caught up and drowning in gill-nets