Return of Bird of the Week: Flightless Cormorant


Flightless Cormorant, Fernadina Island, Galapagos Archipaelego

There are birds that lack one of the definitive characteristics of birds: flight. The Flightless Cormorant is one example, a large cormorant and the only one of the 40 species of cormorant to have evolved away from flight. Many flightless bird species are endemics to remote islands, like the New Zealand Rail and the Falkland Island Steamer Duck. But half of the species of cormorants are confined to a single, remote island, yet only the Flightless Cormorant has abandoned the air. It’s a mystery.

The Flightless Cormorant is confined to Fernandina Island and the northerly and westerly shores of Isabela island in the Galapagos archipelago. There are believed to be about 1,000 individuals, although like many species dependent on the Humboldt and Cromwell Currents and the cold water upwellings the currents produce, Flightless Cormorant populations plunge when an El Niño shuts the currents down.

As you can see from the photo, the primary flight feathers only extend as far as the back of the thigh. As a result, the wings are useless for flight, but they do assist the bird in swimming underwater to hunt. WC was lucky enough to watch this species while snorkeling, and its underwater maneuverability is very impressive.

If you see a cormorant in the Galapagos, it’s going to be this one; if you see a cormorant anywhere else, it’s not going to be this one. That makes identification pretty easy.

Flightless Cormorant, Fernadina Island, Galapagos Archipaelego

Flightless Cormorants primarily target sea bottom prey: fish, including eels and rockfish; octopus and squid. It feeds mainly by pursuit-diving. With the Galapagos Penguin, this species triggers fishing behavior by other bird species, because the cormorants and penguins tend to force fish towards the surface.

Like many other cormorants, its systematic classification is controversial; at one time or another ornithologists have placed it in four different genera. But a consensus seems to be emerging that it’s properly a member of Nannopterum which, oddly has only two other species, the Neotropic and the Double-crested, both of which occur in North America. Perhaps an ancestor species to all three made it to the Galapagos Islands.

Flightless Cormorant, Fernadina Island, Galapagos Archipaelego

Even for a cormorant, it’s awkward on land and when it moves it looks like it is falling forward. It has a disproportionately large head that lends to that awkward appearance. But at least for WC, seeing it walk seemed to demonstrate how penguins evolved.

Flightless Cormorants construct a voluminous nest, a large pile of seaweed painfully collected, just above the high tide line. They seem to build a new nest for each breeding attempt, or a new partner. The clutch size is 1–4 eggs, but typically only two eggs hatch. Incubation takes 33–37 days. The chicks are born naked, but promptly grow blackish down. The chicks are fledged in about 60 days. The parents continue to care for and feed the fledged chicks for as long as 120 days, although in later stages the young are fed only by male, while female may initiate a second breeding attempt. In successful nests, three-quarters of the time just one chick fledges.

Sexual maturity can be reached in the second year, especially in females. This species’ longevity is probably in excess of 15 years.

Because of the small, slow reproduction and fluctuating population, and the extremely small range, Flightless Cormorants are classified as Vulnerable.

For more bird photographs, please visit Frozen Feather Images.

One thought on “Return of Bird of the Week: Flightless Cormorant

  1. There was also a flightless or semi flightless cormorant reported by Georg Stellar on Bering Island off Kamchatka, known as the spectacled cormorant. It apparently became extinct around 1850.

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