The White-winged Tern is a vagrant from Europe or Africa.

A bird is considered a vagrant if it strays far outside its expected breeding, wintering, or migrating range.  The White-winged Tern, Chlidonias leucopterus, is a species of small tern in the family Laridae; the genus name is from the ancient Greek word “khelidonios,” which means swallow-like, or from the word “khelidon” for swallow. The White-winged Tern is generally found near bodies of fresh water in Europe, but, in winter, they migrate to Africa, southern Asia, and Australia. It is a scarce vagrant in North America, mainly sighted on the Atlantic coast, but there are a few records from the Pacific coast and inland in the Great Lakes area.

So what is it doing in the Caribbean?  That is an excellent question!

Although this sighting on Bonaire is not the first vagrant sighting of the White-winged Tern in the Caribbean, it IS the first sighting for the ABC islands–Aruba, Bonaire, or Curacao–so it’s a very exciting find!  White-winged terns have also been reported in Puerto Rico, Guadeloupe, Barbados, and the U.S. Virgin Islands, as well as southern Brazil, Paraguay, and Argentina in South America.

We shall never know exactly how these Eurasian or African birds arrive in the New World, but one theory is that perhaps they were blown west in a storm.  It’s a known phenomenon that birds, especially seabirds or migrating birds, can get into the trailing ends of a hurricane’s spiral, and they will tend to move toward the eye of the storm, where winds are calmer.  It’s easier to stay in the eye than to fight the high winds surrounding it, so as the storm moves west, so do the birds within its eye. Once the storm reaches land, it can begin to lose strength and the birds are able to get out of the storm.  However, they find themselves in a new location!

How to identify the White-winged Tern.

The White-winged tern observed here on Bonaire is in breeding plumage, so it displays short red legs and a short black bill, a black neck and belly, a very dark grey back, with a white rump and tail.  The wings, as the name implies, are mainly white. The inner wing is grayish with brown-tipped coverts.

Like other marsh terns, the White-winged Tern does not dive for fish, but rather skims and dips up and down along the surface of the water.  It will dip its head beneath the surface to catch small fish, but it will also feast upon insects while in flight.

It utilizes a shallow and leisurely wingbeat, which makes for a striking view when the bird is in breeding plumage, as one sees the alternating white and black with each wingbeat. They exhibit great aerial agility, which is probably the reason for the name-sake “swallow.”