Black Tern

The Black Tern, scientific name Chlidonias niger, is a petite tern predominantly found near inland waters across Europe, Western Asia, and North America. Its plumage is primarily dark, and during the breeding season, it may exhibit a blue sheen, once earning it the name "blue darr." The genus name Chlidonias derives from the Ancient Greek for "swallow-like," a nod to its graceful flight, reminiscent of a swallow, which is also reflected in another of its old English names, "carr swallow." The species name niger means "shining black" in Latin.

Identification Tips

Adult Black Terns measure about 25 cm in length, with a wingspan of 61 cm, and weigh approximately 62 grams. They possess short, dark legs and a black bill that is nearly as long as the head, appearing slender and slightly decurved. The back is dark grey, with a white forewing, and the head, neck, and belly are black, sometimes with a grey suffusion in adults. The cap is black or blackish-brown, forming an almost complete hood with the ear coverts. The tail is light brownish-grey and 'square' in shape. Juveniles can be identified by a broadish white collar and a large dark triangular patch before the eye. In non-breeding plumage, the black is mostly replaced by grey, and the upperparts are drab with pale feather edgings.

Habitat

The Black Tern favors freshwater marshes for breeding, with a preference for nesting on floating material or very close to water.

Distribution

This species is widespread, with breeding grounds across most of Canada, the northern United States, Europe, and western Asia. In North America, they migrate to the coasts of northern South America, while Old World birds winter in Africa.

Behaviour

Black Terns are known for their dynamic and full wing-beats and often exhibit erratic flight as they dive towards the water's surface for food. They are similar in flight behavior to other tern species.

Song & Calls

The call of the Black Tern is a high-pitched "kik," and when in large flocks, their collective calls can be quite overwhelming.

Breeding

They lay 2-4 eggs per nesting attempt, either on floating material in a marsh or on the ground very close to water.

Similar Species

Hybridization with the White-winged Black Tern has been recorded, resulting in offspring that exhibit a mix of characteristics from both species.

Diet and Feeding

Their diet consists mainly of insects and fish, as well as amphibians. They forage on the wing, picking up items at or near the water's surface or catching insects in flight.

Conservation status

The Black Tern is currently listed as Least Concern by the IUCN. However, the North American population has seen a decline due to habitat loss. The species is protected under the Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA).