Fr: Guifette des galets, Sterne des galets
Ang: Black-fronted Tern
Maori: Tarapiroe
All: Graubauch-Seeschwalbe
Esp: Charrán Fumarel
Ita: Sterna frontenera
Nd: Nieuw-Zeelandse Stern
Sd: Nya Zeelandskäggtärna
Photographer:
Ian McHenry
My New Zealand Birds
Text by Nicole Bouglouan
Sources:
HANDBOOK OF THE BIRDS OF THE WORLD Vol 3 by Josep del Hoyo-Andrew Elliott-Jordi Sargatal - Lynx Edicions - ISBN : 8487334202
KNOW YOUR NEW ZEALAND BIRDS by Lynnette Moon - New Holland Publishers – ISBN: 1869660897
BirdLife International (BirdLife International)
New Zealand bird status between 2008 and 2012
New Zealand birds and birding (Narena Olliver)
Wikipedia, the free encyclopaedia
Te Ara – The Encyclopedia of New Zealand
Black-fronted Tern
Chlidonias albostriatus
Charadriiformes Order – Laridae Family
INTRODUCTION:
The Black-fronted Tern is now included in the genus « Chlidonias » which gathers the “marsh terns”. They mostly live near inland waters rather than coastal or at sea. These terns have a short, slightly forked tail, and their breeding plumage is usually darker, often dark grey, than in other species.
This species is endemic to New Zealand, and its Maori name is “Tarapiroe”.
DESCRIPTION OF THE BIRD:
Biometrics:
Length: 29-30 cm
Weight: 88-95 g
The adult in breeding plumage has black head from forehead to nape, and a narrow white cheek stripe. The body plumage is pale blue-grey on the upperparts. The underparts are pale grey. Rump, uppertail and undertail-coverts are white, but the tail is pale grey with darker tip, and is slightly forked. On the upperwing, the primaries are darker grey, and the outer primary has dark leading edge and white shaft.
The short, yellow-orange bill is sharply down-curved at tip. The eyes are black. Legs and webbed feet are yellow-orange.
The adults moult from mid-December to May.
The adult in non-breeding plumage has grey head and mottled-white crown. The nape is black, extending from eye to eye.
Both sexes are similar.
The juvenile has streaked or mottled black crown and nape. The back feathers show buff edges forming scaled effect. Breast and belly are grey, the throat is white, like the undertail-coverts. The bill is dark brown with dull orange base. Legs and feet are orange.
The immature resembles non-breeding adult. It has grey body plumage with brownish wings and tail. On the head, the crown is grey with black mottling. Ear-coverts and nape are black. The bill is dark brown with reddish-orange base. Legs and feet are orange.
RANGE:
The Black-fronted Tern occurs in interior South Island in New Zealand. This species was formerly breeding in North Island where it is today only a post-breeding visitor.
It breeds in eastern and southern regions of South Island, from Marlborough to Southland.
HABITAT:
The Black-fronted Tern breeds on riverbeds and migrate after nesting to coastal estuaries, fields, lagoons and harbours (where they roost).
It forages in coastal waters, up to 50 metres from the shore, but also on near-coastal farmland.
CALLS AND SONGS: SOUNDS BY XENO-CANTO
The Black-fronted Tern’s usual call is a repetitive « ki-ki-ki-kew » uttered in flight. This call is also used while feeding if others are foraging nearby.
They are usually silent away from the colonies and at roost, but the colonies are noisy when disputes occur between several birds.
BEHAVIOUR IN THE WILD:
The Black-fronted Tern finds most of its food along braided riverbeds where the nesting colonies are established. But it also forages in freshly ploughed areas where it can find grubs, insects, beetles, worms, and occasionally small lizards.
During winter and after the dispersion to estuaries and other coastal areas, it feeds mainly on zooplankton, small fish and crustaceans.
The Black-fronted Tern feeds in flocks during the breeding season, but mainly over land. They are very active over the rivers, touching the surface with the bill to catch nymphs of mayflies and stoneflies. They also fly above the streams to snatch insects in the air. They perform plunge-diving for fish.
The Black-fronted Tern is territorial at colonies and attacks intruders by diving and striking their heads with the feet, while calling loudly.
The displays include elegant aerial courtship displays such as “high-flight” and “fish-flight”. After courtship feeding by male to female, both sexes take off and fly high in the air, alternating with glides on rigid wings.
They usually nest in small colonies of 2-50 pairs, sometimes up to 250 pairs.
The Black-fronted Tern disperses after the breeding season to estuaries, lagoons, fields and harbours.
This species has distinctive buoyant flight when hawking insects over the fields. It is very agile in flight when foraging and feeding, with butterfly-like flight, dipping and raising, and flickering across the water while searching for food.
REPRODUCTION OF THIS SPECIES:
The laying occurs between October and December, and may extend sometimes into January.
The Black-fronted Tern nests in colonies with nests about 5-20 metres apart. This is a shallow scrape in the shingle, usually lined with twigs. It is placed near boulders and river stones, or at bush base.
The female lays 2 dark olive eggs with black spots. The incubation is shared by both adults during 21-25 days. The chicks leave the nest soon after hatching, about 1-3 days, and move away from the colony. They can fly at one month. They are fed by both parents and still depend on adults for food for at least two weeks after fledging.
They are strongly defended by adults against intruders.
PROTECTION / THREATS / STATUS:
The Black-fronted Tern is threatened by several factors, and between them, by habitat loss and recreational use of rivers. But the main threat comes from the introduced predators such as cats, rats, stoats and also harriers. In addition, their nests are vulnerable to flooding.
Conservation attempts with pest control and weed management have had limited success.
The population is placed in the band for 2,500/9,999 mature individuals, and has shown recent, rapid decrease of the numbers.
The Black-fronted Tern is currently considered as Endangered.
