New Zealand, on South I and at a few sites on North I (Rotorua, Gisborne, Clive, Porangahau). Winters mainly on southern North I and northern South I, some straggling to Stewart I and Snares Is.
Rarity Status
Currently this species is not classified as a rarity in this country OR information has not been updated.
Population
Estimated population is 96,000 (2010) and decreasing.
Status EN
Predation of eggs and chicks by Brown Rat (Rattus norvegicus) and freal cats, disturbance at nesting colonies by recreational use, spread of weeds reducing suitable nesting habitats are the main threats.
For more information see BirdLife International Species Factsheet.
Food
Terrestrial, freshwater and marine invertebrates, fish and shellfish.
Voice
A 'kek-kek' uttered in alarm. A 'kear' and 'kwow' uttered in aggression. A long 'kar'. A soft gurggling 'churr' in courtship.
Black-billed Gull (Chroicocephalus bulleri) [XC526368]
by Fernand DEROUSSEN from Kereta, Waikato, New Zealand (call)
Black-billed Gull (Chroicocephalus bulleri) [XC293082]
by James Lidster from Wanaka, Queenstown Lakes District, Otago, New Zealand (call)
Nest
In a shallow depression on the ground composed of rootlets and small sticks, neatly lined with grass.
Eggs (Guide)
2; pale grey, pale olive-green or pale blue, usually blotched with dark and light brown. Incubation: 20 - 24 days; by both parents.
Subspecies
No subspecies.
Similar Species
Silver Gull (Larus novaehollandiae) which has a shorter, deeper bill - red in adults, darker grey wings, more extensive black on wing-tips.
References
See References.
BirdLife International Species Factsheet