30th Birthday Dinner

Date posted: 06-Sep-2018

Please join us in celebrating the 30th anniversary of the formation of the Suppo..

2019 Calendars now available

Date posted: 05-Sep-2018

The new 2019 calendars are now available and this year's is better than ever! Th..

Winners of kokako photo competition

Date posted: 02-Sep-2018

The stunning winning photographs from those submitted to the competition as part..

Kokako Celebration

Date posted: 21-Jul-2018

(https://www.eventbrite.com/e/the-great-kokako-story-celebrating-21-years-..

Kokako Photographic Competition

Date posted: 20-Jul-2018

KĊŒKAKO PHOTOGRAPHIC COMPETITION Celebrating 21 years on Tiritiri Matangi To ce..

New monitoring reports published

Date posted: 19-Jul-2018

Reports on monitoring studies carried out over the past year have now been poste..

2018 Concert coming up soon

Date posted: 15-Feb-2018

Our 2018 concert will feature an afternoon of light classics and jazz courtesy of the Auckland Ph..

Wetapunga talk coming soon

Date posted: 05-Feb-2018

For the Social on 19 March the speaker will be Ben Goodwin of Auckland Zoo, who will talk about t..

Rat caught and now takahe released from pens

Date posted: 28-Jan-2018

Thankfully DOC staff Andre de Graaf and Polly Hall and their assistants have trapped the rat whic..

Your Christmas Shopping for a Song

Date posted: 04-Dec-2017

Aka - The Grand Christmas Shopping Expedition to Tiritiri Matangi Island Shop Dreading..

Southern Black-Backed Gull

Scientific name:

Larus dominicanus dominicanus

Maori Name:

Karoro

 

 

Conservation status

Not threatened

Mainland status:

Widespread and locally common

Size:

60cm, 1050g (male); 850g (female)

Lifespan:

14 years average (oldest recorded - 20+yrs)

Breeding:

Mid October - Late January

Diet:

Opportunist, offal, carrion, refuse, marine invertebrates, shellfish, fish, eggs, frogs, lizards, birds, mammals, fruit.

Black backed gull, adult - photographer: Max McRaeThe black-backed gull is the largest gull in New Zealand. In the adult, the head, neck, underparts, rump and tail are white, the back and upper wings are black with a narrow white trailing edge. The bill is yellow with a red spot at the tip of the lower bill. The eye is pale yellow and the legs greenish yellow. First-year birds are brown and in the second year the back is brown and the breast and neck are white flecked with brown. By the third year the back and upper wings are brown and black. There is a large variety of calls but the most characteristic calls are a contagious 'uhuh, eeah–ha–ha–ha–ha–ha' or 'kaloo, kaloo, kloo, kloo, kloo, kloo' heard in breeding colonies or feeding flocks, and a non–contagious 'gorah, gorah' call mainly from breeding adults.

Black-backed gulls are opportunists, taking a wide variety of foods, including offal, refuse, carrion, marine invertebrates, shellfish, fish, eggs frogs, lizards, birds, mammals, small fruit and other plant material. 

Black backed gull, juvenile - photographer: Max McRaeBreeding takes place between mid October and late January, usually in large colonies near the sea shore. Some pairs nest alone or in small colonies on coastal rock stacks and headlands, mountainsides and roofs of city buildings. The nest built mainly by the male is a substantial mound composed of dry grass, seaweed, twigs and feathers, which has a small but deep depression in the centre. The clutch of 2–3 brownish or grey eggs with dark blotches is incubated by both parents for 23-30 days. The chicks fledge at 50 days and remain with their parents for at least a couple of months after fledging.


Several pairs of black-backed gulls breed on Tiritiri Matangi.

Find out more about black-backed gulls at New Zealand Birds Online.

Photography by: Max McRae © (adult on right, juvenile on left)

References: Heather, B.D.; Robertson, H.A. 2000 The Field Guide to the Birds of New Zealand. Auckland, Viking. Moon, G The Reed Field Guide to New Zealand Birds.