New reports on ruru nesting and Island conservation

Date posted: 02-Oct-2017

Two new reports have been added to the website. The first gives details of a summer students..

2018 calendars now available

Date posted: 27-Sep-2017

Our latest calendar, beautifully illustrated with images taken on the Island, is now available fo..

Guided walks for photographers

Date posted: 21-Jun-2017

For a wonderful day of wildlife photography please join us on Tiritiri Matangi Island for a Ph..

Ferry discounts for Supporters

Date posted: 18-May-2017

Tiritiri Matangi Island, the perfect winter's day trip. The birds are at their best, warm up w..

More kiwi for the Island

Date posted: 04-Apr-2017

In 1993 and 1995, sixteen little spotted kiwi were released on Tiritiri Matangi Island. The ma..

2017 Photo Competition

Date posted: 22-Mar-2017

It is that time of year again when we are looking for entries for our photo competition (and phot..

The 2017 concert

Date posted: 05-Feb-2017

This year's concert promises to be another wonderful and unique experience. Click here (/concert-..

Shorebird Film Festival at Devonport

Date posted: 26-Oct-2016

Click here (/miscellaneous documents/DevWaderFilms.jpg) for details of a forthcoming film festival c..

Extra Dawn Chorus Trip

Date posted: 20-Oct-2016

Stop Press: Extra Dawn Chorus trip now scheduled for Thursday 27th October 2016. ..

2016 AGM

Date posted: 06-Sep-2016

The 2016 AGM was held at the Kohia Centre at 7:30 pm on Monday 19th September. Click here (/..

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.