The Australasian Gannet is a large seabird of about 89cm and weighing nearly 2.5 kg.  It is mainly white, with a buff yellow head, and black flight feathers.  The juvenile is  spotted above [grey/brown] with brownish streaks below.  The adult plumage takes 3-5 years to develop.

Gannets feed mainly on small fish and some squid taken from deep waters or harbours and estuaries.  They dive vertically from heights of up to 30m entering the water at tremendous speed.  They have inflatable air sacs beneath the skin on the lower neck and breast that act as shock absorbers as they enter the water.

Gannets range widely in NZ seas during winter but return to their breeding sites around June/July.  The nests are made within close proximity of other nests, out of seaweed and guano.  They usually lay just one egg, incubated for 44 days by both sexes.  The chicks fledge at between 13-17 weeks old where they will fly across the Tasman Sea to Australian waters. They remain there until 3-7 years old when they will return to their breeding site and will breed for the first time at about 5 years old.  There is a lot of chattering in the gannet colony but away from the breeding site the birds are normally silent.  Muriwai, in West Auckland, is the mainland colony closest to Tiritiri Matangi.

Gannets can often be seen from the wharf area, and island surrounds, diving for food in the waters close to the Tiritiri Matangi coastline.

Photography by: Peter Craw ©(left) and by Dr Kerry Rodgers © (right)

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