Caspian Tern 

The Caspian Tern is the largest of all terns, more like a gull in size. The heavy silver-grey body has white underparts with dark tips to the under wing and a short white forked tail. The massive red bill is tipped black and yellow. The adult has a black cap when breeding, which becomes flecked with white in non-breeding plumage. A slight crest at the back of the head gives it a triangular look.  The call is a loud harsh ‘kaaa’. 

Caspian terns feed mainly on small surface-swimming fish such as yellow–eyed mullet, smelt, piper, small flounder and inland species such as whitebait, bullies, trout and small eels. All are caught by plunging into the water (often fully submerging) at a steep angle from a height of 8–10 metres above the surface. 

Breeding takes place between late September and early December, usually in large loose colonies in harbours or among sand dunes.  Some pairs nest in isolation on small island beaches, shingle riverbeds or on lake shores. The nest is a shallow, unlined scrape in the sand, in which the female lays 1-3 light stone-coloured eggs with dark brown spots. Both adults incubate for 26–28 days and brood the chicks for the first 5–10 days after hatching. The chicks fledge at 33–38 days and continue to be fed by their parents for several months. 

At least one pair of Caspian terns has been known to breed regularly in the vicinity of Tiritiri Matangi. They are often seen on or around the wharf.

Discover more about Caspian terns at New Zealand Birds On-line.

Photography by Max McRae © (adult on nest) and Kay Milton © (juvenile with parent on Tiritiri Matangi wharf)

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.