Ruins in the centre of Christchurch have become home for hundreds of the world's most threatened gulls.
The black-billed gulls have set up a colony of nests in the demolished remains of an office block on Armagh Street.
Tarāpuka are only found in New Zealand, but usually near rivers, not on concrete piles.
DoC Christchurch community ranger Vanessa Mander tells us about this unusual breeding place.