These are the large, unripe drupes of the New Zealand Karaka tree (Corynocarpus laevigatus). They are coloured orange when ripe. Several bird species feed on ripe Karaka fruits – among them the Silvereye, Myna, Starling, House Sparrow and the Blackbird. The only birds that swallow a whole fruit are the New Zealand Pigeons (Kereru), and they are well-known dispersers of the seeds. Blackbirds may also disperse the seeds by carrying the fruit further off from the tree.
But be warned, the fruit is extremely toxic to both humans and dogs, and must on no account be eaten. Maori state that the pulpy part of the fruit is edible, though bitter, but the seed highly poisonous unless carefully prepared by cooking and soaking. Early cases of poisoning by eating Karaka were not uncommon.