A black tern has been found along the Kapiti Coast and has been, for the last few days, the focus of any real birder in New Zealand. A first for NZ, making it a very special bird. I made a trip to Waikanae Estuary to see it, but dipped out, as it had disappeared. It resurfaced again a few days later at Plimmerton, and this time I got lucky. Its presence in NZ, along with a whiskered tern in Southland, several white-winged black terns, and the NZ black-fronted tern, means all four marsh terns (all of the same genus) are here, a first for the world. Its usual location is North America and Europe, so it is well out of its expected range.