The fairy prion is the smallest of its kind, and the most delicate in appearance. It is grey above and white below, with a dark M across the upperwings and a black tail tip. It looks like a tiny albatross, a bird that has been shrunk in the wash and come out the other side still perfectly proportioned. But the name is misleading. This bird lives through storms that sink ships. It dives through waves that would crush a human. It is not delicate. It is resilient. The bill is the giveaway. It is broad and flattened, fringed with fine lamellae that strain krill from seawater. A fairy prion feeding is a bird working a specialised tool. It flies low, head submerged, paddling forward. Water flows through the bill. Krill stays behind. Swallow. Repeat. The diet consists almost exclusively of crustaceans. Krill. Copepods. Small things that live in immense numbers. The prion has evolved to catch them efficiently. It does not chase. It filters. Flight is rapid and erratic, with twinkling wingbeats and sudden banks. In a storm, the fairy prion is in its element. It rides the wind, tilting from one gust to the next. On a calm day, it sits on the water, resting, waiting for the wind to return. It prefers chaos to stillness. Breeding colonies are enormous. Millions of birds gather on some islands. The noise at night is a constant chattering, purring, and whistling sound that rolls across the slopes. Each bird has its own burrow, a simple tunnel dug into deep soil. A single white egg is laid. Both parents share incubation duties. The chick hatches covered in grey down. It grows slowly, fed on regurgitated krill oil. That oil is energy dense. A single feed can sustain the chick for days. That matters when the parents are at sea for a week. In New Zealand, fairy prions breed around the South Island coast and on many offshore islands. The subantarctic populations are enormous. The birds are common. They are also almost invisible to most people. A small, grey bird that stays at sea. It is the most common prion in New Zealand waters. It is also the least known. A bird cannot be famous if no one sees it. Introduced predators such as rats and mice threaten breeding islands. Light pollution disorients fledglings near coastal towns, leading them astray. Climate change affects krill availability, disrupting the food chain at its base. The global population is estimated at several million birds. New Zealand hosts large breeding populations on subantarctic islands and around the South Island coast. The numbers are high. The visibility is low. The bird carries on.