A dark, secretive petrel seldom comes to land. It prefers the vast emptiness of the tropical Pacific Ocean. The Tahiti petrel is a bird of mystery. It is poorly known and rarely seen. It breeds on a handful of remote volcanic islands in French Polynesia, Fiji, and the Solomon Islands. It spends the rest of its life at sea. The population is declining. No one is entirely sure why. The uncertainty is part of the problem. The plumage is dark brown above and below. A paler belly shows only in good light. The cap is darker than the back. This gives the head a hooded appearance. The bill is black. The eyes are dark. The bird is uniform. It is hard to see against the dark water. Predators cannot see it. This camouflage is effective. It serves its purpose well. It feeds on squid and small fish. It plucks them from the surface at night. During the day, it rests on the water or flies low. A Tahiti petrel feeding is a dark shape on dark water. The visibility is low. The detection is difficult. The flight is fast and direct. Rapid wingbeats drive it forward. A Tahiti petrel in a tropical storm is in its element. It rides the wind. The mechanics are sound. The energy cost is low. Breeding takes it to remote Pacific islands. These sites are far from human interference. The nest is a burrow dug into soft soil on a steep, forested slope. Or it might be a crevice among rocks. A single white egg is laid. Both parents share incubation. The chick is fed on regurgitated squid oil. It fledges in about three months. The cycle is slow. The risk is high. In New Zealand, Tahiti petrels are rare vagrants. They are occasionally seen in the Kermadec Islands. These are birds that have wandered from their breeding colonies in French Polynesia. The displacement is accidental. The survival is notable. The population is declining globally. Introduced predators are the main threat. Rats and cats eat the eggs and chicks. Pigs root through colonies. Climate change is also a threat. Rising sea levels threaten low-lying breeding islands. The pressure is multifaceted. The response is limited. The Tahiti petrel was once considered common. Now the birds are scattered. Their colonies are small. The numbers are not encouraging. The call is a low, moaning croak. It is heard only at night on the breeding islands. The sound carries in the dark. It marks the presence of the bird. In New Zealand, the Tahiti petrel is a prize for birders. It is a rare visitor. It is a bird that should not be here but sometimes is. The sighting is fleeting. The memory persists. It carries on.