a rare vagrant to kermadec waters

Size
Length: 18-20 cm, Weight: 35-45 g
Lifespan
10-15 years
Diet
Carnivorous. Feeds on small crustaceans, fish, and squid. Forages by pattering on the water's surface. Often follows ships and whales to scavenge scraps.
Habitat
Tropical and subtropical oceans. Breeds on remote islands in burrows dug into soft soil on steep, well-drained slopes.
Range
Tropical and subtropical Pacific and Atlantic Oceans. Breeds on islands in the Caribbean, South Atlantic, and Pacific. A rare vagrant to the Kermadec Islands of New Zealand.
Endemism
Visitor
Main Threats
Introduced predators on breeding islands including rats and cats that eat eggs and chicks. Light pollution disorienting fledglings near coastal towns. Climate change affecting prey distribution.
Population
Global population estimated at 500,000-1,000,000 birds. In New Zealand, a rare vagrant to the Kermadec Islands and occasionally the North Island coast.
Conservation Status
data_deficient
Human Risk
harmless
Handling Note
seabird, do not approach or disturb on nesting grounds
Conservation Note
Rare vagrant seabird; not assessed for conservation status in New Zealand.
Te Ao Māori
The white-bellied storm petrel has no recognised Māori name. It is a rare vagrant rather than a resident species. Storm petrels collectively were known to Māori as takahikare. This means "dancing feet". It is a reference to their pattering walk across the water's surface. These birds were seen as messengers of Tangaroa. He is the god of the sea. The connection is apt. The bird lives on the domain of Tangaroa. It dances on his surface. It is a visitor from the deep.
A small, dark storm petrel with a white belly. It flashes as the bird patters across the waves. It looks like a ghost on the water. This is a bird of the open ocean. It spends most of its life far from land. It rides the wind and feeds on the surface. Breeding takes it to remote islands in the tropical and subtropical Pacific. It returns to land only to lay its egg and raise its chick. Most people will never see one. The plumage is blackish-brown above. It is pure white below. A sharp dividing line separates the two colours. The tail is square. The legs dangle in flight. The feet paddle the air like a bird that forgot to retract the landing gear. These feet are sensitive to vibrations on the water's surface. This sensitivity helps it locate prey in the dark. It feeds on small crustaceans, fish, and squid. It patters across the surface with feet tapping the water. A storm petrel in feeding mode looks like it is walking on water. It does not dive. It cannot swim well. The flight is fluttery and bat-like. Rapid wingbeats mix with sudden banks. A white-bellied storm petrel in a stiff breeze is hard to follow. Breeding occurs on remote tropical islands. The nest is a burrow dug into soft soil on a steep slope. Or it might be a crevice among rocks. A single white egg is laid. Both parents share incubation duties. The chick is fed on regurgitated crustacean oil. It fledges at about two months. The call is a soft, purring moan. It is heard only at night on the breeding islands. In New Zealand, these birds are rare vagrants. They are occasionally seen in the Kermadec Islands. The species is closely related to the black-bellied storm petrel. The white-bellied variant has no stripe down the centre of its belly. The population is stable. It has a large range across the tropical Pacific. This is a creature of the wind and the waves. It belongs to the open ocean. It avoids the land except when duty calls. The white belly is a signal in the dark. It marks the species against its darker cousins. The numbers are steady. For now.