Ardenna bulleri
The Buller's Shearwater, *Ardenna bulleri*, is an elegant and distinctively marked seabird, a true pelagic wanderer of the Pacific Ocean. Medium-sized for a shearwater, it measures 40-47 cm in length with an impressive wingspan of 97-105 cm and weighs between 300-420 grams. Its upperparts are a striking dark brownish-grey, contrasting sharply with its pure white underparts and a prominent, dark 'M' pattern across its upperwings, a key field mark for identification. The undersides of its wings...
Exclusively pelagic, spending almost its entire life at sea over deep oceanic waters, coming to land only to breed in burrows on predator-free offshore islands.
Primarily consumes small fish (e.g., anchovies, sardines), squid, and crustaceans, foraging by surface-seizing, pursuit-diving, and shallow plunge-diving.
Buller's Shearwaters are highly social birds, often seen in large feeding flocks at sea, sometimes associating with dolphins and tuna. They are largely diurnal when foraging, exhibiting a characteristic 'shearing' flight low over the waves, punctuated by brief plunges or shallow dives to catch pr...
Buller's Shearwater has a highly localized breeding range, being endemic to the Poor Knights Islands (specifically Tawhiti Rahi and Aorangi) off the Northland coast of New Zealand. After breeding, which typically runs from September/October to April/May, these birds undertake a remarkable trans-e...
Near Threatened
- Buller's Shearwaters undertake one of the longest trans-equatorial migrations of any seabird, traveling from New Zealand to the North Pacific and back each year. - The distinctive 'M' pattern across their upperwings is a crucial identification feature, giving them the nickname 'M-Shearwater' am...