Pseudobulweria

Pseudobulweria is a genus of seabirds in the family Procellariidae. They have long been retained with the gadfly petrel genus Pterodroma despite morphological differences. mtDNA cytochrome b sequence analysis has confirmed the split out of Pterodroma and places the genus closer to shearwaters. They thus represent either a plesiomorphic lineage still sharing some traits of the ancestral Procellariidae with the gadfly petrels, or convergent evolution of a shearwater to the ecological niche of gadfly petrels.

Description and ecology
They are generally largish darkish petrels, but may have white undersides. Long-winged, they fly about with rather leisurely wingbeats and soar a lot. Though they are attracted by chum, Pseudobulweria petrels are not particularly prone to following ships. They often approach floating prey from downwind, picking it up without landing on the water or during a brief landing in which the wings are kept raised.

The breeding range of Pseudobulweria is limited essentially by the Equator and the Tropic of Capricorn, and possibly always has been. Non-breeding birds range more widely, but in general they are rarely met with in the Northern Hemisphere or outside tropical regions. Today, the genus inhabits only the Indo-Pacific region; formerly it was also found in the Atlantic. Three of the Pseudobulweria species are listed as Critically Endangered. The Fiji Petrel (P. macgillivrayi) and Beck's Petrel (P. becki) are among the least well known seabird species on Earth, with the breeding colonies of the Beck's Petrel being completely unknown. Both species have been seen very seldom since their discovery by science. Only the Tahiti Petrel (P. rostrata) is more common across the Pacific Ocean, but it is still listed as Near Threatened. One species of Pseudobulweria has gone extinct in recent history; it has been described from subfossil remains found on Saint Helena.

Species

 * Fiji Petrel, Pseudobulweria macgillivrayi
 * Tahiti Petrel, Pseudobulweria rostrata
 * Beck's Petrel, Pseudobulweria becki
 * Mascarene Petrel, Pseudobulweria aterrima
 * Large Saint Helena Petrel, Pseudobulweria rupinarum – extinct (early 16th century)