$(ctd): indicating that Lugensa does not belong there.It is certain that the allocation of the species to Pterodroma,as in HBW,1,p.241, is incorrect.
Mrine & highly pelagic;widespread but sparsely distributed at sea.Breeds on oceanic islands on ridges,slopes or flat ground,usually below 400m,but up to 1400m at Tristan da Cunha
"Breeds in winter,starting in April." (HBW,1,p.237)
Disperses widely in subtropical parts of Atlantic, Indian & west Pacific Oceans.,mainly 25°-50°S.Some birds near breeding islands all year round.Occasionally strays into subantarctic and Antarctic zones.