Recent seabird identification guides (e.g., Tuck and Heinzel 1978; Harrison 1983, 1987) and articles on the Manx Shearwater (Puffinus puffinus) complex (e.g., Jehl 1982; Bourne et al. 1988) do not satisfactorily address the problem of separating the Manx Shearwater (P. puffinus) from Newell's (P. auricularis newelli) and Townsend's (P. a. auricularis) shearwaters—presumably because Townsend's and Newell's are Pacific Ocean species, while Manx is essentially a bird of the Atlantic Ocean.