Could it also be a Collared Petrel Pterodroma brevipes dark morph? I'm going off of Brett/Ron/Mike's "Birds Seen That Day" list for the species. Collared and Herald's were the only ones they reported by March 29.
ED142155 AS30
near the Kap Ingrid fulmar colony. Possibly puked on by snow petrels which share the same colony
scores nesting under overhanging cliffs.