The grey-headed albatross is a bird of open water rather than sheltered coasts, so it tends to appear where the ship is furthest from land: crossing the Drake Passage or working through the swells of the Scotia Sea. It feeds at higher latitudes than the other mollymawks, which is exactly why sightings cluster in these stretches of open Southern Ocean rather than in more sheltered channels.
Its nesting grounds are the isolated islands scattered across the Southern Ocean, and South Georgia is where travellers on these routes have the best chance of seeing breeding colonies up close, alongside the wandering and black-browed albatrosses that share the same cliffs. The name is a simple, literal one: an ashy-grey wash across the head, throat and upper neck, visible even at a distance once you know to look for it against the darker mantle.
It is a circumpolar species, so the same bird you watch gliding beside the ship in the Drake could, in principle, be one that fledged on a remote island on the far side of the Southern Ocean. That scale is part of what makes an otherwise unremarkable grey-headed shape on the horizon worth a second look through the binoculars.