The hourglass dolphin is one of the more reliable sightings on a Southern Ocean crossing, precisely because it lives offshore rather than near land. It is commonly seen from ships crossing the Drake Passage, where its short, stocky body and sharply contrasting black-and-white markings make it easy to pick out even in a moderate swell. Sightings tend to come in brief, energetic bursts — a pod riding the bow wave for a few minutes before peeling off again.
Further south and east, travellers crossing the Scotia Sea or pushing toward the Antarctic Circle can encounter the same species, a reflection of its circumpolar distribution rather than any single migratory corridor. There is no fixed season attached to these waters in the record, so sightings are opportunistic rather than scheduled — worth keeping binoculars to hand on any open-water leg rather than waiting for a particular date.
One detail worth knowing before you go: the hourglass dolphin is the only cetacean species to have been formally accepted based solely on a witness account, described in 1824 from a drawing made in the South Pacific four years earlier. It is a reminder of how little was known about these waters, and how much of that knowledge still comes from people simply looking over the rail.