On New Years Day, we flew to the Wright Valley. On our return, pilot Ryan showed us a seal track that you can see from just above Marble Point until nearly to the south east limit of the Wilson Piedmont Glacier, at the McDonald Hills. Over the summit you can see the track again, and you can follow follow it to the edge of the ice and beyond, heading SE in the direction of Explorers Cove.
This puts to rest, in my mind, any notion that all the seal carcasses on the glaciers were put there by the Navy pilots. Perhaps some of this went on, but seals are clearly moving themselves.