On the move

After our second landing the ship is on the move again, heading for North Seymour Island.  While under way a group of  Frigatebirds started following us.  The males are the darker with the red pouch. Females have the white neck and chest.  There are Magnificent and Great Frigatebirds. I believe these  are Magnificent's.
They have a wingspan of 7.5 feet and can soar in the air for over a week, riding thermals and napping as it glides along.