S1, E4: On the Pribilof Islands off the west coast of Alaska, Nigel sees puffins, cormorants, Arctic foxes and fur seals. Further north, the native Yupik people take him on a midnight boat ride around St Lawrence Island. Back on the mainland, Nigel finds herds of musk ox on the outskirts of Nome before flying to Barrow, the most northerly city in the USA.