Ellsworth Land is a portion of the Antarctic continent bounded on the west by Marie Byrd Land, on the north by the Bellingshausen Sea, on the northeast by the base of the Antarctic Peninsula, and on the east by the western margin of the Filchner–Ronne Ice Shelf.[citation needed] The area west of 90°W is unclaimed, the area between 84°W and 90°W is claimed by Chile only, and the remainder by Chile and the United Kingdom as a part of the British Antarctic Territory.[1] This land lies near the center of the area traversed by American explorer Lincoln Ellsworth on an airplane flight during November–December 1935.[1] Information regarding the biodiversity of Ellsworth Land is comparatively limited due to the fewer research surveys and visitations in the region.Colonies of Adélie penguins have been observed on multiple offshore islands in the adjacent Amundsen Sea.