The Heligoland Bird Observatory (Vogelwarte Helgoland in German), one of the world's first ornithological observatories, is operated by the Ornithologische Arbeitsgemeinschaft Helgoland e.V., a non-profit organization which was founded in 1891 to support research on the fauna of Heligoland, a small German archipelago, comprising the islands of Heligoland and Düne, in the Heligoland Bight of the North Sea. The principal research focus is on bird migration through banding studies. Over 400 species have been recorded. OAG Helgoland produces an annual bird report.