Phaeton aethereus (above)
Fregata aquila (below)
aus: NAUMANN, NATURGESCHICHTE DER VÖGEL MITTELEUROPAS: Band XI, Tafel 3 - Gera, 1903 digitale Bearbeitung : Peter v. Sengbusch - b-online@botanik.uni-hamburg.de

Source: http://www.biologie.uni-hamburg.de/b-online/birds/1615_60.htm

Source: https://commons.wikimedia.org/wiki/File:Fregataaquila.jpg

The red-billed tropicbird (Phaethon aethereus), also known as the boatswain bird is a tropicbird, one of three closely related seabirds of tropical oceans. The scientific name is derived from Ancient Greek phaethon, "sun" and Latin aetherius, "heavenly". The red-billed tropicbird occurs in the tropical Atlantic, eastern Pacific and Indian Oceans.

The Ascension frigatebird (Fregata aquila) is a seabird of the frigatebird family Fregatidae which breeds on Boatswain Bird Island and Ascension Island in the tropical Atlantic Ocean. The Ascension frigatebird is a large lightly built seabird with brownish-black plumage and a deeply forked tail.