aitzcuauhtli.

Ā-ITZ-CUĀUH-TLI, literally, “Golden Eagle of the water,” Osprey (Pandion haliaetus) [FC: 41] Aitzquauhtli: “It is like the Golden Eagle. Its head is a little golden, a little more black. Its bill is a little blackish, somewhat yellow. On its breast, its back, its wings it is completely black [and] gold…. It is named aitzquauhtli because when it goes flying high, if it wishes to eat, from there it streaks down. When it descends, it goes whirring, it suddenly dives into the water; it seizes whatever it wishes to eat, perhaps a fish. The lagoon water does not damage its eyes.” This could only be the Osprey.
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 11 – Earthly Things, no. 14, Part XII, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1963); and, with quotation selections, synthesis, and analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.

The Florentine Codex (Book 11, folio 45r) has a painting of this bird.
Available at Digital Florentine Codex/Códice Florentino Digital, edited by Kim N. Richter and Alicia Maria Houtrouw, "Book 11: Earthly Things", fol. 45r, Getty Research Institute, 2023. https://florentinecodex.getty.edu/en/book/11/folio/45r/images/a453ddd6-1... Accessed 17 October 2025.

an osprey
Henry M. Reeves, "Once Upon a Time in American Ornithology," The Wilson Journal of Ornithology 119:2 (June 2007), 317.