337d. Harlan's hawk. Buteo borealis harlani. Rare winter visitor; one specimen; natural habitat, Gulf States and lower Mississippi Valley.
339b. Red-bellied hawk. Buteo lineatus elegans. Rare migrant; Pacific coast species.
342. Swainson's hawk. Buteo swainsoni. Common resident; breeds everywhere below 11,000 feet.
347a. American rough-legged hawk. Archibuteo lagopus sancti-johannis. Somewhat common winter resident; arrives from the north in November and remains till March.
348. Ferruginous rough-leg. Archibuteo ferrugineus. Rather common resident; breeds on plains and in mountains; winters mostly on plains and along lower streams.
349. Golden eagle. Aquila chrysaetos. Resident; common in favorable localities; breeds from foothills to 12,500 feet; in winter on plains and also in mountains, often at 11,000 feet.
352. Bald eagle. Hallæetus leucocephalus. Fairly common resident; mostly in mountains in summer; on plains in winter.
355. Prairie falcon. Falco mexicanus. Not uncommon resident; breeds from plains to 10,000 feet; quite numerous in more open portions of western Colorado.
356. Duck hawk. Falco peregrinus anatum. Resident; not uncommon locally; breeds up to 10,000 feet.
357. Pigeon hawk. Falco columbarius. Summer resident; not common; usual breeding grounds 8,000 to 9,000 feet; some breed on the plains.