Flight 1475 from Dallas/Fort Worth to Denver landed safely just after 9 a.m. Tuesday after the bird strike, ABC News reported.
Officials said the Boeing 737's pilot was aware of the bird strike and declared an emergency. None of the flight's 151 passengers were injured, said Christen David, a spokeswoman for United Airlines.
The bird's remains were recovered from inside the aircraft and will be examined by experts at the Smithsonian Institution in Washington, who will help identify the species.
Paul Eschenfelder, an adjunct professor at Embry Riddle Aeronautical University, said jetliner engines are designed to be able to ingest a four-pound bird without putting passengers in danger. No plane engines are designed to survive an ingestion of an eight-to-15-pound bird, Eschenfelder said.