The birds sucked into the twin CFM56-5B/P turbofan engines of the US Airways Airbus A320 that ditched in the Hudson River on Jan. 15, 2009 were, in fact, Canada geese, says the National Transportation Safety Board. But researchers are still trying to determine if they were migratory geese from Canada, or local residents of the New York area.

The bird remains found in both engines of US Airways flight 1549 have been identified by the Smithsonian Institution's Feather Identification Laboratory as Canada Goose (Branta canadensis).

The lab made the identification for the NTSB through DNA analysis as well as through morphological comparisons in which feather fragments were compared with Canada Goose specimens in the museum's collections; the microscopic feather samples were compared with reference microslide collections.

Over two dozen samples of bird remains have been examined. Additional analysis will be conducted on samples received from the NTSB to attempt to determine if the Canada Geese were resident or migratory. While no determination has been made about how many birds the aircraft struck or how many were ingested into the engines, an adult Canada Goose typically ranges in size from 5.8 to 10.7 pounds, however larger individual resident birds can exceed published records.

The bird ingestion standard in effect when the CFFM56 turbofan was certified in 1996 included the requirement that the engine must withstand the ingestion of a four-pound bird without catching fire, without releasing hazardous fragments through the engine case, without generating loads high enough to potentially compromise aircraft structural components, or without losing the capability of being shut down. The certification standard does not require that the engine be able to continue to generate thrust after ingesting a bird four pounds or larger.