This report is a comprehensive analysis of existing observational data (1943–99) and site evaluation data (1977–99) for locations used by whooping cranes (Grus americana) during migration through the United States portion of the Wood Buffalo–Aransas flyway.

The apparent migration path, as outlined by the distribution of whooping crane observations, is very similar to that delineated in earlier reports, following a relatively straight line north-northwest from Aransas National Wildlife Refuge (NWR) to central North Dakota then curving northwest along the Missouri Coteau to the North Dakota–Saskatchewan border. The distribution of spring and fall observations were relatively similar, except for the higher frequency of fall observations on Quivira NWR and Cheyenne Bottoms State Wildlife Area in Kansas, Salt Plains NWR in Oklahoma, and in Texas. Timing of spring and fall migrations also appears similar to that described earlier and shows no changes over the 57-year period of data collection. Regardless of season, most sightings included 1–3 whooping cranes, but groups with as many as 14 and 19 cranes have been sighted in spring and fall, respectively.