Air speed of Red-necked Grebes (Podiceps grisegena), migrating in “no wind” conditions along a 2.64-km path along Lake Superior, Michigan in fall averaged 61.5 km/hr. Speed increased significantly using tail winds adjusted for wind vectors as the migration season advanced: 68 km/hr in August, 70.1 km/hr in September, and 78.7 km/hr in October. Horned Grebes (P. auritus) averaged 55.5 km/hr with no winds and, with tail winds, increased from 63.5 km/hr in September to 71.5 km/hr in October. Whether the increases indicate that late fall migrants are time constrained to complete their movement to wintering areas rapidly, or are a consequence of having to fly faster because of larger body mass at that season, remain to be fully explored. We also present flight speeds of 10 additional species of waterbirds migrating along the same path.