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The day migrants include, in addition to some of the ducks and geese, the loons, cranes, gulls, pelicans, hawks, swallows, nighthawks, and swifts. Soaring birds, including broad-winged hawks, storks, and vultures, can only migrate during the day because their mode of flight makes them dependent on up-drafts created by heat from the sun for their long distance travels. On the other hand, swifts and swallows feed entirely on diurnal flying insects. The circling flocks are frequently seen in late summer feeding as they travel while working gradually southward. Formerly, great flocks of red-tailed, Swainson's, and rough-legged hawks could be seen wheeling majestically across the sky in the Plains States. In the East, good flights of broad-winged, Cooper's, and sharp-shinned hawks are still often seen, particularly along the Appalachian ridges.

Because many species of wading and swimming birds are able to feed at all hours, they migrate either by day or night and are not accustomed to seek safety in concealment. Some diving birds, including ducks that submerge when in danger, often travel over water by day and over land at night. Strong fliers like the snow geese can make the entire trip from their staging area in James Bay, Canada, to the wintering grounds on the Louisiana Gulf coast in one continuous flight. These birds are seldom shot by hunters en route between these two points but are often observed, when migrating, by aircraft pilots. Graham Cooch of the Canadian Wildlife Service tracked a flight of the blue phase of this species in 1955. The birds left James Bay on October 17 and arrived on the Gulf coast 60 hours later after an apparent continuous flight over the 1,700-mile route at an average speed of 28 miles per hour. Golden plovers, likewise, probably make the southward flight from the Arctic to the South American coast in one giant leap. Other Arctic species on their northward flight in the spring might prefer to fly at night in lower altitudes, but must necessarily fly during the day at higher altitudes because of the length of the days. Many warblers that normally fly at night may find themselves over water at daybreak and be forced to keep flying during the day until landfall is made.