46 CIRCULAR 363, U. S. DEPARTMENT OF AGRICULTURE 
hand, the birds that have come south directly through the Mississippi 
Valley and the region west to the Rocky Mountains reach the coastal 
plains of Mississippi, Louisiana, and Texas and continue directly 
across the Gulf. The great majority of North American birds seeking 
winter homes in the Tropics thus elect the short cut across the Gulf 
of Mexico in preference to the longer although safer land or island 
journey by way of Texas or Florida. During the height of the mi- 
eration some of the islands off the coasts of Louisiana and Texas are 
wonderful observation places for the student of birds, as the feathered 
travelers literally swarm over them. 
One of the short cuts (fig. 20, route 5) that may be considered a part 
of this great water artery of migration extends a few hundred miles 
from the coast of Texas te the northern part of the State of Vera 
Cruz. As the neighboring coast is arid and thus entirely unsuited to 
the needs of birds that are frequenters of moist woodlands, it is not 
surprising to find that this Gulf route is used by such woodland species 
as the golden-winged warbler (Vermivora chrysoptera), the worm- 
eating warbler (Helmitheros vermivorus), and the Kentucky warbler 
(Oporornis formosus). 
Formerly it was thought that most of the North American birds 
that migrate to Central America made a leisurely trip along the 
Florida coast, crossed to Cuba, and thence made the short flight from 
the western tip of Cuba to Yucatan. A glance at the map would 
suggest this as a most natural route, but as a matter of fact it is prac- 
tically deserted except for a few swallows and shore birds, or an oc- 
casional land bird storm-driven from its accustomed course. 
Present knowledge of the chief tributaries to the Mackenzie Valley— 
Great Lakes—Mississippi Valley highway relates chiefly to waterfowl. 
Reference already has been made to the flight of the black ducks 
(p. 42) that reach the Mississippi Valley from southern Ontario. 
Some individuals of this species banded at Lake Scugog, Ontario, 
have been recaptured in succeeding seasons in Wisconsin and Mani- 
_ toba, but the majority have been retaken at points south of the junc- 
tion of the Ohio River with the Mississippi, definitely indicating their 
route of travel from southern Ontario. 
A second route that joins the main artery on its eastern side is the 
one used by the blue goose (fig. 10), the migration route of which is 
probably more nearly due north and south than that of any other 
North American bird. The breeding grounds, which only recently 
have been discovered, are in the Fox Basin region of Baffin Island 
and on Southampton Island. In fall these geese work southward, 
chiefly along the eastern shore of Hudson Bay, and upon reaching 
the southern extremity of James Bay they take off for what is prac- 
tically a nonstop flight to the great coastal marshes of Louisiana west 
of the delta of the Mississippi River (fig. 21). In some seasons the 
flocks make intermediate stops among the islands and sand bars of 
the Mississippi, as they are occasionally common in the general vi- 
cinity of Memphis, Tenn. Most of the birds push on, however, and 
during the period from the first of November to the last of March 
fully 90 percent of the species are concentrated in the area between 
the Sabine and the Mississippi Rivers. On the return trip northward 
there is sometimes a tendency for some of the blue geese to veer off 
toward the Northwest, as they are occasionally abundant in eastern 
South Dakota and southeastern Manitoba. It is of particular in- 
