northern Colorado. Since these tanagers do not reach northern 

 Colorado until May 20, it is evident those present in Alberta on that 

 date, instead of traveling northward through the Rocky Mountains, 

 their summer home, actually reached there by a route that carried 

 them west of the Rockies to southern British Columbia and thence 

 eastward across the still snowy northern Rocky Mountains. 



Pacific Oceanic Route 



The Pacific oceanic route is used by the Pacific golden plover, 

 bristle-thighed curlew, ruddy turnstone, wandering tattler and 

 other shorebirds. The ruddy turnstone, and probably other 

 shorebirds, migrating from the islands of the Bering Sea, have an 

 elliptical route that takes them southward via the islands of the 

 central Pacific and northward along the Asiatic coast. In addition, 

 many seabirds that breed on far northern and southern coasts or 

 islands migrate up and down the Pacific well away from land except 

 when the breeding season approaches. 



The Pacific golden plover breeds chiefly in the Arctic coast region 

 of Siberia and in a more limited area on the Alaskan coast. Some of 

 the birds probably migrate south via the continent of Asia to winter 

 quarters in Japan, China, India, Australia, New Zealand, and 

 Oceania. Others evidently go south by way of the Pacific Ocean to the 

 Hawaiian Islands and other islands of the central and southern 

 Pacific. Migrating golden plovers have been observed at sea on a line 

 that apparently extends from Hawaii to the Aleutian Islands; it 

 appears certain some of the Alaskan birds make a nonstop flight 

 across the sea from Alaska to Hawaii. While it would seem incredible 

 that any birds could lay a course so accurately as to land on these 

 small isolated oceanic islands, 2,000 miles south of the Aleutians, 

 2,000 miles west of Baja California, and nearly 4,000 miles east of 

 Japan, the evidence admits only the conclusion that year after year 

 this transoceanic round-trip journey between Alaska and Hawaii is 

 made by considerable numbers of golden plovers. 



Arctic Routes 



Some Arctic nesting birds retreat only a short distance south in the 

 winter. These species include the red-legged kittiwake, Ross' gull, 

 emperor goose, and various eiders. The latter group of ducks winter 

 well south of their nesting areas but nevertheless remain farther 

 north than do the majority of other species of ducks. The routes 

 followed by these birds are chiefly parallel to the coast and may be 

 considered as being tributary either to the Atlantic or Pacific coast 

 routes. The heavy passage of gulls, ducks, black brants, and other 

 water birds at Point Barrow, Alaska, and other points on the Arctic 

 coast, has been noted by many observers. The best defined Arctic 

 route in North America is the one following the coast of Alaska. 



A migration route, therefore, may be anything from a narrow path 

 closely adhering to some definite geographical feature, such as a 

 river valley or a coastline, to a broad boulevard that leads in the 



