1^8 Clark, Migrations of Shore Birds. [a"^ 



From this point their course is not accurately known ; but if we 

 apply this theory, they would follow down the northeastern tribu- 

 taries of the Amazons until they came within the influence of the 

 southeast trades, which would carry them southwest, over central 

 Amazonia toward Peru and Bolivia. 1 Somewhat northwest of the 

 Matto Grosso region, the birds would come under the influence of 

 the easterly winds on the southern border of the trades, which 

 would turn them south, and gradually (as they became more north- 

 easterly) southeast, which would bring the plover into the prairie 

 region of the Argentine. Here the prevailing westerlies of the 

 pampas region would be felt, and the birds would, under their 

 influence, continue down the eastern part of Patagonia toward 

 Tierra del Fuego. 



In returning, the birds would first go north (across the prevail- 

 ing westerlies), until in the vicinity of Buenos Ayres, and the 

 country just to the west of it where they would encounter north- 

 easterly winds, which would turn them inland, up the valley of the 

 La Plata and along the plains to the east of the Andes, the course 

 gradually becoming more northerly, and then northeasterly in the 

 area covered by the southeast trades. They would reach the 

 Amazons valley in its western half, and then under the guidance 

 of the northeast trades fly northwest, toward the isthmus of 

 Panama and Central America. The course from here would be 

 northwest across the trades to Texas and the Mississippi Valley. 

 The birds follow up this valley, northward, and then, on reaching 

 Canada fly northwest, across the prevailing southwesterly and 

 westerly winds to their breeding grounds in western Arctic 

 America. 



This, then, would be the path travelled by the main flights of 

 the Golden Plover. Those flocks which visit the lakes of Maine 

 and the eastern seacoast of the United States may very well be 

 parties which have become detached from the main body, perhaps 

 during a period of squally weather, with uncertain and variable 

 winds, conditions very liable to occur at the time of their journey 

 south. 



1 There are specimens in the British Museum from Peru taken in September 

 and October. 



