260 Trowbridge, Ha-ck Flights in Coiiuecticut. \''\'\-A- 



M-ater birds have been, for a long time, considered known. 

 Such is the case of the flights of the Golden Plover {Charadrius 

 dominicus) and the Eskimo Curlew {Nujnenius horealis)^ species 

 which are sometimes ver}- common, during their southward 

 journey, on the capes and islands of our eastern coast. The 

 blowing in shore of the birds, in their line of flight, by easterly 

 winds when, in August, they are migrating south far out at sea, 

 has been generally accepted as the cause of the sudden appear- 

 ance of numbers of these two species of the Limicola^, every 

 few years, flying over the island of Nantucket, Cape Cod, and 

 other such out-lying portions of our country as are washed by 

 the Atlantic Ocean. 



Land birds have also occasionally appeared in flights in great 

 numbers, and it has been my pleasure to have devoted some time 

 to observing the unusual gatherings and flights of the Falconida;. 



Some years ago, my attention was called to certain peculiar 

 actions manifested by the Hawks, during their migrations through 

 the New England States, and more particularly to great flights of 

 these birds, which often occurred in southern Connecticut in the 

 months of September and October, when most of these Raptores 

 pass that State on their way to the South in quest of warmth and 

 sunshine and a .hunting ground, where food is more easily pro- 

 cured, than in the bleak north, during the winter season. 



In the course of a number of years, while collecting ornitho- 

 logical specimens in the vicinity of New Haven, Connecticut, I 

 observed that on certain days early in the fall, almost annually, 

 immense flocks of hawks appeared migrating southward, and I 

 also noticed that several of the hawks, which were very abundant 

 during these flights, were of a species rarely found in Connecticut 

 at other times of the year. 



The hawks sometimes appeared in such great numbers, and so 

 suddenly and so irregularly, that I felt sure that there must have 

 been some underlying causes which influenced the fall migration 

 of these birds, and thus were gathered together into flocks a 

 family of birds, the species of which even, under usual conditions, 

 are seldom observed otherwise than alone or in pairs. 



I therefore determined to investigate the question and to 

 search for possible causes, which might have afi^ected the migra- 



