the western end of the Gulf of Mexico. This circuitous route adds 

 more than 2,000 miles to the journey of the swallows that nest in Nova 

 Scotia. The question may be asked : "Why should the swallow select 

 a route so much longer and more roundabout than that taken by the 

 blackpolled warbler.?" The simple explanation is that the swallow is 

 a day migrant while the warbler travels at night. The migration of 

 the warbler is made up of a series of long, nocturnal flights, alternated 

 with days of rest and feeding in favorable localities. The swallow, on 

 the other hand, starts its migration several weeks earlier and catches 

 each day's ration of flying insects during a few hours of aerial evolu- 

 tions, which at the same time carry it slowly in the proper direction. 

 Flying along the insect-teeming shores of the Gulf of Mexico, the 2,000 

 extra miles that are added to the migration route are but a fraction 

 of the distance that these birds cover in pursuit of their daily food. 



Although most of our smaller birds make their longest flights at 

 night, close observation will show that travel is continued to some 

 extent by day. This is particularly true during the latter half of a mi- 

 gratory season when the birds show evidence of an overpowering desire 

 to hasten to their breeding grounds. At this time flocks of birds while 

 feeding maintain a movement in the general direction of the seasonal 

 journey. Sometimes they travel hurriedly, and while their flights 

 may be short, they must cover an appreciable distance in the course 

 of a day. 



How Birds Migrate 



Speed of flight and speed of migration 



There is a widespread misconception concerning the speed at which 

 birds normally fly, and even regarding the speed they can attain when 

 occasion demands, as when closely pursued by an enemy. It is not 

 unusual to hear accounts of birds flying "a mile a minute." While 

 undoubtedly some birds can and do attain a speed even greater than 

 this, such cases are exceptional, and it is safe to say that even when 

 pressed, few can develop an air speed of 60 miles an hour. They do, 

 however, have two speeds, one being the normal rate for everyday pur- 

 poses and also for migration, and an accelerated speed for escape or 

 pursuit; this in some cases may be nearly double the normal rate of 

 movement. Nevertheless, it is doubtful if the effort required for the 

 high speeds could be long sustained, and certainly not for the long- 

 distance migratory journeys that are regularly made by most birds. 



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