pigeons is for distances which can be covered in a few hours. As soon as we take 

 distances which cannot be covered in one day, the average rate of speed is very 

 low — about two and a half days being necessary to cover a distance of six hun- 

 dred and fifty miles. The rate of flight even for short distances depends upon a 

 number of things, such as the brightness of the day, favorableness of winds and 

 weather, and the health and hardiness of the bird. When the maximum distance 

 of one thousand miles is called for, the average rate of flight is extremely low : 

 from nine to fourteen days is a splendid record. It is not uncommon for the 

 birds to take fifteen, sixteen, and twenty days for such a journey. They some- 

 times return from such a distance after months or even years. Only a few of the 

 birds released one thousand miles from home ever get back, but the percentage of 

 "returns" cannot be definitely stated. Pigeon-fanciers are so much interested in 

 the few which do return that they rarely say much about the birds which fail. 



Few records exist which are at all trustworthy of the distance from which 

 birds can return over an ocean pathway. There is one authentic case on record 

 where one pigeon was carried from Havre (France) to the Scilly Isles and there 

 released. This bird found its way back. The distance is approximately two hun- 

 dred and fifty miles. 



How do we know that the pathway over which the bird returns is unknown ? 

 This is the crux of the whole matter. The homing pigeon is extremely keen- 

 sighted. The very methods by which we train him to "home" make it possible for 

 him to become familiar with an enormous territory. Simply because he cannot 

 see his cote or even the town in which the cote is situated is no proof that he is not 

 returning by the aid of visual landmarks. If the bird is five hundred miles from 

 his home, and there is a mountain range between him and his home, it would serve 

 the same purpose for him to perceive this mountain range and direct his flight 

 toward it as if he could directly perceive his nest and young. With the methods 

 of training homing pigeons which we have at present we can never be sure that 

 the territory through which the bird directs his flight is ever wholly unknown to 

 him. Furthermore, until we have more accurate records both of the number of 

 birds which return and of those which do not, we can never be sure that the excep- 

 tional bird which does get home has not accomplished it by accidentally flying into 

 a familiar territory. 



It was this thought which led me to make a study of distant orientation in 

 two species of tropical birds which are found upon Bird Key — a little deserted 

 mound of sand about three hundred yards in diameter lying in the middle of the 

 Gulf of Mexico. This key is a member of the Dry Tortugas group (sixty-five 

 miles due west from Key West). The birds in question are the noddy and sooty 

 terns, belonging to the gull family, and not differing much in general size from the 

 homing pigeon. In the fall and winter months they are to be found distributed 

 generally over the tropical waters of the Caribbean Sea. On the first day of May, 

 almost to the day, about twenty-five to thirty thousand of them migrate to Bird 

 Key, and remain there for the nesting season. Bird Key is thus the northern limit 



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