2^ook Mt^^ anti fftebietus; 



Homing and Related Activities of 

 Birds. By J. B. Watson and K. S. 

 Lashley. Papers from the Department 

 of Marine Biology of the Carnegie 

 Institution. Vol. VII, 1915, pp. 1-104 

 (Publication No. 211 of the Carnegie 

 Institution of Washington). 



Dr. Watson's earlier studies * of the 

 Terns on Bird Key in the Dry Tortugas, 

 with particular reference to their homing 

 instincts, have already become part of the 

 literature of ornithology. In the present 

 publication he includes the results of 

 further studies and experiments made in 

 1910 and 191 2, and, with the assistance of 

 Dr. K. S. Lashley, in 1913. 



These later studies were centered 

 chiefly on the homing and related instincts 

 of the two Terns — Sooty and Noddy — 

 which breed by thousands in the Key, 

 where all the conditions are exceptionally 

 favorable for work on this vitally impor- 

 tant function in the life of migratory birds. 



An introductory Chapter giving a 

 resume of experiments on homing birds 

 and theories which have been advanced 

 to explain their homing powers, shows 

 how little of real value had been done in 

 this field, and how widely at variance are 

 the theories which have been offered in 

 explanation of observed phenomena — 

 chiefly in connection with homing Pigeons. 



There is also some most welcome, 

 because evidently authentic, 'Information 

 on Homing Pigeons Gathered from Prac- 

 tical Fliers,' in which it is shown that, in a 

 one-hundred-mile flight "with hardly any 

 wind," the birds fly at an average speed 

 of 1,400 yards a minute. With a strong, 

 favorable wind, they may reach a speed of 

 1,900 yards a minute but, with a head 

 wind, may be reduced to 600 yards per 

 minute. Flights are mentioned in which 

 Pigeons returned from a distance of 500 

 miles in ten and a half hours. Nearly ten 

 days, however, were required to return 

 from a distance of 1,000 miles. 



*The Behavior of Noddy and Sooty Terns. 

 Carn. Inst. Pub. 103; See also Bird-Lore, xi, 

 1909, p. 178. 



Important additions are made to the 

 studies of nesting habits already published 

 by Dr. Watson, and various experiments 

 having a direct bearing on the homing 

 problem were carried out. 



These were designed to determine the 

 part played by near, as compared with 

 distant orientation, to show the number of 

 days a bird which has been deprived of its 

 mate will remain at the nest, the length of 

 time which birds removed from the nest 

 retain the nesting habit, and the compara- 

 tive natatorial powers of the Noddy 

 and Sooty Terns, the two birds concerned 

 in these researches. 



The latter experiment showed that, 

 while both species are rarely seen resting 

 on the water, the Noddy can swim buoy- 

 antly for an extended period without its 

 powers of flight becoming impaired, but 

 the plumage of the Sooties when forced to 

 alight on the water, became so water- 

 logged in from two to four hours that they 

 could not fly. It hence seems evident 

 that, while migrating Noddies, might, if 

 need be, rest upon the water and later con- 

 tinue their journey, a Sooty must either 

 go to land or find some floating object, if 

 it desires to perch. A circumstance which 

 recalls our once seeing a Sooty riding on a 

 small bit of drift-wood far from land 

 between Progreso and Vera Cruz. 



The technique of the actual homing 

 experiments, in which marked birds were 

 sent from Bird Key in the Tortugas to 

 Key West, Mobile and Galveston is given 

 at length. It is now common knowledge 

 that, in earlier experiments of this nature, 

 Terns released off Cape Hatteras returned 

 to Bird Key. It has been suggested, in 

 explanation of this remarkable flight, that 

 the birds simply followed the coast-line 

 back to Key West, from which point it 

 was supposed they could see the Tortugas, 

 and although this theory will carry little 

 weight with those familiar with the factors 

 involved, its validity is completely dis- 



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