ID-t BIRD STUDIES WITH A ("AMERA 



questions of food and climate innst be considered, 

 we have here the problem reduced t(j its simplest 

 terms ; and in the desire for seclusion during the 

 breeding season which induces birds to conceal their 

 nests, if possible perhaps near Ijy, but if necessary 

 after a journc}' (jf varying length undertaken espe- 

 cially fijr the purpose, we have a good and sufficient 

 cause for the oi-igin of bird migration. 



An attemi)t t(j explain the present manifestation 

 of the migi'atory movement involves a study of tlie 

 climatic changes to which our globe has been sub- 

 jected. No doubt many birds controlled by "he- 

 redity of habit" make semiannual journeys which 

 at one time were necessary, but under existing cir- 

 cumstances are no longer required. Why, for ex- 

 ample, should the Boljolink winter south of the 

 Amazon, while its ally, the Red-winged Blackbird 

 {Agelaiu.s j>Ji(riiiri iis), does not leave the eastern 

 United States ? I Inive, however, no intention of 

 writing an essay on bird migration, and these 

 thoughts fii'e ])resented merely as pi'olimiuary to a 

 study of the life of Pelican Ishuid, of a visit to 

 which they arc^ in part the outcome. 



Pelican Island is situated midway between the 

 northern and southern extremities of Indian River, 

 near the eastern shore of a, key which here makes 

 the river abnnt three miles wide. It is triangular 

 ill shape and contains about three acres of ground, 

 on which grow a few black mangi'oves, a cabbage 

 l)alm or two, a,nd great- patches of grass; but at 

 least on(^ fonrtli of its surface is l.)aTe ground. 



On oni; of the islands of Uie near-by Narrows a 

 few pairs of Pi'own Pelicans are said to have nested. 



