PELICAN ISLAND 205 



would indicate a higli mortality among the young 

 birds ; and, indeed, no less than !j-i dead young were 

 counted. Most of these, however, were birds which 

 were old enough to leave the nest, and death was 

 doubtless due to the thoughtlessness of tourist vis- 

 itors, who chase the young about until they fall 

 from exhaustion, or are driven too far to find their 

 way home. 



Estimating the number of young birds which 

 had left the 5!)4 deserted nests at 801 — which would 

 be an average of one and a half birds to the nest — 

 and adding two parent birds to each nest, we have 

 3,581 birds on wing and on foot. But this number is 

 to be increased by the 162 young that were still in 

 their nests, making the probable total population of 

 Pelican Island 3,7:;6. This calculation, however, 

 does not take into account the eggs, from which 

 almost hourly came new inhabitants of the island ; 

 and it is with these eggs, or rather with the nest in 

 which they are placed, that we may begin a brief 

 outline of the young Pelican's development. 



The Pelican, although a low type of bird, is 

 altricial, the young, unlike the offs])ring of Gulls, 

 Ducks, or Snipe, being hatched in a helpless condi- 

 tion. The nest, therefore, is not only an incubator 

 where with heat from the parent bird the eggs are 

 hatched, but it is a cradle for the 3'oung. Conse- 

 quently, Pelicans' nests are unusually complicated 

 structures as compared with the dwellings of other 

 birds equally low in the evolutionary scale. 



There was a very interesting and constant rela- 

 tion between the character of the nest and its site, 

 ground nests being composed largely or entirely of 



