25 



very fast while swimming under water. It was diving to the 

 bottom and catching small fish there. This, he says, occurs 

 very often. 



UNDER-WATER MOVEMENTS OF CORMORANTS. 



The reader who has followed me thus far has noted much 

 conflicting evidence regarding the under-water habits of grebes 

 and loons. He will find similar contradictions in the statements 

 of authors and observers about the under-water progression of 

 cormorants. European authors do not agree about this. 

 Headley says, referring to diving: 



The Cormorant uses his feet alone to propel him, striking with both 

 simultaneously, and holding his wings motionless, though slightly lifted 

 from the body. The position of the wings must have given rise to the 

 idea, common among fishermen, that the Cormorant flies under water. 

 . . . But when you see him in a tank you can have no doubt that the 

 legs are the propellers. l 



This idea that a bird in a small tank will act exactly as it 

 would when free and in deep water has caused ornithologists 

 to draw false conclusions. The keen-eyed fishermen who had 

 watched the birds in their native haunts doubtless had much 

 better opportunities to study .their unhampered movements 

 than were afforded to Headley by specimens confined in the 

 limited area of a tank. One might as well study the habits of 

 an eagle in a flying cage. Both the cage and the tank offer 

 exceptional opportunities for observing captives, but such ob- 

 servations should never be regarded as conclusive in respect to 

 the behavior of the free wild creature. 



How the diving habits of water birds may be modified by 

 confinement in a tank is indicated by the following passage 

 from a letter from Dr. J. E. H. Kelso, Edgewood, British 

 Columbia: 



Some years ago, in the London Zoo, I came across an interesting case 

 of changed habits in birds. A keeper showed me a tank surrounded by 

 rock work, in which floated some guillemots. When feeding time came a 

 bucket or two of dead or moribund small fish were emptied into the 

 tank. The birds had ^0 exert ve/\ little effort to secure their feed, and 



i Headley, F. W.: Life and Evolution, 1907, pp. 125, 126. 



