CARNIVOROUS BIRDS 



49 



watching these little cormorants fishing. Their more ordinary 

 method is that of singly diving in the shallows, after the manner 

 of all their species. But instinct and an excessive abundance of 

 their natural food has taught these birds that by uniting their 

 forces a full stomach may be obtained with far less trouble than 

 the methods they usually employ. The plan resorted to is as 

 follows; and with the exception of one species of North African 

 pelican, it is one that is not followed by any other sea-bird that 

 I know of: The cormorants to the number of ten or twenty form 

 line, each bird being within a couple of feet from its neighbour, 

 and swim along the shore at right angles to the beach, the bird 

 nearest the land being only just able to float. In this manner 

 they advance, constantly inspecting the water beneath by im- 

 mersing their heads and necks until a shoal of small fish is 

 found. Then the whole line wheels, as it were, at once shore- 

 wards, most of the birds diving together in shallows, thus fright- 

 ening the fish, which escape before them in such quantities that 

 a large number are forced right out of the sea on to the beach 

 itself. These tactics are generally rewarded by a plentiful repast, 

 each bird resting on its breast amid the stones, and gobbling up 

 the fish as they spring 

 on all sides, attempt- 

 ing to regain their 

 natural element." 



The Darters, or 

 Snake- Birds (Plotus\ 

 of Africa, South Asia, 

 South America, and 

 Australia, may be de- 

 scribed as fresh-water 

 cormorants. They 

 are distinguished by 

 exceedingly sharp, 

 slender beaks, and 

 a narrow, swan -like 

 neck (fig. 339). These 



structural features are directly related to the habits. One of these 

 birds has been observed swimming under water in pursuit of a 

 fish, which was ultimately bayoneted by a thrust from the beak, 

 in making which the neck was suddenly straightened. The bird 



Fig. 339. A Darter (P lotus) 



VOL. II. 



36 



