BIOLOGICAL SURVEY. 241 



BIRDS OF PORTO RICO. 



During the year a report on the birds of Porto Rico was issued. 

 The work upon which this is based was done at the request of and 

 in cooperation with the Porto Rican Department of Agriculture. 

 The treatise is the most comprehensive on the economic value of birds 

 ever issued for any locality in tropical America, and is one of the 

 most important local bird studies ever made. One hundred and 

 sixty-two species of birds are known to occur in Porto Rico, and the 

 report gives data on the food habits of about 100 of them. In most 

 cases the economic treatment is detailed, and it is shown that a num- 

 ber of the island birds are enemies of the most serious pests of Porto 

 Rican agriculture. Thus 21 species were found to feed upon the 

 changa, or mole cricket, 17 on the cane root-borer, 6 on the stalk- 

 borer, and 6 on the May beetle, all of which are pests of sugar cane. 



WILD-DUCK FOODS. 



The bureau has published three bulletins dealing with the value 

 and methods of propagation of more than 60 kinds of important 

 wild-duck foods. The information thus furnished has been widely 

 used and is in great demand. A revision of the first two publications 

 on the subject has been prepared, as they are out of print. Much 

 additional information has been included in the revision regarding 

 the plants originally treated, and 40 others are recommended with 

 the view of stimulating dealers to add them to their stocks. 



THE INTRODUCED STARLING. 



The European starling, long since introduced into the United 

 States, has only recently greatly extended its range. The species 

 is hardy and efficient and well equipped for the struggle for existence. 

 The increase of the bird and its spread into new districts have em- 

 phasized the need of an investigation of its economic standing. For 

 some time information has been sought by correspondence and by 

 laboratory examination of stomach contents, and at the present time 

 two assistants are studying the bird's habits in the field. A report 

 on the result of the investigations is planned for the coming fiscal 

 year. 



THE CROW. 



In an article on " Winter Crow Roosts," published in the Yearbook 

 for 1915, the roosting phase of crow life was fully described and the 

 economic significance of crow roosts discussed. An extensive report 

 on the relation of crows to man was completed. The essential conclu- 

 sions are that crows are about equally beneficial and injurious, and 

 that they are so wary and sagacious as not to need legal protection. 

 Lack of this, while not endangering the species, will permit farmers 

 to protect their crops or other property whenever necessary. 



BIRDS OF THE SOUTHEASTERN STATES. 



In response to an urgent need for information on the subject, a 

 Farmers' Bulletin on common birds of southeastern United States 

 has been prepared. It shows that every important insect pest of the 

 South has its bird enemies, large numbers of the corn-leaf beetle, the 



