HISTORY OF THE INVESTIGATION. 



The total extinction of the passenger pigeon and the near extinction 

 of several other birds is bringing to the American people convincing 

 evidence of the necessity of a thorough knowledge of the economic value 

 of birds. The large number of publications on the food habits of birds 

 issued by the U. S. Biological Survey and the State Agricultural Ex- 

 periment Stations also confirms the view that this work is of great 

 importance. California, with her well developed fruit and grain indus- 

 tries and her abundant supply of bird and animal life, must necessarily 

 become more and more interested in the conservation of those birds and 

 animals known to be beneficial, and in the extermination- of those known 

 to be harmful. 



It is a well known fact that certain birds continually give trouble 

 by destroying crops. Some of these same birds do an incalculable 

 amount of good by destroying certain pests such as mice and insects 

 which are injurious to vegetation. Still others because they have both 

 good and bad habits do not belong. to > either class. Opinion as to the 

 real value of certain birds varies greatly. This is often due to the fact 

 that but little is known of their real food habits. 



Continued complaints from the farmers and fruit growers of the 

 State have been made to the California Fish and Game Commission 

 regarding the losses to crops caused by the depredations of certain 

 birds. The Commission has been urged repeatedly to take strong meas- 

 ures to avert the damage done. The usual measure urged is that the 

 particular bird in question should be placed on the unprotected list. 

 On the other hand, many scientists and others interested in birds, have 

 pointed out the fact that birds not only confer a great benefit in keep- 

 ing down the number of injurious insects and weed seeds, but also that 

 they fill a niche in that balance of nature most suited to mankind which 

 cannot be and is not filled by any other form of life. Man profits 

 greatly by the services of birds, but not appreciating it, he returns evil 

 for good. Experience has shown that many of those complaining of 

 the depredations of birds have based their complaints on circumstantial 

 evidence, or on evidence not sufficiently reasoned out. Furthermore, 

 these complaints have brought out the fact that really very little is 

 known of the food habits of birds throughout the whole year. Certain 

 it is that a complete knowledge of the food habits of a bird is necessary 

 to a determination of its economic status. As a result, therefore, the 

 California Fish and Game Commission has felt that legislation should 

 be based on comprehensive scientific investigations as to the value of 

 birds, and not on circumstantial evidence. Consequently, an investiga- 

 tion into the relations of the birds of the State to agricultural and other 

 interests was instituted. 



In order that the investigation be both scientific and practical, it was 

 determined to obtain precise knowledge of the food of birds by field 

 2 31 KJ 



