Wyoming Birds. 15 



that swarm down from Canada in the fall and feed on the 

 rank growth of weeds bordering roadsides and cultivated 

 fields. He examined the stomachs of many Tree Sparrows 

 and found them entirely filled with weed seed, and con- 

 cluded that each bird consumed at least a quarter of an 

 ounce daily. Upon this basis, after making a fair allow- 

 ance of the number of birds to the square mile, he calcu- 

 lated that in the State of Iowa alone the Tree Sparrow an- 

 nually destroys about 1,750,000 pounds, or about 875 tons, 

 of weed seed during its winter sojourn." 



These quotations are, perhaps, sufficient to call attention 

 to the fact of the enormous economic value of birds. We 

 are likely to underestimate their services until we study 

 their habits more carefully than is our custom. Many birds 

 destroy a certain amount of grain and fruit, but even these 

 do more good than harm in nearly every case. With very 

 few exceptions, birds are beneficial and are protected by law. 



Aside from their practical value, birds add to our pleas- 

 ure. That being the case, it is well to attract them to our 

 homes by placing food where they are likely to seek it and 

 by planting shrubs and trees to which they may come and 

 build their nests. 



This bulletin is not intended to take the place of Prof. 

 W. C. Knight's bulletin on "The Birds of Wyoming," which 

 contains descriptions of the birds and many figures. It in 

 no way replaces the earlier work, but furnishes local lists 

 which should be of service to any who may wish to study 

 the birds of a certain locality. It brings together the work 

 of various collectors and observers who have given the sub- 

 ject considerable attention. It brings the result of the com- 

 bined efforts of all collectors up to date. As stated above, 

 forty-five new records for the state are established, as well 

 as a few new breeding records. Comments are added at the 



