THEIR ECONOMIC RELATIONS TO THE AGRICULTURIST 17 



THE HERRING GULL AND COMMON TERN. 



The gull family was mentioned in Circular 32 as a group bene- 

 ficial to farmers living in a prairie country. At the time, we re- 

 ferred particularly to the Black Tern so abundant in many of our 

 prairie sloughs, as a catcher of grasshoppers and, while no illus- 

 tration of this bird is available, we are pleased to be able to pre- 

 sent an excellent drawing of the Common Tern in this publica- 

 tion which will serve to illustrate the group. 



The Herring Gull — a good scavenger upon the shore of lake 

 or ocean, typifies the larger members of the family and the species 

 itself, while not as abundant perhaps as other gulls which breed in 

 some of our lakes — is, nevertheless, a Minnesota summer resi- 

 dent, arriving in the southern part of the state early in April, 

 shortly after that working its way north, where some at least 

 nest in our larger lakes, notably Lake Mille Lacs. I have ob- 

 served them at Devils Lake, Otter Tail County, in October and 

 also find the following observations amongst my notes taken some 

 years ago : "At Lake Mille Lacs, after the wind has been blow- 

 ing from the East a day or more, these gulls and the two follow- 

 ing species, namely L. delewarensis and L. Philadelphia, are plenty 

 along the west shore, flying up and down the beach and occa- 

 sionally alighting to pick up small lacustrine mollusks washed 

 ashore with the weed matter. About two miles from the south 

 shore of the lake lie three barren, rocky islands, which are fre- 

 quented by the gulls in the breeding season. The larger of the 

 three, called Stone Island, — or Spirit Lsland by the Indians — con- 



