120 



THE OOLOGIST. 



are ravines out of which now cool springs 

 and pleasant waters. 



Beyond, the praires of what 



remains since thriving farms have been 

 established, but we go no farther. 



The reader will therefore see that the 

 valley is so adapted that quite a variety 

 of bird life may be found. 



It has been discovered b3^ investiga- 

 tion that the tide of migration follows 

 the water courses. The Illinois is so 

 situated that it forms an important 

 highway to transient species-. The vast 

 multitudes of transients moving upward 

 tlrrough the great Mississippi Valley in 

 the spring, do not all keep in the direct 

 course of this river. Many branch off 

 up the Missouri Valley, some up the 

 Ohio, the majority probably follow up 

 the Mississippi, but those bound for the 

 region of the Great Lakes, strike up the 

 Illinois, cross or follow up Lake Mich- 

 igan and thus reach their summer 

 home. 



Food and shelter are two essential 

 elements which tend to allure transient 

 species. With both of these the Illinois 

 is abundantly supplied. 

 [-The great numbers of water fowl pass- 

 ing semi-annually through the valley, 

 find an abundant supply' of both food 

 and shelter in the numerous ponds, 

 lakes and sloughs. 



The smaller species keep to the tim- 

 bered bottoms, the brush piles, the 

 weedy fields and roadside. Thus the 

 Valley is well adapted to both sustain 

 and shelter the thousands of transient 

 birds. 



The great variety of resident and 

 summer resident species to be found 

 in the valley, is due also to the food 

 and shelter afforded. 



The Illinois has fully her share of sum- 

 mer residents, The character of the 

 country is such as to insure good nest- 

 ing sites for many different species. 

 From the bottoms to the hills will be 

 found a rich field for an ormithologist's 

 research. 



While of course the number of re- 

 sidents do not begin to compare with 

 that of summer residents, it is by no 

 means small. 



The variety of winter residents de- 

 pends entirely on the severity of the 

 season. If mild, many of the transients 

 remain, while on the other hand, if the 

 weather proves severe, they remove 

 south and are replaced by more hardier 

 species from the north. The Snowy 

 Owl and Crossbills are an example of 

 such. 



The difference in latitude and long- 

 itude between the source and mouth of 

 the Illinois is enough to effect the fauna 

 of each extreme. For instance, the 

 Turkey Buzzard and Summer Tanager 

 are found in the Southern half of the 

 valley only, and the Boboblink and 

 Yellow-headed Blackbird belong to the 

 northern half. Some birds, summer 

 residents at the source, are residents or 

 winter residents at the mouth. I have 

 no doubt but what upon investigation 

 the western forms of certain species, 

 such as the Maryland Yellow-throat or 

 Meadow-lark, will be found to predomi- 

 nate at the mouth of this river, and the 

 eastern forms predominating at the 

 source. 



Many visitors appear on the river 

 which we otherwise would not have 

 were it not for Lake Michigan. These 

 species are gulls, terns and others of 

 like character, appearing as either sum- 

 mer or winter visitors. At Peoria, 

 where many of my observations have 

 been made, I have noticed that strong 

 northeast winds generally bring the 

 gulls. Undoubtedly they drift down 

 from the Lake with the wind. Other 

 marine visitors are not uncommon. 

 Western and southern visitors, or per- 

 haps I had better say stragglers, are 

 frequently taken. 



So far, I have endeavored to present 

 a descriptive article on the Illinois 

 Biver Valley as a collecting field for 

 an 01 nithologist. Veiy little, if any 



