OF ILLINOIS BIRDS 



and now almost replaces Bewick's Wren; the Tufted 

 Titmouse, Carolina Wren, Prothonotary Warbler, 

 Long-billed Marsh Wren and Cardinal, which have 

 recently occupied, as breeding birds, portions of the 

 Transition Zone; and Bachman's Sparrow, originally 

 a Lower Austral species but now found breeding in the 

 Upper Austral if not in the Transition Zone. 

 It is also well known to observers that different species 

 of birds vary greatly in relative numbers in different 

 years, and also that while a few seem to be increasing 

 in numbers others are becoming more scarce, some to 

 the point of virtual extirpation, at least locally; while 

 several have completely disappeared in Illinois, as the 

 Passenger Pigeon the Carolina Paroquet and the Ivory- 

 billed Woodpecker, the first for some years actually 

 extinct, the other two very nearly so. As late as 1871 

 the Swallow-tailed Kite and Mississippi Kite were 

 abundant in Richland County, both breeding here. 

 Of the former I have neither seen a specimen nor heard 

 of anyone else seeing one during the past forty years, 

 and the last individuals (a pair) of the latter seen by 

 me were observed in July, 1910. Here in Richland 

 County the Wood Thrush and Carolina Wren are both 

 so rare now that not more than one or two, if that 

 many, are seen or heard each season. 



The Barn Swallow and Cliff Swallow have here both 

 entirely disappeared as breeding birds, in their case 

 the imported House Sparrow being directly responsible. 

 Matters of this kind are not only interesting in them- 

 selves but have a more or less important bearing on 

 the problems of geographic distribution, and local 

 observers have therefore the opportunity of adding 

 much valuable information on the subject. 



So much remains to be done in the way of working 

 out in detail the distribution of every species whose 

 breeding range includes only a portion of the state, 

 that until we have carefully prepared annotated lists 

 of the birds of practically every county we cannot hope 

 to indicate on a map with more than approximate ac- 

 curacy the limits of the several life-zones; the best 

 that we can do at present is to draw the boundaries 

 as they appear most probable in the light of our im- 

 perfect knowledge. 



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