EATON BIRDS OF WESTERN NEW YORK. 5 



MIGRATION. 



The dates given for the appearance and disappearance of our 

 commoner species of birds are the averages taken from records 

 extending over periods of five years at Springville, six at Canan- 

 daigua, and four at Rochester. The dates of arrival and departure 

 have been found practically the same at these three stations, as 

 might be expected, when it is considered that Springville, though 

 nearer the winter home of our summer birds, is on a higher level, 

 and consequently is reached at a slightly later period than its latitude 

 alone would lead us to expect. 



Under normal circumstances, different species will be found to 

 follow the dates recorded. But it must be borne in mind that 

 exceptional weather conditions in March and April may hasten or 

 retard for many days the arrival of early migrants, while the time 

 of arrival of May migrants has been found to vary but few days at the 

 most. The autumn movements of birds are more difficult to observe, 

 but the figures given are the best that can be offered in the present 

 state of our knowledge. For a graphic representation of the migration 

 of all species which have been definitely recorded for this region, the 

 reader is referred to the chart accompanying this list. 



HABITAT. 



An attempt has been made in the list to indicate briefly the 

 chosen habitat of each species. This while easy in the case of a bird 

 like the marsh wren, is more difficult in the case of such birds as the 

 robin, which is almost equally at home in the door-yard, orchard, 

 field and forest. 



NESTING DATES. 



Just as in the case of the migration records, the breeding data are 

 the result of many years' observations. The dates given are not 

 absolute, but are subject to the same variation as those referring to 

 migration, and noted under that heading. The earliest date given 

 under each species, is that on which the nesting has begun on at least 

 two different seasons, and the second date is the latest upon which, 

 under ordinary conditions, freshly laid eggs may be found. 



ECONOMIC VALUE. 



Little has been said in this list regarding the food of the different 

 species, but in the case of birds which are decidedly injurious or 

 beneficial, mention has been made of such fact for the guidance of 



