116 Adams, Ecological Succession of Birds. [a^'^i 



from ocean to beach birds, onw^ard to those characteristic of wander- 

 ing and fixed forested dunes. These relations are outhned simply 

 to indicate the problem and its causes, which need detailed investi- 

 gation. 



In Michigan a few habitat studies have been made. One in the 

 Porcupine Mountains, on the south shore of Lake Superior, and 

 another on Isle Royale. Both are by McCreary; the paper on the 

 latter area is unpublished. The summer birds of the Porcupine 

 Mountains are listed (McCreary '06) by selected localities and the 

 habitat preferences are discussed as follows: water birds, birds 

 frequenting the shores and banks of streams, birds frequenting 

 grassy meadows and alders, birds frequenting tamarack and cedar 

 swamps, birds frequenting hemlocks and maples, and birds frequent- 

 ing the cliff and mountain top. In its emphasis upon habitat pref- 

 erence this paper is the only one so far seen which at all approaches 

 Townsend's discussion of this subject. McCreary's work was done 

 without a knowledge of Townsend's. 



In southeastern Michigan, Brown ('06) made a locality study 

 and outlines the habitats as follows: birds found in orchards, 

 birds of the open woods, birds of the open fields, birds of the thicket, 

 and birds of the marshes and river. Brown's paper is intermediate 

 in character between the preceding papers and those of an eco- 

 nomic nature, to be mentioned later, because the area studied has 

 been so much influenced by man. 



There are a few papers which, although primarily faunistic or 

 geographic, contain habitat data. Such, for example, is Ridgway's 

 ('74) discussion of the birds of the AVabash Valley and ('89) the 

 birds of the Illinois prairie (pp. 13-16). An exceptionally good 

 paper of this character on the Louisiana birds is by Beyer, Allison 

 and Kopman ('06), although its aim and method of treatment differs 

 from that of Townsend. The bird life is, however, closely corre- 

 lated with the vegetation and the physical conditions of the State. 



The papers previously mentioned have been written from a 

 regional standpoint. The study however of all the various condi- 

 tions frequented by a given species or some natural group is also 

 an important and neglected method of ecological study which pos- 

 sesses certain important advantages. As an illustration of this 

 method may be mentioned Palmer's ('00) study of the INIaryland 



