56 MICHIGAN SURVEY, 1905. 



THE ECOLOGICAL DISTRIBUTION OF THE BIRDS IN THE PORCU- 

 PINE MOUNTAINS, MICHIGAN. 



OTTO MCCREARY. 



The country in which these observations were made is largely included 

 w r ithin a narrow area about a mile wide which runs from Lake Superior 

 almost directly south, crossing Carp river about a quarter of a mile east 

 of Carp Lake. Few observations were made south of the Carp river valley. 



On account of differences observed in the environments of the bird life 

 of this region, it will be discussed according to the following habitats: 



I. THE LAKE SUPERIOR SLOPE OF THE FIRST MOUNTAIN RIDGE. 



1. Lake Superior ) Q , , T 



2. Lake Beach... [ Statlon L 



3. Cedar Swamp Station II. Sub. 1. 



4. Hemlock Forest Station II. Sub. 2. 



5. Hardwood Forest Station II. Sub. 2. 



6. Camp Clearing Station II. Sub. 3 and 4. 



7. Mountain Top and Escarpment Station III. Sub. 1-6. 



1. Lake Superior (Station /). 



This habitat includes the open water of the lake and is only a feeding 

 place for the birds, as it is impossible for them to nest here. 



The water is very cold, the temperature being about 58 F. during the latter 

 part of July. The shores are rocky and steep, the rocks in some places 

 making an angle of 30 with the surface of the water, and on this account, 

 aquatic life, with the possible exception of small algae and invertebrates, 

 was lacking along the edge of the water, so that waterfowls feeding on 

 these would be expected to occur here only occasionally, during the migra- 

 tion season. 



The only birds observed, were those of fish eating habits, such as mer- 

 gansers, loons and gulls. On July 21 a female American Merganser 'with 

 nine or ten young in the down was seen near the shore. On my approach 

 they swam out into the lake and were soon out of sight behind some rocks 

 that jutted into the water. Two adult Loons were seen the same day, and 

 two days later two Herring Gulls were observed flying over the lake. These 

 were the only birds seen in about fifteen trips made to the lake shore from 

 July 15 to August 13. 



2. Lake Beach (Station /). 



At this part of the lake shore, the beach is formed by the dipping of the 

 bed rock below the lake, thus making a barren rocky strip, almost destitute 

 of vegetation, between the waters edge and the trees. In addition to the 

 mosses and lichens that grew upon the rocks, the principal plants that 



