ECOLOGY OF ISLE ROYALE. 87 



3. Tuinamck and Spruce Stvainps {Station II, 2 and 5). 



About a quarter of a mile north of Benson Brook there was a swamp 

 similar to I, 5, except that it was laroer and had more spruce and 

 tamarack trees scattered through it. The ground was covered with 

 sphagnum, Labrador tea, pitcher plants, etc., but apparently nothing 

 that would attract birds except the trees, 



The birds seen here were the Eed-breasted Nuthatch, Marsh Hawk, 

 Junco, Canada Jar, Black-throated Green Warbler, Black-throated Blue 

 Warbler, Chickadee, Golden-crowned Kinglet, White-winged Crossbill, 

 Yellow-bellied Flycatcher, and White-throated Sparrow. The Junco 

 probably strayed here from a large rocky clearing near by, as only 

 one was seen in the swamp, but it was heard in the clearing every 

 time I visited it. 



About a quarter of a mile further on toward Greenstone Ridge, the 

 trail crossed another swamp similar to this one, though it was somewhat 

 longer. Since the conditions were the same in these two places, many 

 of the same birds would be expected to occur in each, and this was the 

 case as will be seen by comparing the list given above with the following : 

 Olive-sided Flycatcher, Red-breasted Nuthatch, Nashville Warbler, 

 Canada Jay, Chickadee, White-winged Crossbill and Golden-crowned 

 Kinglet. 



Near Forbes Lake there were two other swamps and in these the fol- 

 lowing birds were seen: White-throated Sparrow, Canada Jay, Cedar 

 Waxwing, White-winged Crossbill, Red-breasted Nuthatch, Golden-crown- 

 ed Kinglet, Chickadee, Nashville Warbler and Flicker. All these were 

 found in both swamps with the exception of the Nashville Warbler and 

 Flicker. 



There is a marked similarity in the lists of birds seen in each of 

 these five swamps, and five of the species were found in all of them. 



Jf. Bock Ridge Clearings {Station II, 3). 



This habitat consists of all the rock ridges which were crossed by 

 the trail after it left Benson Brook. These ridges were nearly all bare 

 on the top, owing to the absence of soil. They had been burnt over 

 several years ago and the stumps that are left show that they were 

 originally almost if not entirely covered with forests. The trees that 

 were found in places where there was a little soil were almost entirely 

 aspen and birch. The birds found in this habitat were the Cedar Wax- 

 wing, Junco, Bay-breasted Warbler, Mourning Warbler, Robin, White- 

 throated Sparrow, Olive-backed Thrush, Sparrow Hawk and Red-eyed 

 Vireo. 



Very few birds were seen in the clearings, probably because the heat of 

 the sun drove them to the shade, as miost of the birds were observed at 

 the edge of the clearings, in places where the ground was partially 

 covered with trees. 



IV. WESTERN EXD OP EOCIC HARBOR AND TRAIL TO SUMNER LAKE. 



Thjs station comprised the western end of Rock Harbor and a por- 

 tion of the adjoining land. It was divided into five habitats. 



