ISLE EOYALE AS A BIOT.IC EN\'IKONMENT. 



BY Dlt. CHARLES C. ADAJJS. 

 I. INTKOnrCTIOX. 



1. Itinerary and Personnel of the Paiii/. The University Museum 

 party left Ann Arbor, Michigan, June 21), and reached the abandoned 

 light-house at Rock Harbor, Isle Royale, on tlic morning' of July 5, 1905. 

 The party was composed of the fcdlowing: Is'. A. Wood, Dr. E. A. 

 Brown, Dr. H. A. Gleason, ^V. P. Holt, Otto Mcf'rcary, a camp hand, 

 B. F. Sa.very, and the writer. In general, the duties of the various 

 members were as follows : ^Ir. Wood, the ^Inseum taxidermist, 

 looked after the trapping of mammals and the preparation of bird and 

 mammal skins. He a\ as assisted by Dr. Brown, who gave most of his at- 

 tention to the stvidy of the, bird life, and ^^'ho remained with the party 

 until July 25. In the study bf bird life. Dr. Brown, Mr. Wood and Mr. 

 McCreary co-operated, the latter devoting his entire time to the ecolog- 

 ical phase of the work. Dr. Gleason devoted his attention to the collec- 

 tion and ecological study of invertebi-ates, particularly molluscs and in- 

 ' sects, and most of the photographs were taken by him. In collecting in- 

 sects about the camps, he was assisted by B. F. Savery. Jlr. Holt's time 

 was devoted to the study of the vegetation. The writer, who was in 

 charge of the expedition, gave special attention to the environmental 

 dynamics, biotic succession, and the general correlation of the work 

 of the various members of the party. 



During the stay at Rock Harbor, Pie;. J, the following localities were 

 examined : The shore, from the light-house south to the head of Conglom- 

 erate Bay; the region about the head of Rock Hai'bor and Sumner 

 lake; a. line from the mouth of Benson brook to Sargent Lake and Mc- 

 Oargoe Cove.; and the vicinity of Tobin Harbor; in other words, the 

 localities included in Stations I-IV. 



The party remained at Rock Harbor fi'om July ~) to August 1, and 

 then moved to Siskowit Bay. Here Mr. Max M. Peet joined the party 

 on August 8, and devoted his attention to collecting birds f nd mammals. 

 He also took a number of the photographs. While at the Siskowit 

 Camp, the bay and lake of that name were examined, and also the Hay- 

 town trail and the islands near the Isle Royale Light. All of these lo- 

 calities are included in Station V. 



On August 17 the party moved to Washington Harbor, and was then 

 partially disbanded. The members who remained made their headquar- 

 ters on the grounds of the Washing-ton Club, at the head of 'S'i'ashington 

 Harbor. After September .5 ^Ir. Peet alone remained there until the 

 22nd, in order that he might continue the study of the fall migration 



