126 Roosevelt Wild Life Bulletin 



convey some idea of the situation as actually encountered it will be 

 important to describe conditions in a number of localities in the 

 principal areas investigated. For this purpose I have selected all 

 the beaver flows in which the most extensive damage was found, 

 some examples to show where little or no damage has resulted or is 

 likely to occur, and others which represent fairly average conditions 

 or noteworthy features in other respects. 



i. Big Moose Lake Region. The most extensive flooding and 

 killing of timber in one continuous body is found along Constable 

 Creek (map i). From within approximately half a mile of the 

 mouth of this creek, which is in Big Moose Lake, and extending to 

 Constable Pond, there is a belt of drowned timber which, according 

 to my estimate, varies in width from about 10 rods at the lower end 

 to perhaps 18 or 20 rods as it approaches Constable Pond ; from 

 there a much narrower fringe extends along the north and south 

 shores of the pond. At the eastern end of the pond the two fringes 

 meet in a bay into which empties Pigeon Creek, and this bay contains 

 a close stand of dead timber, the bulk of it is spruce. The entire 

 distance of this flow is about two miles. On the creek I located five 

 dams in repair. The smallest of these was near Big Moose Lake 

 and was about 25 feet long and only 15 inches high, between the 

 water levels. It was in good repair when I saw it although it had 

 been repeatedly torn out previously, as it was on private land ; there- 

 fore no damage had resulted from this dam. The next dam, approxi- 

 mately half a mile up stream, was about 40 feet long and 1 foot 

 6 inches high and marked the beginning of the long flow (figure 1). 

 The uppermost dam was the largest, being about 300 feet long and 

 4 feet high between the upper and lower water levels. In the 

 stretch included between the second and the uppermost dam four 

 beaver lodges were found, two of them inhabited and possibly also 

 the third, while the fourth had been abandoned. Figures 2 to 5 

 inclusive show the conditions as they were found in this flow. It 

 will be noted that much of the timber is mixed spruce, birch and 

 balsam fir which at the time it was killed constituted a rather young 

 growth in a cut-over district, the trees being about 5 to 8 inches 

 in diameter and smaller. Constable Creek offers a good example of 

 the effects of beaver dams of very moderate size and relatively few in 

 number when placed across small streams normally only a few feet 

 wide but whose banks are low. 



As an example of a type of stream where little damage to timber 

 can result even from large dams, mav be mentioned the creek form- 



