RROCKEDDINGS 



OF THE 



WASHINGTON ACADEMY OF SCIENCES 



Vol. VI, pp. 429-437. [Plates xxv-xxxiv.] February 28, 1905. 



SOME INTERESTING BEAVER DAMS IN 

 COLORADO. 



By Edward R. Warren. 



Slate River, the stream on which were situated the beaver 

 dams and other structures which form the subject of this paper, 

 is in Gunnison county, Colorado. It is a clear mountain stream, 

 flowing in a southeasterly direction past the town of Crested Butte, 

 a place of about 1,000 inhabitants, and the location of a coal 

 mine and coke ovens employing some 300 men. The altitude 

 is 8,900 feet. It heads about 10 miles above Crested Butte, and 

 is fed by tributary streams. That portion immediately north of 

 the town flows with a very crooked winding course through an 

 almost level bottom, thickly overgrown with clumps of willow 

 bushes. 



For several years I had noticed with interest old and new dams 

 and one or two houses at various places along the river and in 

 some of its tributary sloughs, and in 1902 my attention was par- 

 ticularly called to some new work farther down the river than 

 any I had seen before. This work may have been begun in 

 1901, as, on account of other matters, I had paid little attention 

 to the beaver that season, but the freshness of much of the con- 

 struction showed that it had largely been done in 1902. 



After a preliminary examination it was evident that I had 

 found something quite different and much more extensive than 

 any beaver work I had seen before, and that it was so compli- 

 cated that the quickest way to unravel it would be to take transit 

 and stadia rod and survey it, which was done. Besides sur- 



Proc. Wash. Acad. Sci., February, 1905. ( 429 ) 



