but also has both economic and esthetic vaUies. 

 Alaslva l^'nit personnel, studying beaver ecology 

 on tlie Kenai National ]\roose Range, have found 

 that ponds created by the animals provide suitable 

 habitat for vegetation highly attractive to moose 

 and waterfowl. Beaver ponds and dams can ben- 

 efit salmon by providing nursery areas for the 

 j'oung and by stabilizing water levels in streams. 

 Detrimental etfects of beaver dams include ob- 

 struction or delay to migrating salmon, wherein 

 the salmon may be subjected to inci-eased preda- 

 tion wlien concentrated below beaver dams. Also, 

 the adults may be forced to spawn in unsuitable 

 areas below dams, and mechanical injury niay be 

 inflicted on salmon attempting to pass over or 

 through the impounding structures. 



Management criteria of beaver on the Kenai 

 elalwrated as the result of tliis study are as fol- 

 lows: (1) Beaver dams blocking salmon runs can 

 safely be removed with dynamite after the down- 

 stream migrants have left the stream and before 

 return of the adults (May 1 to June 30). (2) 

 Before or after this period, the dams should be 

 pulled by hand in such a manner as to lower grad- 

 ually the head of water. (3) Drainages known 

 to contain important runs of salmon, primarily 

 red salmon, should be managed for this resouire, 

 and beavers should be removed when found in 

 conflict witli the salmon. (4) Beaver numbers 

 should be controlled by licensed trappers during 

 the regular season. (5) Beavei-s in areas where 

 they can be enjoyed by the public should be pro- 



Historioally important in America's development, the beaver occurs in every State or Province except Hawaii. No 

 wild animal has greater potential for modif.ving freshwater environments, and such changes, according to latitude, 

 topographic conditions, and the degree of modification, may be good or bad as they affect wildlife. Nearly all 

 of the Wildlife Research Units have studied beavers in cooperatiim with their host States, (Photo by Arnold O. 

 Haugen ) 



