Beavers (Castor canadensis) were studied in the vicinity of Taiga Biological Station, 51-O2'40" W, 95-20'40" W on the Blind River and Wallace Lake, Manitoba. Data were gathered between September, 1986 and May, 1989. Beavers were live-trapped with Hancock traps from September, 1986 to October, 1984. Seventeen beaver were live-trapped a total of 24 times for an average of 24.9 trap nights per beaver. Trapping success was best in May and September - October. Cool temperatures may also be important in trapping success. Wind direction was significant in trapping success, but precipitation and lunar phase were not. Live-trapped beavers were outfitted wtth tall collar transmitters (3) or intraperitoneally implanted transmitters (7). A new surgical method of implantation using a ventral muscle-split technique is described.. Implanted transmitters had a longer lifespan than tall collars with no loss of range. Recapture of implanted animals showed continued growth of the beavers with no post-operative complications at 3, 11 and 16 months. The loss of one of the tail collars after one month had resulted in severe injury to the tail in a recaptured animal. Daily travel distances ranged from about 1 km to 8 or more km. Home range lengths varied fron O.55 km to 6 km. An adult male and subadult female had the largest daily movements and home ranges. No evidence was found of territoriality. Two dispersing beavers are known to have travelled 24 and 36 km, including at least 1 km of overland travel in the latter case. Winter under-ice movements were never more than 5O m from the lodge, and winter activity was sporadic. Above-ice activity was rare, and only occurred when night-time temperatures did not fall much below freezing.