UNITED STATES DEPARTMENT OF AGRICULTURE 



MISCELLANEOUS CIRCULAR NO. 69 



WASHINGTON, D. C. 



JUNE, 1926 



CONSTRUCTION AND OPERATION OF BIOLOGICAL 

 SURVEY BEAVER TRAP 



VERNON BAILEY, Biologist, Division of Biological Investigations 

 Bureau of Biological Survey 



ias "been r«v, 

 — see rev.ed. 

 "binders at 

 end of file. 



rpHE BEAVER TRAP devised by the Biological Survey and 

 ■*■ described in Department Bulletin No. 1078, " Beaver Habits, 

 Beaver Control, and Possibilities in Beaver Farming," has been 

 greatly improved and strengthened until entirely satisfactory in 

 operation. The new trap (fig. 1) has been thoroughly tested, and in, 

 March, 1926, a patent was obtained for the writer by the Department 

 of Agriculture and dedicated to the use of the people of the United 

 States. It is designed chiefly for capturing beavers alive for control 

 and propagation, and can be manufactured by anyone for personal use 



or for sale . The specifica- 

 tions and directions that 

 follow should enable any 

 machinist or practical me- 

 chanic to make the trap, 

 at a cost for materials, 

 in small lots, of about 

 and for shop work 

 about 



Fig. 1.— Biological Survey cage trap for taking beavers alive. A, Trap held partly open to show con- 

 struction. B, Trap set and ready to be placed in the water. The trigger stands erect in the center of 

 the set trap 10 to 12 inches high, so that when struck on any side by a swimming beaver it releases 

 trigger bars and springs, and then the trap jaws close and lock above the captive animal. Details of 

 construction shown in Figure 2 



MATERIALS REQUIRED 



(Italic figures in parentheses show the part as illustrated in Figure 2) 



1 cold-rolled steel bar 134 by 34 by 58 inches, for base bar (1). 



2 cold-rolled steel bars each % by -^ by 87 inches, for trap jaws (5). 

 1 piece of flat iron 134 by 34 by 54 inches, for cross bar (#). 



98480—26 



