You don’t have to worry about catching big beaver in Comstock Cages.  Pictured above is a 61 pound beaver taken in a 12x12x36, the largest beaver taken in the smaller Comstock Beaver Cage Trap to date.  Information and pictures acquired from others using traps with the same size opening, 12×12, indicate that this is not an unusual occurrence, but to be expected.  I have also seen a picture with a 58 and 64 pound beaver in cages of this size.  Though the traps are only 36 inches long, it took a 44 inch long beaver!  

This is another 66 pound beaver taken in a standard 12×18 Comstock Beaver Cage Trap.  One trapper in Massachusetts claims to have caught dozens of 60 pound beaver, some 70 pound beaver and even a couple of 80 pound beaver in untrapped areas in the Comstock Swim Through Beaver Cage Traps.