Crossbows,[a good one],,,,they are plenty good enough to kill a little ole dog at 40 yards,,,pretty quiet,,,and if you can shoot a scoped rifle,,it don't take much practice,,,,the line between pet and varmit,,is a fine one,,,your pet,might be a varmit to me,and visa versa,,,if a strange dog is chasing or killing your animals,,,he has now become a varmit,,right up there with coyotas,coons,,foxes,BEAVERS,etc,,,no law against killing varmits that I know of,,if you can't shoot a gun cause you live in a town limit,,there are other options,,and crossbows would be a good choice....thingy