Robber screen in action

There is a very weak colony in this nuc that was being robbed out. Made this simple robber screen from number 8 mesh and it is working well. The robber bees are piled up at the bottom because that is where they smell the honey. The local bees know to go up the channel to exist and to go back in. The mesh is stapled only to the front of the hive so that I can remove it from the bottom board, if needed.