Letters

--I am engaged in investigating t h e ringing records of Blue Tits. Amongst the known causes of death it is astonishing to find that the mousetrap is a principal one. I t may be necessary to place r a t and mouse traps in gardens, b u t I suggest that they should be placed under a tunnel of stones or bricks. Tunnel traps are more effective for vermin and they protect such valuable garden birds as ...