just looked out my OLD HANDS book, "THE AILMENTS AND DISEASES OF RACING PIGEONS" quote, sitting birds are constantly driven off their nests etc, perched birds can be seen to scratch and kick violently, he puts this down to the DREADED RED MITE
which he compounded specially for this purpose, that,s from his book, if BILCO comes on site he will tell you about it and give some info, but i would try the harkers loft compound if you can get it, i always use colombovac floor white all the time. hope this helps,