u can also buy wd40 by the gallon get u a pump up sprayer and spray the coop from one end to the other this will take care of the bugs and any eggs they have layed but u have to spray every little spot u can also spray the birds but u don't want to spray but just a little on them at there vent...
its probably an owl they would come in from the sky so unless ur camera was pointing into the air u want see him on camera or catch him in a trap on the ground and the mud since he flies he can land on the roost pole sticking out of the cage or land on the side and hold on with one foot and...