Humid, muggy, hot, wonderful south Alabama. The hot spot and place to be for all jet-setting small hive beetles... :roll:
So far I've been blessed with a minimum number of beetles in my hives. I have 2-3 Beetle Jail Jrs in each of my three hives and I'm catching several beetles in them. I normally see/kill maybe a half dozen beetles cumulatively in the three hives when I do inspections. Yeah, I'm happy. BUT...I know one day the honeymoon will end.
I'm pretty sure that I'm re-inventing the wheel, but here goes...
Most of my woodenware is from Rossman (one day I do hope to set up a small woodshop). I measured the screened bottom boards and there is 3/8" space from the cement blocks to the bottom surface of the bottom board. I'm thinking of adding a strip of 3/8" wood to the front of the bottom boards (on the bottom) maybe 1/2" beyond where the screen ends at the porch...this would block the front off to the bees. Removal of the tray will be from the rear.
Next, I could make a tray from either aluminum flashing or if I feel gungho I could use galvanized sheet metal...or maybe a cookie sheet if I could find the right size. Or even a sheet of coroplast with a thicker grease smeared on it (it's election year so stock up!!!! :-D ) If I make a metal tray it will have to be shallow lipped. The end toward the back I'm thinking of attaching a strip of 3/8" wood to to give it more rigidity and act as a handle. This wood piece would be cut so as to seal the back of the tray area from the bees. A thin layer of mineral oil or other non-toxic oily substance covering the tray should be good enough to trap/smother/drown anything as big as a beetle (mites wouldn't have a chance). I did not measure it, but I'm guessing the bottom of the tray would be 1" below the screened bottom board.
With this design there would be no support beneath the trays except at the edges where the cement blocks are so I'm thinking galvanized sheet metal will be better than aluminum flashing...the coroplast should be rigid enough. There will be some end support at the back created by the 3/8" wooden "drawer front" spanning between the cement blocks. I guess if it was needed some support strips could be epoxied to the bottom of the trays to give some support/rigidity.
I have also thought of building an opened topped box with house screening on the bottom, closed at the front, and a hinged or slide-in door at the rear. Side rails of 2x material to give it some height. This would be placed beneath the existing screened bottom board. An oil tray could be slipped into the compartment that is created and the door closed...this would effectively block off beetle/moth entry via the bottom board (house screen). Ventilation would still be maintained (probably decreased some). An added benefit would that this might act as a buffer zone for the bottom areas of comb and encourage the queen to lay lower down in the comb.
Anyhow, just some half-baked ideas regarding dealing with trapping beetles that are probably already being used somewhere. :)