Got a situation, never had before in all my years of keeping bees. I keep all my hives on screen floored, sliding bottom boards. Sliding bottom boards kept closed except for inspections(mite drop, etc.). One hive has continuing excessive amounts of dark brown feces on the sliding board. I've had cases of dysentery periodically over the years and this isn't like them. No feces anywhere on the outside of the hive. I don't find feces on the frames or anywhere else in the hive. No discernible odd odors in the hive. The hive appears normal with all usual healthy activities. The feces spots on the sliding board are spread evenly across board, not in rows as if falling from bee spaces between frames. I have my hive entrances reduced considerably at this time of the year because of wasp and robbing threats. One thing I have learned about these critters is- I will see stuff I've never seen before no matter how long I keep them. At this point I'm guessing, with this tiny entrance on a large colony, they are just crapping on the screen floor because it's easier then exiting the hive. Tell me where I'm wrong or whatever theory you might have or insights. I don't feel it's the end of the world, just something I've never seen before.