What these covers consist of is basically a finely screened inner hive cover with a couple inch space and lots of ventilation holes. This is then covered with a standard hive cover. While this may have worked, I don't think the bees really appreciated the ventilation as they pretty much sealed the screening with their thick gluey propolis which negates the ventilation aspect.
Now the downside of these little ventilated chambers is they also act as a penthouse suite for all sorts of critters. There have been black widow spiders in the past, lizards, and yesterday one penthouse suite contained three FROGS !!!. In another penthouse suite I found many white eggs?? from god knows what. I posted the picture on a very large beekeeper facebook group and received dozens of replies (guesses) but one person in the pacific northwest was pretty sure they were wax moth cocoons. Most people thought they were lizard eggs which is a possibility since I've found lizards up there also. But the eggs seemed to be the wrong shape for lizard eggs and they were too small. A couple people even guessed tic tacs : ) I wasn't about to taste one and find out.
|mystery eggs in the ventilated hive cover|