My girls, too, have gone on strike. Thought for sure it was the heat and humidity (which is unusual for our area). So, gutted it up, told my customers wait a few weeks. Then this am, cleaned out the hen house. and went to get some bagged wood chips I have stored under an overturned water trough. Shock! More than two dozen eggs! The little devils had burrowed underneath it in the area between the trough and the fence where I couldn't see, and I hadn't overturned the trough in about two weeks. So, moral of the story: the heat is certainly a huge factor, but look for the less-obvious areas they could be laying. They are smarter - and more devious - that we think they are!