Hmm, I hadn't thought of that (not that I didn't know it)--that the season between Thanksgiving and Christmas is the busiest for most academics (at least in the U.S.).
Perhaps, then, we shouldn't actually try to do so much recruitment in the next few weeks. I mean, we might have more luck in January. What do you think?
Finding a down time will always be hard. There are grant deadlines all over the place in January. I would say the only really quiet time is end of May and early June. The summer is full on conferences or field work, so even that can be a busy time.