I've noticed a couple of hives do this washboard movement both on the front of the hive and the landing board. Possibly they are just bored? Kathy Cox, Northern California, Italian, 17 hives :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: -- Visit www.honeybeeworld.com/BEE-L for rules, FAQ and other info --- ::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::