They will, and to a hive that you may think is strong. Last fall I lost a hive that had been a big hive. When out to check on yard and they were all robbing the one, the hives were on a concrete slab, dead bees everywhere. Had another one this spring. I found the one this spring early in the robbing closed the hive almost completely, left an entrance of about 3/4 X 3/4 in. They were still finished the next day. Hope you have better luck.