I have a strong hive from which I harvested all 6 frames in late Jan / early Feb. Before doing a 2nd lot of harvesting I inspected the hive and found a couple of hundred dead bees on top of the crown board. The hive is still strong and there were no issues in the brood box. There were no more than the odd dead bee outside the hive. I’ve been advised by my bee club mentors that the area above the crown board is considered by the bees to be outside the hive and that they may be dumping deaduns there using the short cut. Have any others had this experience?
Hiya Bob, welcome to the forum.
I had the same issue a while ago and at the time I thought the bees had got stuck there and died however the depositing of dead uns did cross my mind. Regardless I always keep the feeding hole shut up nowadays and don’t have the issue anymore. 
Hi Bob,
As Skeggley said, welcome to the forum. I would second what he said n your mentor. I’ve never had that issue up here near Seattle because all my crown board holes are screen so no access (a brick or flat object work great too)… I keep mine screen for ventalation in our because Puget Sound region is so damp/wet thus leaving it open but screen.
I’d just bush out the old dead bees, cover or screen (your choice) n see if like Sheggley the issue completely disappears. It seems you n your mentor have covered other reasons for dead bees.
Good luck n happy Beekeeping 
Gerald
Hi Skeggley & Gerald
thanks for the comments. I inspected again today and there were no dead
bees on the crown board. I have now patched the hole as I had planned to do
because the bees had also built lots of burr comb under the roof in early
Spring - so 2 good reasons to cover the hole.
Bob
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