Identifying robbing

[kmartin]

I a weaker colony is being robbed, is there always conflict at the entrance?

[Curtis]

If the weaker colony's entrance has been reduced, and robbing is going on there should always be conflict at the entrance.
Also don't confuse robbing with just keeping out Drones.
Curtis

[Michael Bush]

>is there always conflict at the entrance?

Not necessarily.

http://www.bushfarms.com/beesrobbing.htm

[sierrabees]

It seems like a weak hive will sometimes seem to just give up if the robbing is intense. I think that if all the guard bees are used up (killed by losing their stingers defending the hive) the rest of the bees are not inclined to mount a defense. This could happen with a critter (skunk, coon, or beekeeper) pestering the hive too much and putting a drain on the supply of guard bees.
From what I have read, appearantly a worker only serves guard duty one or two days in their life and after that they only attack when stimulated to do so by the pherimones released by an upset guard bee, and then only when not preoccupied with their other job description.