Is this Nasonoving?

[Twisted T]

I think it is but wanted to check.

[Aroc]

Could be....could also be fanning to cool down the hive.  This time of year you will see more of that.

[AR Beekeeper]

Fanning to cool the hive, the abdomen is curved downward and no Nasonov gland is exposed.  When the bees are fanning to show the hive location the abdomen is curved upward with the very last segment pointing down and the gland opening can be seen.

[Twisted T]

I wish that I could post the video that I took. At first I thought they might be fanning, but they we not beating their wings. Fairly stationary with their rumps in the air. The pic was taken a couple of weeks ago and everything appears to be ok with them now.

[tjc1]

From what I understand, they only nasonov for a reason, as in when the hive has been disturbed and they feel they need to help other bees relocate the hive.

[BeeMaster2]

I agree with the rest, no gland showing. When they are doing it they are also fanning to spread the lemongrass scent.
The picture looks like they were all facing down. Were they actually facing up?
If so, they may have been hit by mosquito spraying.
Jim

[Michael Bush]

They are upside down, of course, but from the bee's orientation their butt is down, rather than up.  When they nasonov, as others pointed out, they expose the gland by curling their butt up (from the bee's point of view).  The nasonov gland is kind of red.  See the bee in the center here who is exposing her nasonov gland:
http://www.bushfarms.com/images/Nasonoving.jpg