Difference between robbing and orientation

[applebwoi]

How can I tell for sure whether my bees are taking orientation flights or are being robbed? Every so often, usually around 6pm there is greatly increased activity around my hive. I don't see any obvious fighting and bees are not only flying around the hive entrance, but also up in the air. The heightened activity typically subsides after about 30 minutes and I've never seen it occur except in the late afternoon.I've always thought this was orientation flights, but just wanted to be sure I wasn't getting robbed. I'm feeding right now and the hive is going through about a quart every two days.

[Ron Young]

Sounds very similar to my hive. Check out the answers I recieved on the "Do I have Lazy Bees" post.