A hard lesson I would like to share with you.
When I did my site inspection a couple of weeks ago I was shocked to see a large number of bees floating in the rapid feeder. The lid was still on the feeder and the inner-cup was still on. But the lid of the feeder was slightly skew and at that time the crown board still had an open hole.
The bees had come-up from the crown board and climbed-up the exterior of the rapid feeder and entered the feeder through the slight gap in the skewed lid. The bees were attracted to the syrup and drowned in the process.
In this situation, it was a case of rescuing any bees I could and removing the feeder from the hive to dispose of the dead bodies and syrup. A new feeder replaced it later.
I have also had ants visit my feeder as well.
Moral of the story:
Once you have finished topping-up the rapid feeder be mindful to give the lid a firm push. Simple as that!