I think that bees might use small concentrations of CO2 as an indicator of an animal
intruder.  Many other insects, such as mosquitos, black flies, and tsetse flies,
actually locate their prey through their CO2 emissions, as well as colour and traps for
these insects are based on that behavior.   This might explain the effect between the
tube breathing and AHB behavior.
 
Chris Allen wrote:
 
>
> Before you get too worked up about this, talk to a few queen breeders about CO2.
>
> CO2 is used to drug virgin queens for artificial insemination.  I believe
> CO2 is generally recognized as sedating most insects.  One queen breeder
> said that for a ** REALLY SAVAGE ** colony, a squirt of CO2 from a soda
> siphon would settle them down.
>
 
> Chris Allen