Honey bee swarms almost always travel rather near the ground and are
easily seen as they move through an area.
 
   Drone congregation areas are usually high enough in the air (~above 10
meters) so that the individual drones cannot be seen unless they pursue
some object as it descends lower.  These aggregation areas can be detected
by the hum of insects aloft that seems to have no center.  I always
demonstrated their existence (in mid afternoon) to my students by bringing
along a slingshot and lobbing stones up into the air.  The students could
then see a comet of drones descending into view as they chased the stone.
 
                                                        Adrian
 
 
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* Adrian Wenner        E-Mail   [log in to unmask]  *
* Department of Biology        Office Phone    (805) 893-2838 *
* University of California     Lab Phone       (805) 893-2838 *
* Santa Barbara, CA  93106     FAX             (805) 893-4724 *
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