Stan Sandler commented quite perceptively about bees and water sources.
In our adventures on Santa Cruz Island, we found bees usually collected
water from some quite "raunchy" sources.  An algae coated seep on a rock
face proved especially attractive.  The algae covered stones at the edge of
streams was another.
 
   For some years I have advocated floating a burlap bag on boards on top
of the water surface provided for bees.  In time that burlap gets infused
with algal cultures.  It seems that bees need an odor source that they can
associate with a water source.
 
   And, yes, the minerals may be quite important.  Male butterflies of some
species ingest water from muddy sources, pass it through their bodies, and
thereby concentrate the minerals.  They apparently later pass those
minerals on to the females during copulation --- thus enhancing nutrition
of the resultant eggs.
 
                                                        Adrian
 
Adrian M. Wenner                         (805) 893-2838 (UCSB office)
Ecol., Evol., & Marine Biology           (805) 893-8062  (UCSB FAX)
Univ. of Calif., Santa Barbara           (805) 963-8508 (home office & FAX)
Santa Barbara, CA  93106
 
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*  "Discovery is to see what everyone else has seen,                  *
*         but to think what no one else has thought."                 *
*                                       ---    Albert Szent-Gyorgyi   *
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