>To whom it may concern:
>
>I recently visited Puerto Lobos in Northern Sonora Mexico.  While on the
>dunes near the ocean I observed a bee building a tunnel in the sand.  I
>believe it is Hemesia (=Centris?) sp.  If anyone is interested in knowing
>about the behavior I observed or has any suggestions as to how to locate
>detailed info on this nest?/tunnel building behavior please let me know.
 
Gordon Frankie and Brad Vinson have examined nesting behavior of such
Centris, and Dave Roubik and I studied a species nesting on an island in
the Panama Canal; the former work is published, though I can't seem to
locate my reference in a quick scan here (I think two pertinent refs are in
J. Kansas Ent. Soc. 53: 837 and 60: 249), and as far as I know the latter
study is not. The behavior itself, then, is clearly known, but not
necessarily for the species you encountered (which is more in Roy
Snelling's neck of the woods, and he might be a person to contact).
Cheers,
 
Doug Yanega       Illinois Natural History Survey, 607 E. Peabody Dr.
Champaign, IL 61820 USA      phone (217) 244-6817, fax (217) 333-4949
 affiliate, Univ. of Illinois Urbana-Champaign, Dept. of Entomology
  "There are some enterprises in which a careful disorderliness
        is the true method" - Herman Melville, Moby Dick, Chap. 82