"The use of signal communication in
WWI was extensive and the tasks of the Signal Corps varied. Some of the tasks were: radio,
telephone, photographic, pigeon and other special services.
The pigeon service did not exist in the American Army prior to WWI. Experiments on the
Mexican border had been unsuccessful due to the inexperience of the personnel handling the
birds. However the Chief Signal Officer of the American Expeditionary Force (A.E.F.)
recommended the establishment of a pigeon service as a branch of the Signal Corps and it
was quite successful. In the Meuse-Argonne offensive, a total of 442 American birds were
used and approximately four hundred messages were delivered."
http://www.cix.co.uk/~mhayhurst/jdhayhurst/pigeon/pigeon.html
The Pigeon Post into Paris 1870-1871
by J.D. Hayhurst O.B.E.
http://interbug.com/pigeon/two_way
An article from the December 1977 issue
of The Pocket Pigeon regarding the Army's method of training pigeons for two-way
messenger service.