Bulletin - United States National Museum - si-pddr - Smithsonian ...

BIRDS OF ARGENTINA, PARAGUAY, URUGUAY, AND CHILE 57
meter 182, Formosa, on August 9 and 14, and an adult pair at
Kilometer 80 on September 10.
These herons were noted in small numbers in the Chaco, where
they frequented open marshy lagoons and the borders of esteros.
Frequently they walked about on masses of floating vegetation where
the water Avas a meter or so deep, or stalked slowly about pools in
wet meadows. They were wary and, as they fed in the open, difficult
to approach. They fly with a peculiar short stroke of the wing
that is highly characteristic, and in flight appear dull gray, with
light tail and duller forepart of body, so that when a fallen bird
is retrieved the beautiful, blended colors of the plumage come as a
sharp surprise. Their alarm note is a harsh quah-h-h quah-h-h,
resembling that of other herons, but in addition they give a shrill
whistled note that is repeated frequentl3^ The latter call I heard
only from birds that were flying, and noted that, as it was given, the
neck was outstretched, to be retracted as the whistling was finished.
A pair observed in display about a small pool, on September 24,
flew swiftly back and forth and then set the wings to sail rapidly
in short circles while they turned first one side and then the other
to show alternately the dark back and the light breast. The performance
was executed with a dash and speed that would have done
credit to a duck and reminded me in a way of the darting maneuvers
executed at times by shore birds.
In the Chaco the whistling heron was observed as far west as
Laguna Wall, 200 kilometers west of Puerto Pinasco, on the Paraguay
River. Occasional individuals were seen from January 24 to
February 2 at San Vicente, in the Department of Rocha, eastern
Uruguay, where I found them at times walking about in dry fields
in search of the abundant grasshoppers. Others were noted at
Lazcano, February 6, 8, and 9, and one Avas seen at Rio Negro,
Uruguay, February 16.
The species is knoAvn as garza chifflon or simply as chifflon. The
Toba Indians called it -pilK' la tse de, while the Anguete knew it by
the impressive cognomen of pat gwa zhi gwa Tiiohh. Indians occa-
sionally offered the plumes of the wing coverts and nape for barter.
CASMERODIUS ALBUS EGRETTA (Gmelin)
Ardea egretta Gmexin, Syst. Nat., vol. 1, pi. 2, 1789, p. 629. (Cayenne.)
Two adult egrets were seen near Kilometer 80, west of Puerto
Pinasco, Paraguay, on September 13, 1920, and four were observed
at Carrasco, near Montevideo, Uruguay, on January 16, 1921, a sad
commentary on the present status of a bird once found in abundance
throughout southern South America. Breeding colonies were re-
ported on the Rio Pilcomayo and near the Rio Cebollati in eastern
Uruguay. In Argentina herons are protected and traffic in their