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

150 BULLETIN 133^ UNITED STATES NATIONAL MUSEUM
that might contain 100 individuals. On their wintering grounds
they were rather silent, but with the opening of northward migration
resumed their habit of uttering musical though noisy calls when
disturbed in any manner. On the pampas they congregated during
drier seasons about lagoons and flocks often sought refuge from the
violent winds that swept the open plains behind scant screens of
rushes. After any general rain these flocks dispersed to pools of
rain water in the pastures, where insect food was easily available.
The winter population was thus not stationary, but shifted con-
stantly with changes in the weather. By the first of March the
lesser yellowlegs had begun their northward movement and numbers
were found near Guamini, where they paused to rest after a northward
flight from Patagonia. In their case, as in that of other
migrant species from North America, it was instructive to note that
the migration southward came in September and October when the
birds traveled southward with the unfolding of the southern spring
and that the return northward was initiated by the approach of
rigorous weather in faraway Patagonia. Migrant flocks, many of
whose members offered sad evidence of inhospitable treatment at the
hands of Argentine gunners in the shape of broken or missing legs,
were noted on the plains of Mendoza, near the base of the Andes, in
March. And during early April the migration became a veritable
rush so that on the night of April 5, at Tucuman, the air was filled
with the cries of these and other waders in steady flight northward
above the city.
The lesser yellowlegs seems to undergo a complete winter molt
while in the south. Two females secured September 6 and 21 at
Kilometer 80, Puerto Pinasco, Paraguay, have both body and flight
feathers worn. A female from Lazcano, Uruguay, taken February
7, is renewing the two outermost primaries in either wing. The
other primaries, the secondaries, and the tertials, as well as the wing
coverts, are new feathers, and the body plumage is in process of
renewal. Another female killed at Guamini March 8 has the wing
feathers entirely replaced and new plumage appearing on the body.
Like the greater yellowlegs, Totanus flavipes has been reported in
Argentina from May to August, but it must be assumed, on the basis
of crippled individuals.
The generic relationships of this species have been discussed in the
account of its larger brother T. nielamoleucus.
TOTANUS MELANOLEUCUS (Gmelin)
Scolopax melanoleuca Gmelin, Syst. Nat., vol. 1, pt. 2, 1789, p. 659. (Chateau
Bay, Labrador.)
The generic relationship of the two yellowlegs to one another and
to related shore birds has been subject to considerable difference of