Centro de Estudos de Migraes de Aves (CEMAVE) Caixa Postal 04/034, BrasiliaFCep. 70.312, BRASIL
The South American Pochard (Netta erythrophthal-
ma erythrophthalma) is a little known pochard, spot-
tily distributed in Venezuela (Caribbean coast), Co-
lombia (Caribbean coast, temperate zone of the
Eastern Andes, the southeast, and Cauca Valley),
southeastern Ecuador, Peru (west of the Andes),
northern Chile, northern Argentina, and sporadic-
ally in eastern and northeastern Brazil (Meyer de
Schauensee 1966). In Brazil it has been collected in
Belmonte (Bahia, 15ø51'S, 38ø54'W), Lagoa da Ribeira
(Rio de Janeiro, 22ø08'S, 41ø28'W) (Coimbra-Filho
1969), and Baturit (Cear, 04ø20'S, 39ø00'W). (Spec-
imens are in the Museu de Zoologia da Universidade
de So Paulo). The ecology and biology of the South
American Pochard are almost unknown.
On 8 August 1980, while banding waterfowl at
Santa Maria reservoir, we saw 100 South American
Pochard for the first time in central Brazil. The 825-
ha reservoir is in the middle of the Brasilia National
Park (15ø40'S, 47ø50'W) at an altitude of 1,100 m.
Dammed in 1970, it was formed by the Barriguda,
Vargem Grande, and Milho Cozido Rivers. It is sur-
rounded by cerrado vegetation and has swampy
vegetation only at the mouths of the rivers. The water
level is variable because of the well-marked dry (May-
September) and rainy (October-April) seasons. South
American Pochards, Brazilian Teal (Amazonetta bras-
iliensis), White-faced Tree-Ducks (Dendrocygna vi-
duata), Black-bellied Tree-Ducks (D. autumnalis),
sandpipers, and other water birds use the reservoir
year round or seasonally. Only the Brazilian Teal and
the Pied-billed Grebe (Podilymbus podiceps) breed
there. The reservoir has been regularly mist-netted
since July 1979.
The first flock of pochards was seen on 8 August
1980 along the shore of the reservoir at 1400. Most
were sleeping or preening; a few were feeding in 20
cm of water near the shore. Between 100 and 150
pochards of both sexes were seen in the same place
on 30 August, 3 September, and 13 September 1980.
They disappeared after 13 September 1980. On 22
February 1981, between 0430 and 0600, several flocks
of pochards were seen at the reservoir, flying west
to east close to surface of the water. All flocks num-
bered between 50 and 100 birds. A male was netted
in the Milho Cozido River mouth and banded with
CEMAVE band number S-00511. It was in full adult
plumage, and its iris was deep red. When released
in the water, the male dove instead of taking flight,
the normal escape behavior of the other duck species
banded. Each dive was about 50 m long and lasted
20 s. The male wasn't damaged by the net, and its
remiges were fully grown.
On 4 April 1981, 20 pochards were seen at the res-
ervoir. Eight were molting the remiges and could not
fly. On 13 June 1981, at the mouth of the Barriguda
River, five males and two females were seen; all were
in wing molt. Four of six males, collected on 3 and
6 August 1958 in Baturit, Cearh and housed in the
Museu Paulista de Hist6ria Natural, were molting
the remiges (pers. obs.). These data indicate great
variation in the timing of wing molt in the South
American Pochard.
We suggest that the southern Pochard has colo-
nized the Central Brazilian Plateau by expanding its
range from southeastern coastal Brazil. The new res-
ervoirs constructed in the Paranh and So Francisco
basins have furnished new habitat suitable for these
species, as, for example, that of the Brasilia National
Park reservoir.
We thank the Departamento de Parques Nacionais
do Instituto Brasileiro de Desenvolvimento Florestal
and the director of the Brasilia National Park for per-
mits and support and Dr. Paulo Emilio Vanzolini,
Director of the Museu de Zoologia da Universidade
de So Paulo, for the permission to examine speci-
mens. We thank Philip S. Humphrey for his correc-
tions on our first English text.
LITERATURE CITED
COIMBRA-FILHO, A. F. 1969. Sobre a ocorrncia de
Anas discors Linn6, 1776 e de Netta erythro-
phthalma (Wied, 1832) no Estado do Rio de Ja-
neiro, Brasil (Anatidae, Aves). Rev. Bras. Biol.
29: 87-95.
MEYER DE SCI-IAUENSEE, R. 1966. The species of
birds of South America and their distribution.
Wynnewood, Pennsylvania, Livingston Publ. Co.
Received 2 February 1982, accepted 18 May 1982.