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Pale-throated Serra-finch Embernagra longicauda

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Pale-throated Serra-finch Embernagra longicauda
Cotinga 16
P a l e - t h r o a t e d S e r r a - Fin c h Em bernagra longicauda
A u s t r a l R a il Rallus antarcticus
Mangabeiras Municipal Park5, Protected Area of
Barreiro12, Protected Area of Mutuca12, Peti Re­
serve5, Caraça Reserve2,3,6, Itacolomi State Park1,6,12,
and Protected Area of São José5. It is probable that
E. longicauda will also be found in other areas of
suitable habitat, such as the recently created state
parks of Grão Mogol, Pico do Itambé and Rio Preto,
in Minas Gerais.
P a le - t h r o a t e d S e r r a - Fin c h
Embernagra longicauda
Pale-throated Serra-F
i n c h Embernagra longicauda
is endemic to the Espinhaço range9,10, in the states
of Minas Gerais and Bahia, Brazil. It resembles its
close relative, the Great Pampa-F
i n ch E. platensis.
However, Pale-throated Serra-F
i n c h is easily recog­
nised by its longer and narrower tail, grey head,
white supraloral streak and lower eyelid, and white
throat8. The two species can be found in the same
area, but do not overlap in habitat; Pale-throated
Serra-Finch generally occurs in dry open areas,
sometimes with rocky outcrops, whereas Great
Pam pa-Finch prefers m arsh lan d s and damp
places6,8,11. Voice is a penetrating tsi-tsoweeé8, given
throughout the day, even in the hottest hours (pers.
obs.).
It inhabits mainly open habitats in the moun­
tains, including campos rupestres, campos cerrados
and campos limpos, generally above 900 m6,9,12. Palethroated Serra-F
i n c h even occurs on the highest
peaks of the Espinhaço; the individual in Fig. 1 was
photographed at Pico do Inficionado, at 2050 m, in
the Serra do Caraça, Minas Gerais. The birds for­
age on the rocky outcrops, and in short trees and
shrubs, including canelas-de-ema (Velloziaceae), for
small invertebrates and seeds. Occasionally two feed
together6. Breeding occurs in the rainy season and
the nest is cup-shaped, with two nestlings being the
usual clutch6.
Recently, E. longicauda has been discovered in
degraded open habitats, such as deforested areas
with rocky outcrops and second growth, away from
natural fields in the Espinhaço5,11. This is possibly
related to its geographic expansion, resulting from
deforestation in these localities, where there were
once large areas of Atlantic Forest5,11.
Despite being endemic to a restricted area9,10
and being considered near-threatened4, Machado et
al.5 suggest that E. longicauda should be treated
within a lower risk category, because it is appar­
ently expanding its range and occurs in a significant
number of protected areas. Machado et al.5also state
that the species’ habitats are subject to low human
degradation, but I disagree: campos rupestres have
been destroyed by mining activities (principally in
the southern Espinhaço), by periodic fires in the dry
season and by cattle-grazing.
In Bahia, Pale-throated Serra-F
i n ch can be found
in Chapada Diamantina National Park6,7. In Minas
Gerais, the species occurs in a number of protected
areas, including Serra do Cipó National Park3,6,
A c k n o w le d g e m e n ts
I thank CAPES, WWF and USAID for financial sup­
port during my masters course.
R e fe re n c e s
1. Andrade, M. A. (1998) O Parque Estadual do
Itacolomi e suas aves. Uiraçu 2: 4.
2. Carnevalli, N. (1980) Contribuição ao estudo da
ornitofauna da Serra do Caraça, Minas Gerais.
Lundiana 1: 89–98.
3. Carnevalli, N. (1982) Embernagra longicauda
Strikiland [sic], 1844; sua ocorrência em Mi­
nas G erais– B rasil (Aves, Fringillidae).
Lundiana 2: 85–88.
4. Collar, N. J., Crosby, M. J. & Stattersfield, A. J.
(1994) Birds to watch 2: the world list o f threat­
ened birds. Cambridge, UK: Birdlife Interna­
tional (Conservation Series 4).
5. Machado, R. B., Rigueira, S. E. & Lins, L. V.
(1998) Expansão geográfica do canário-rabudo
(Embernagra longicauda —Aves, Emberizidae)
em Minas Gerais. Ararajuba 6: 42–45.
6. M attos, G. T. & Sick, H. (1985) Sobre a
distribuição e a ecologia de duas espécies
crípticas: Embernagra longicauda Strickland,
1844, e Embernagra platensis (Gmelin, 1789).
Emberizidae, Aves. Rev. Brasil. Biol. 45: 201–
206.
7. P arrini, R., Raposo, M. A., Pacheco, J. F.,
Carvalhães, A. M. R, Melo Júnior, T. A.,
Fonseca, P. S. M. & Minns, J. C. (1999) Birds of
the Chapada D iam antina, Bahia, Brazil.
Cotinga 11: 86–95.
8. Ridgely, R. S. & Tudor, G. (1989) The birds of
South America, 1. Austin: University of Texas
Press.
9. Sick, H. (1997) Ornitologia brasileira. Rio de
Janeiro: Ed. Nova Fronteira.
10. Silva, J. M. C. (1995) Biogeographic analysis of
the South A m erican cerrado avifauna.
Steenstrupia 21: 49–67.
11. Vasconcelos, M. F. (2000) Ocorrência simpátrica
de E m b erizo id es h erb ico la , E m b ern a g ra
p la te n s is e E m b ern a g ra lo n g ica u d a
110
Cotinga 16
Photospot
(Passeriformes: Emberizidae) na região da
Serra do Caraça, Minas Gerais. Melopsittacus
3: 3–5.
12. Vasconcelos, M. E, Maldonado-Coelho, M. &
D urães, R. (1999) N otas sobre algum as
espécies de aves ameaçadas e pouco conhecidas
da porção meridional da Cadeia do Espinhaço,
Minas Gerais. Melopsittacus 2: 44–50.
M arcelo Ferreira de V asconcelos
Pós-Graduação em Ecologia, Conservação e Manejo
de Vida Silvestre, ICB, Universidade Federal de
Minas Gerais, Av. Antônio Carlos, 6627, C.P. 486,
30161-970, Belo Horizonte, MG, Brazil. Current ad­
d re ss: R ua P araíba, 740, a p a rta m e n to 501,
30130-140, Belo Horizonte, MG, Brazil. E-mail:
[email protected]
A u s t r a l R a il
Rallus antarcticus
sheep grazing, and the animals can enter the
rushbeds as the water is largely frozen. This prac­
tice may represent a key threat to the species’
habitat. No rails have been recorded in southern
Santa Cruz and neighbouring Chile during July to
September, when most marsh vegetation dies until
regrowth in September–October.
These first photographs were taken at El Zurdo,
Santa Cruz, Argentina (51°59'S 71°41'W), in May
1999, during one of the rare occasions in which in­
dividuals stalked from the cover of the dense rushes.
They were lured out using tape playback, briefly
appearing inquisitively. They spent most time re­
sponding to the tape from concealed, tunnel-like,
cavities within the rushes. This continued for over
90 m inutes after midday, in clear and sunny
weather, when the rails appear to prefer to remain
in cover.
R e fe re n c e s
With only five records in the 20th century and 19
since its discovery, the status of Austral Rail was
completely unknown until a small population was
discovered in central Santa Cruz, Argentina in
19984. Little was known concerning its biology and
numbers and, in consequence, it was classified as
Endangered/Extinct (possibly extinct)2. The discov­
ery was significant in that it represented the first
known population and provided baseline data to
search for and study the biology and habitat require­
ments of the species.
It inhabits marshy oases, within Patagonian
steppe, dom inated by rushes Schoenoplectus
(Scirpus ) californicus and usually surrounded by
wet meadows with tall, lush grasses, including
Ceratophyllum sp., Carex sp., Alopecurus sp. and,
predom inantly,
D escheupsia
p o a e io id e .
Myriophyllum sp. usually covers more open areas.
The rail has not been recorded in marshes within
southern beech (Nothofagus sp.) forests, despite
their similar structure and species composition.
Using tape-recordings, further areas of appro­
priate habitat have been successfully surveyed since
the rediscovery: new populations have been found
at several localities in southern Santa Cruz5 and
neighbouring Chile1,3, and its vocal repertoire bet­
ter documented. The Chilean records are important
as they are from the only protected areas where the
species occurs, namely Pali Aike and Torres del
Paine National Parks1. Given that the species had
apparently been overlooked, it was recently
downlisted to Vulnerable, under IUCN’s criterion
C2a (population <10 000 mature individuals with
continuing decline and all subpopulations <1000
individuals)1.
Its wintering grounds are unknown, but there
is some evidence for at least local movements. At
this season, most farms with suitable habitat use
the species’ favoured marshy areas for cattle or
1. BirdLife International (2000) Threatened birds
o f the world. Barcelona: Lynx Edicions & Cam­
bridge, UK: BirdLife International.
2. Collar, N. J., Gonzaga, L. R, Krabbe, N., Madroño
Nieto, A., Naranjo, L. G., Parker, T. A. & Wege,
D. C. (1992) Threatened birds o f the Americas:
the IC B P /IU C N Red Data Book. Cambridge,
UK: International Council for Bird Preserva­
tion.
3. Imberti, S. & Mazar Barnett, J. (1999) El piden
austral R allus antarcticus redescubierto en
Chile. Bol. Chil. Orn. 6: 44–45.
4. Mazar Barnett, J., della Seta, M., Imberti, S. &
Pugnali G. (1998) Notes on the rediscovery of
the Austral Rail Rallus antarcticus in Santa
Cruz, Argentina. Cotinga 10: 96–101.
5. Mazar Barnett, J. & Imberti, S. (1999) New in­
formation on the ecology, distribution and sta­
tus of the Austral Rail (Rallus antarcticus ) in
Argentina and Chile. In Libro de Resúmenes,
VI Congreso de Ornitología Neotropical,
Monterrey y Saltillo, octubre 1999.
S antiago Im berti and Pablo Sturzenbaum
CC: 368, (9400) Rio Gallegos, Santa Cruz, Argen­
tina. E-mail: [email protected]
Ju an M azar B arnett
Av. Forest 1531 1 °B, (1430) Buenos Aires, Argentina.
111
Cotinga 16
Photospot
Pale-throated Serra-Finch Embernagra longicauda (M arcelo Ferreira de Vasconcelos)
A ustral Rail Rallus antarcticus (Pablo Sturzenbaum)
112
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