414 
THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123. No. 2, June 2011 
The Wilson Journal of Ornithology 123(2):414—416, 2011 
Botteri's Sparrow (Peucaea botterii ) Occurs in Northern Coahuila, Mexico 
Paul van Els , 13 Ricardo Canales-del-Castillo , 2 and John Klicka 1 2 
ABSTRACT.—Botteri's Sparrow (Peucaea botterii ) 
occurs widely in the shrub-grasslands of southern North 
America. We report a breeding population of the species 
in the Sierra de la Encantada of northern Coahuila, 
Mexico. —80 km from the Big Bend area of Texas and 
>300 km from the nearest previously known breeding 
range in southern Coahuila and central Chihuahua. We 
captured three individuals, which show a mostly gray 
dorsal coloration, suggestive of the te.xana subspecies, 
occurring from southern Texas to northern Veracruz, 
The exact affinity of the northern Coahuila population 
still needs to be ascertained. The presence of Botteri’s 
Sparrow in northern Coahuila may have been over¬ 
looked previously or may be part of a (temporary) range 
expansion. More work is needed to map the occurrence 
of Botteri's Sparrow in northcentral Mexico grasslands. 
Received 20 October 2010. Accepted 9 December 2010. 
Botteri's Sparrow (Peucaea botterii) occurs 
from southeastern Arizona through western Mex¬ 
ico to Nicaragua and from southern Texas to the 
Yucatan; the species also breeds in southern 
Coahuila (Howell and Webb 1995). The authors 
of the Coahuila State bird list mention Botteri’s 
Sparrow only as a migrant (Garza de Leon et al. 
2007). Occurrence in much of the northern part of 
the species' range is discontinuous because of 
fragmentation of natural shrub-grasslands due to 
overgrazing and agricultural conversion (Ripley 
1949, Webb 1985). However, despite expansion 
of intensive agriculture and ranching (Ceballos et 
al. 2010). there are still pockets of intact 
grasslands in northern Mexico that may hold 
populations of Botteri's Sparrow. Our objective is 
to describe a previously unknown population in 
northern Coahuila. Mexico. 
1 Marjorie Barriek Museum of Natural History, Univer¬ 
sity of Nevada Las Vegas, 4505 Maryland Parkway, Box 
454012, Las Vegas, NV 89154, USA. 
2 Laboratorio de Biologfa dc la Conservacion, Facultad 
de Ciencias Biologicas. Universidad Autonoma de Nuevo 
Leon, A. P. 25-F, Cd. Univcrsitaria, San Nicolas de los 
Garza. Nuevo Ledn 66451, Mexico. 
’Corresponding author; e-mail:paulvanels@yahoo.com 
OBSERVATIONS 
We surveyed the Valle Colombia ranch in (he 
Sierra de la Encantada of northwestern Coahuila 
(28 39'7.31" N, 101 20' 16.407" W) on 24-26 
June 2010. We found several singing male 
Botteri’s Sparrows, as well as young lacking tail 
feathers, a strong indication of local breeding. The 
Valle dc Colombia area consists of lightly grazed 
montane (1,350 m) native grasslands interspersed 
with Prosopis spp. (Fabaceae), Koeberlinia spi¬ 
nout (Koeberlinaceae), Flourensia cemua (Aslcr- 
aceae), Herberts trifoliolata (Berberidaceae), and 
local stands of Yucca spp. (Agavaceae). Winter 
shrub cover (x ± SD) varied locally from 1.28 ± 
1.12 to 6.68 ± 5.48% (January 2010). Sparrows 
were most frequently observed singing from the 
tops of Prosopis spp. We were able to capture 
three individuals, two males and a female, Birds 
were dissected to establish gender. Body mass 
(X * SD) was 19.8 ± 2.5 g, tarsal length was 20.5 
± 1.6 mm, wing length was 62.0 ± 0.6 mm, tail 
length was 60.6 ± 0.6 mm. bill length was 10.9 t 
0.4 mm, bill width was 5.8 ± 0.2 mm. and bill 
depth was 5.3 ± 0.1 mm. Dorsal coloration, die 
most variable character within the species (Web¬ 
ster 1959). was mostly gray with a profusion ot 
rufous streaks. W'e deposited a sound recording ol 
a male song from the Sierra de la Encantada in 
xeno-eanto (www.xeno-canlo.org, accession 
number XC57103). 
DISCUSSION 
Botteri’s Sparrow occurs rarely in southwestern 
Texas (Bryan 2002), and breeding of the species 
in northwestern Coahuila constitutes a northward 
shift in the central part of the known range of the 
species by >300 km. Northern Coahuila is poorly 
sampled omithologically and our records ot 
Botteri’s Sparrow in the Sierra de la Encantada 
may only represent a fraction of the specif' 
population in the region. Suitable, intact grassland 
habitat may be present elsewhere in this area, 
including potentially Texas, only 80 km from lhc 
current population. The occurrence of a small- 
now possibly extinct population in central Chi- 
