The Wilson Journal of Ornithology 123 ( 1 ): 137 - 141 , 2011 
NESTING BIOLOGY, HOME RANGE, AND HABITAT USE OF THE 
BROWN WOOD RAIL (.ARAMIDES WOLFF) IN NORTHWEST ECUADOR 
JORDAN KARUBIAN, 1 ’ 4 LUIS CARRASCO, 2 PATRICIO MENA, 2 JORGE OLIVO, 2 
DOMINGO CABRERA, 2 FERNANDO CASTILLO, 2 RENATA DURAES, 1 AND 
NORY EL KSABI 3 
ABSTRACT.—The Brown Wood Rail {Aramides wolfi ) is a globally threatened, poorly known species endemic to the 
Chocorain forests of South America. We provide a first report on the species nesting biology, home range, anc la i a 
Nests (n = 16) were open cups ~2 m above ground and were more common in secondary forest than expected by chan : . 
Median clutch size was four eggs, incubation lasted >19 days, the precocial young departe t e nest wi in 
hatching, and 66% of nests successfully produced young. At least two adults participated in parenta care anc pair 1 
appear to be maintained year-round. The home range of an adult radio-tracked for 7 months was .. ia in s ^ on fT 
selectively-logged forest contiguous to primary forest. This easily overlooked species may e more resi icn o 
levels of habitat degradation than previously suspected, but extensive deforestation throughout its range justifies 
status as ‘Vulnerable to Extinction’. Received 24 February 2010. Accepted 28 July 2010. 
Twenty species of Rallidae have become 
extinct since 1600, and 33 of the remaining 133 
extant species (24%) are currently globally 
threatened (Taylor 1996). Cryptic habits compli¬ 
cate adequate assessment of conserv ation require¬ 
ments for many of these species (BirdLife 
International 2000). For example, population size, 
conservation status and, in some cases, even 
geographic distribution of the six species of Wood 
Rail that comprise the South American genus 
Aramides are currently unclear (Taylor 1996). 
Aramides Wood Rails are relatively large, 
primarily terrestrial birds that favor more wooded 
environments than many other rails (Ridgely and 
Greenfield 2001). Four members of the genus are 
thought to be globally threatened (Taylor 1996), 
including the Brown Wood Rail ( Aramides wolfi). 
This species is distributed at lower elevations 
a I°ng the western slope of the Andes in Colombia, 
Ecuador, and perhaps Peru (BirdLife International 
2000). It is recorded from streams and swampy 
areas inside humid forest and secondary wood- 
iands (Ridgely and Greenfield 2001). The Brown 
^ood Rail is reclusive, hard to observe, and 
vocalizes infrequently; its basic biology remains 
poorly known. Widespread habitat destruction 
w ithin its range (Sierra 1996, Conservation 
International 2001) and its apparent absence from 
Department of Ecology and Evolutionary Biology, 
Llane University, 400 Lindy Boggs Center, New Orleans, 
LA 70118, USA. 
Center for Tropical Research, Rumipamba Oel41 y 10 
Agosto, Quito, Ecuador. 
’51 rue de Nantouar, 22660 Trelevem, France. 
Corresponding author; e-mail: jk@tulane.edu 
many localities (Ridgely and Greenfield 2001), 
have caused it to be considered ‘Vulnerable to 
Extinction’ globally (BirdLife International 2000) 
and ‘Endangered’ in Ecuador (Hilgert 2002). We 
provide the first detailed report of the basic 
biology, including nest site selection, nesting 
biology, and habitat use of the Brown Wood Rail. 
METHODS 
Field work was conducted at Bilsa Biological 
Station (79° 45' W, 0° 22' N, 330-730 m eleva¬ 
tion), a 3,500-ha private reserve operated by 
Fundacion Jatun Sacha within the 70,000-ha 
Mache-Chindul Ecological Reserve in Esmeraldas 
Province, Ecuador. Bilsa is approximately two- 
thirds undisturbed humid rain forest and one-third 
secondary forests (extensively logged with 10- 
20 years of regeneration) or selectively-logged 
forests (high-graded 10-20 years ago). The 
surrounding area contains patches of primary, 
selectively logged, and secondary forests inter¬ 
spersed among areas used for cacao (Theobroma 
cacao ) cultivation, grazing livestock, and other 
agricultural uses. 
We conducted systematic surveys for Brown 
Wood Rail nests throughout Bilsa from January 
?007 to January 2009. We monitored activity at 
nests from blinds using 10X binoculars to record 
status and behaviors, and recorded nest location 
and elevation using hand-held global positioning 
system (GPS) units. We quantified habitat char¬ 
acteristics around all but one nest by measuring 
canopy height, canopy openness (with a spherical 
densiometer), and number of trees with diameter 
at breast height (DBH) between 10 and 50 cm in 
137 
