Karubian et al. • BIOLOGY OF BROWN WOOD RAILS 
139 
(B) 
FIG. 1. Brown Wood Rail in Bilsa Biological Station, northwest Ecuador. (A) Interior of a nest with the average clutch 
size of four eggs. (B) Two recently-hatched chicks with two eggs about to hatch. (C) A nest 1 .6 m agl on top o a ree s up 
with vegetation temporarily pulled back for purposes of the photograph. (D) Adult. (Photograp s y 
photograph D by L. Carrasco). 
trees with DBH between 10 and 50 cm, and 0.44 
' 0.9 trees with DBH > 50 cm. Eleven nests 
were in secondary forest, four in selectively- 
l°gged forest, and one in primary forest. Com¬ 
parison of nest site to habitat availability in the 
Bilsa area (based on 87 sampled points) revealed 
Brown Wood Rails used secondary forests as 
nesting sites in a larger proportion than this 
habitat is available in the area we sampled (x 2 2 = 
13 -74, P = 0.001). 
Morphological measurements for three individ- 
L 'als of unknown gender were: mass (506.7 ± 
61-1 g), tarsus ( 73.9 ± 1.0 mm), wing chord 
'175.8 ± 1.8 mm), tail length (52.4 ±1.7 mm), 
beak depth (16.5 ± 3.3 mm), beak width (8.9 ± 
H 9 mm), culmen from the distal edge of the nare 
*79.4 ± 1.8 mm), and exposed culmen (55.6 ± 
9 1 mm). The eye ring and the iris were intensely 
bright red in all individuals (Fig. ID). 
We conducted 24 radio-tracking sessions and 
°btained 150 independent locations of a radio- 
marked bird of unknown gender between 12 March 
and 9 October 2008. This individual used a clearly 
defined territory whose overall MCP home range 
Slze was 13.5 ha; 95 and 50% kernel home range 
sizes were 9.0 and 0.9 ha, respectively. The radio- 
equipped individual was active throughout the day 
and at night was observed roosting 5 m above the 
forest floor in a ~7-m tall Melastomataceae tree, 
suggesting a diurnal pattern of activity. We 
opportunistically observed adults eating tadpoles 
from small puddles (10 cm 2 ) in muddy trails and 
small streams on five separate occasions. 
The radio-marked bird was seen and/or heard 
with at least one other adult throughout the radio¬ 
tracking period. We recorded three distinct types 
of vocalizations: ( 1 ) a sharp, crackling vocaliza¬ 
tion audible at short distances used when nesting, 
heard when adults replace each other incubating 
or when adults called recently-hatched young; ( 2 ) 
a low frequency call audible for long distances 
used by adults of the same pair, perhaps to 
establish territoriality; and (3) a loud crackling 
call also audible over long distances which 
corresponds to the “kyow” of Ridgely and 
Greenfield (2001). 
DISCUSSION 
This is the first published account of the nesting 
biology and home range for any member of the 
