148 
THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 1, March 2011 
TABLE 1. Habitat characteristics at nest sites in > 14 independent home ranges of Snowy-cheeked Laughingthrushes at 
Lianhuashan, Gansu, China, during 2003-2008 in comparison with available sites. 
Habitat components 
Nest sites ( n 
Mean 
— 31) 
SE 
Available sites (n 
Mean 
= 38) 
SE 
t 
p 
Canopy cover (%) 
72 
4 
55 
3 
3.15 
000 
Spruce-fir density (trees/ha) 
455 
68 
674 
66 
-2 28 
003 
Birch density (trees/ha) 
206 
52 
329 
59 
-1 52 
013 
Shrub density (shrubs/ha) 
1,035 
95 
618 
156 
2 17 
003 
Shrub cover (%) 
66 
6 
32 
4 
4.27 
0.00 
during which each egg lost -0.07 g (1.2%) of its 
mass per day on average. Hatchlings, weighing 
4.7 ± 0.1 g (4.60-4.75 g; n = 3), were largely 
naked with dull grayish-red skin and only a few 
gray-white down feathers on the capital, occipital, 
middle spinal, and femoral tracts. Nestlings 
opened their eyes at 7 days of age and fledged 
at 16-18 days of age (n = 3 nests). Mean nestling 
mass was 38.9 ± 0.7 g (n = 5) at 15-18 days 
post-hatching, about 54% of the adult mass (67.8- 
74.0 g, n = 4). Growth rate (logistic regression 
model) was estimated to be 0.80 ± 0.01 g/day for 
three nestlings in one nest. 
Nest L° cc >tion and Description. —'Thirty-one 
nests were in coniferous-deciduous forests ( 74 %) 
or coniferous forests (26%); they were 13 ± 3 m 
2 sn^om 0 " 1 ^ f ° reSt Cdge - at elevations of 
2,800-^.900 m. Laughingthrushes favored north- 
east-facing slopes (30% of nests) with the mean 
steepness of 27 ± 1 ° (5-40°). Nest sites had lower 
pi uce-fir density, higher shrub density, and c-reater 
canopy cover and shrub cover than available sites 
(Table 1), suggesting the birds preferred nest sites 
with fewer conifers and denser shrubs. 
W ® re . P Iaced spruce (74.2%), fi r 
c), or deciduous shrubs (honeysuckle [Loni- 
7ZTV = 12 ' 9% ' wilIow s = 3.2%, vines = 
f /0) - ; Spruce was used more often than expected 
rom observed availability at nest sites (y* = 
in thr’efrv 2 ' V ° ° 0) ' NeStS Were constr ucted 
m three types of positions: 2.0 ± 0.1 m n 3 _ 
= 34 * ° Ut from the trunk in larger conifers (DBH 
f<rnr " = l3g or touching the trunk 
( 0.3 m) in smaller conifers (DBH = 9 ± j cnr 
I1 , ) ' or atta ched to the branches and stems 
of shrubs (DBH = 4 ± 1 cm; „ = 7 ) Height 
ot nests in larger conifers were greater than in 
smaller conifers and in shrubs (1.9-3 5 vs 15 3 a 
vs. 1-1-2.6 m; F 2 , 30 = 4 . 2 , P = 0 03) iifh ,n 
average of 2.4 ± 0.1 m (n = 31 ) above ground 
he average surrounding and above cover at nests 
WCIC J ! 
(30-100%, n = 31), respectively. 
Twenty bowl-shaped nests had a mean inside 
diameter of 9.7 ± 0.2 cm (8.0-12.3 cm), an 
outside cup diameter of 16.4 ± 0.5 cm (13.5- 
22.0 cm), an inside depth of 3.6 ± 0.2 cm (2.0- 
5.0 cm), and an outside height of 7.8 ± 0.5 cm 
(5.5-15.5 cm). The inner bowl was lined with 
leaves of Carex spp. and thin strands from the 
stems of honeysuckle, raspberry (Rubuspungent), 
Sorbana kirilowii , Philadelphus incanus , and 
Spiraea spp. The outer bowl was made mostly 
of twigs, mainly mountain ash ( Sorbus spp.), 
honeysuckle, Rhamnus parvifolia and Cerasus 
clarofolia , and a few birches. Nest weight 
averaged 62 ± 7 g (35-130, n = 13). 
Nest Productivity and Success .—The mean 
clutch size was 3.5 ± 0.2 eggs (n = 21) with 2-. 
3-, 4-, and 5-egg clutches accounting, respectively, 
for 3, 5, 12, and 1 nests. Eggs averaged 27.1 ± 
0.2 mm (24.6-30.5 mm) in length and 19.8 - 
0.1 mm (18.4—21.1 mm) in width (n = 54 eggs in 15 
nests). The mass of eggs measured prior to 
incubation was 5.42 ± 0.13 g (4.90-405 g, n = 8). 
Overall breeding success was 60% for 20 known- 
fate nests with 2.7 ± 0.2 (2-4) hatchlings (n = 15) 
and 2.2 ± 0.2 (1-3) fledglings per clutch (n = 12). 
Six nests failed due to predation (3 each during the 
incubation and nestling periods). Nestlings in two 
nests died after a week of rain (15-22 Jun 2007). 
during which the air temperature averaged only 
5.0 C (—0.1—11° C). One to two unhatched eggs 
disappeared in 5 of 9 nests and 25-50% (1 ot 2) 
nestlings disappeared in 5 of 12 nests during the 
nestling period. No eggs disappeared in 15 nests 
during the incubation period. 
Parental Duties .—Both males and females 
participated in building nests, incubating egg s ’ 
and provisioning and brooding nestlings. Pairs 
defended nests by calling vociferously when we 
checked the eggs or nestlings. Scattered observa- 
