284 
THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 2, June 2011 
TABLE 1. Longitude/latitude and brood size of Varied 
Tits at three sites, Mt. Jiri, Korea, 2007. 
Brood size 
Area 
Longirude/laiiiude (mean ± SE (n)) 
Piagol (300 m) 
N 35° 15' 37.1" 6.69 ± 0.75 (17) 
E 127' 35' 00.1" 
Siamjae (900 m) 
N 35" 18' 14.6" 6.26 ±1.15 (7) 
E 127° 20' 46.6" 
Nogodan (1,400 m) 
N 35° 17' 36.9" 5.90 ± 0.70 (II) 
E 127° 31' 42.4" 
under increased provisioning pressure caused by 
elevation and growth of nestlings. 
METHODS 
We selected three areas (Piagol at 300 m, 
Siamjae at 900 m, and Nogodan at 1,400 m) with 
similar vegetation but at different altitudes along 
Mt. Jiri at the southern extremity of Korea and 
established 48 nest boxes at each site in 
November 2006. This research was conducted 
during the breeding season (Apr-Jun) of Varied 
Tits in 2007. Parents were captured at their nest 
boxes while incubating. A small amount of blood 
was collected from each bird to ascertain gender 
genetically using an amplification refractory 
mutation system method (Ito et al. 2003), and a 
colored band was placed on legs of females to 
distinguish them from males. Video cameras 
(Sony Handycam HDR-SR1) were positioned in 
front of nest boxes in which the gender of parents 
was known, and visits (per hour) of female and 
male Varied Tits were recorded. We acquired data 
from 17 nests at Piagol, 7 nests at Siamjae. and 11 
nests at Nogodan; the recording time for each nest 
was 4-8 hrs per day. The total recording time was 
1,204, 571, and 976 hrs for the three areas, 
respectively. The provisioning rate of males or 
females was calculated as the number of times the 
parent visited the nest per hour divided by the 
number of nestlings in the nest. We used repeated 
measure analysis of variance (ANOVA) to test 
effects of nestling age on effects of gender of 
parents and sites. 
RESULTS 
Brood size decreased with altitude (Tabic 1) 
The provisioning rate of female Varied Tits was 
higher than for males in all three areas (Fig. I. 
Table 2). Provisioning rates increased with 
altitude based on significant differences among 
the three areas (Fig. 2, Table 3). The provision¬ 
ing rate of parents based on nestling age was low 
during the first few days after hatching, but 
gradually increased and reached a peak when 
nestlings were 10 days of age (Pearson Correla¬ 
tion ~ 0.673, P < 0.0001). Provisioning rates of 
females during the peak provisioning period (8- 
10 days) were not significantly different from 
those at other times of the nestling peritx) at any 
of the three sites (Table 3). However, provision¬ 
ing rates of males during this period were 
different from those at any other time (/-test. 
P < 0.0001). The provisioning rate of female 
Varied Tils increased with elevation (Table 3). 
because variation in provisioning rates across the 
altitudinal gradient was higher for males than for 
females (repeated measure ANOVA, Sites*gen- 
der, P — 0.001). The increment ratio of females 
at altitude was lower than that of males. The 
relative ratio of male provisioning rate to female 
provisioning rate increased at Siamjae (900 m) 
and Nogodan (1,400 m) until 9-10 days after 
5 1 
if! 
Nestling Age (days) 
NoglS’J (l,4S V m) 0nm8 ratCS ° f malC 3nd fCmale Var ' ed T ' tS 3t (A) Piago1 (30 ° m) ’ (B) siam J ae ( 90 ° m) ’ and ( ° 
