738 
THE WILSON JOURNAL OF ORNITHOLOGY . Vol. 
124. No. 4. December 2012 
LEGEND 
Pine plantations 
Native forest 
Nest-box plot 
Nothofagus forest (black) arc embedded inT matrix°of exotic^M "i SOUth< : enlral Chile ' Fragmented remnants of nativ 
* ° f eXO,lc Mon,erre y P ine (Pinus radiata) plantations (gray). 
area was ortginally a deciduous forest of No,ho- 
fagus glauca (Hualo), which began being exploit- 
n 10 th f l9,h cenlu ry (San Martin and 
r: ? ^ MaUle «ow contains 
e of the largest concentrations of />, radiata 
P antauons in the country, covering 76% of the 
Coasta Range. Native forest remains in small 
rev n, tragmenlS surroun ^d by exotic Monter¬ 
ey p,ne P lamat,ons - The climate is warm 
temperate with an oceanic influence. The average 
m nimtim temperature is 5.9 C during winter 
(Jul) and the mean maximum temperature is 2^ 7 
u during summer (Jan). Mean annual rainfall is 
881 mm (Estades and Temple 1999 ) 
We worked in plantations that were 18 years of age 
«£ »n"S Pl ^»r,® l Samp,e 
2009 ) n J r r ° m l,e nest (van Dongen et al 
between 2°5 tnd^m lrec «™nta 
three boxes in sin ! hc grOUnd *"> all 
, e>" 1 sin. wium ot i o cm, and 
entrance hole of 3 cm in diameter (Moreno et 
2005, 2007). 
Nt ; st Monitoring .-We checked nest box 
wee ly fiom the last week of August, recordir 
any sign of nesting activity, including use of twit 
and/or feathers to build die nest. We increase 
frequency of monitoring once we observe 
activity in the box to detect laying dates (date c 
lust egg) and hatching dates (date of fir; 
hatchling in the nest). The latter frequenc 
depended on advancement of the nest buildin: 
stage, from three times per week to daily when th. 
nest was nearly completed. We weighed ant 
measured eggs on the day they were laid. Lengtl 
and width were measured to the nearest 0.1 mn 
WM 1 a , r ‘§ l,a l caliper. Egg volume was obtained 
using Hoyt's (1979) formula: Volume = 0.51 
(Length X Width?). 
We captured adults with traps in the nest box 
w en nestlings were 13 days of age and banded 
mem with a combination of three plastic colored 
an s under the authority of Servicio Agricola y 
'unadero ot Chile. Adult mass was recorded with 
‘ spnng balance to the nearest 0.1 g. We measured 
w:; h JS '! m . lea< J~t»ill length to the nearest 0.1 mm 
a ca (iper. and wing length and the two 
