380 THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 124. No. 2. June 2012 
The Wilson Journal of Ornithology 124(2):380-384. 2012 
First Nesting Information for the Orange-eared Tanager 
(Chloroch rysa cci /1 ipa re a) 
Manuel A. Sanchez Martinez 1,4 and Gustavo A. Londofio 2,3 
ABSTRACT.—The Orange-eared Tanager ( Chloro - 
chrysa caUiparea) occurs from southern Colombia to 
northern Bolivia between 900 and 2,000 m elevation. 
We describe for the first time the nest of the genus 
Chlorochrysa, based on live nests of C. caUiparea, and 
provide information on incubation and nestling growth 
from August through December 2009 and 2010 in IVtanu 
National Park, Cusco, Peru, the Orange-cared Tanager 
has a distinct and unique nest location in clumps of 
moss hanging from horizontal branches, previously 
unknown among tanagers. The nest structure, however, 
was similar to that ol most tanagers. We observed use 
of a nest-like structure as a dormitory, not previously 
reported lor the Thraupidae. Clutch si/e was one egg 
and the nestling period was 21 days. The female made 
an average ol 8,8 foraging trips/day from the nest which 
lasted on average 33.1 min with nest attentiveness of 
58.9%. The small clutch suggests close affinity with 
mountain tanagers. Received 24 February 2011. Ac¬ 
cepted 31 October 2011. 
The tanager genus Chlorochrysa (Thraupidae) 
is considered to be sister to the clade comprising 
Stephanophorus, Diuca, Neothraupis. Lophospin- 
gus, Cissopis, Schistoclamys, and Paroaria. The 
Chlorochrysa and Stephanophorus—Paroaria 
clade is in turn sister to the group of colorful 
mountain tanagers (Sedano and Bums 2010). 
There are three species in the genus Chlorochrysa 
(C. calliparaea, C. nitidissima, and C. phoenico- 
tis) with exclusively South American distributions 
in the Andean foothills from Venezuela to Bolivia 
with an elevational distribution from 1,000 to 
1,800 m in low/wel outlying ridges within the 
Andes region, where mossy cloud forest is 
generally found. The genus is characterized by 
their long and slender bills, strong tarsi, and a 
small patch of distinctive club-shape feathers on 
' Departamcnto de Biologfa, Universidad del Valle, A.A. 
25360, Cali-Colombia. 
-Florida Museum of Natural History. Dickinson Hall. Univer¬ 
sity of Florida, Gainesville, FL 32611. USA. 
3 Department of Biology, 227 Bartram Hall. University of 
dorida. P. O. Box 1 18525. Gainesville, FL 32611, USA 
Corresponding author: 
e-mail: manusama79@gmail.com 
the ear-coverts (Hilty and Brown 1986, Isler and 
Isler 1999. Ridgely and Tudor 2009). 
flic breeding biology of the Orange-cared 
Tanager (Chlorochrysa caUiparea ) is almost 
unknown. There is only one brief description of 
a cup nest of the Glistening-green Tanager (C. 
phoenicotis) hollowed in moss on the side of a 
limb in the middle strata (Hilty and Brown 19861, 
We describe for the first time the nest for the 
genus Chlorochrysa based on five nesls of C. 
caUiparea. and detailed information on incubation 
and nestling growth. 
METHODS 
Study Area .—This study occurred at the Cock- 
of-the-Rock Lodge (13 03' 19.4" S, 71' 32' 48.5" 
W) managed by the Peruvian non-governmenlal 
organization (NGO) Peru Verde. It is in the buffer 
area of Munu National Park. Cusco. Peru, on the 
eastern slope of the Andes at the confluence of the 
Sun Pedro and Kcosnipata rivers. The Reserve 
covers an elevation gradient from 1.000 to 2,000 m. 
and protects a cloud forest with abundant mosses 
and epiphytes, a canopy height of 25 m, and 
average temperature of 16.15 C (min-max = 
13.6 to 19.8 C) with a rainy season between 
November and April and a dry season from May 
to August. 
Nest, Egg. Incubation, and Nestling Measure¬ 
ments .—Daily nest searches were conducted by 
six researchers each year betw'een August and 
December 2009 and 2010 (10 hrs/day, 6 days/ 
week). Each researcher had a unique plot of 10- 
15 ha throughout the field season. We found five 
active nests of C. caUiparea. Most nests had an 
egg or a nestling, but one was found during die 
building stage. W'e measured length and width ol 
eggs when found with a caliper to the nearest 
0.1 mm and mass with a digital pocket scale 
(FlipScale F2, Phoenix. AZ. USA) to the nearest 
0.05 g. We placed two small thermal sensors (2 
I mm), one inside the nest under the egg and the 
other next to the external surface of the nest wall 
The thermal sensors were attached to a U12 four- 
