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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 1, March 2011 
(1994). The nestling and adult gradually returned to 
the relaxed position, if left undisturbed for ~ 10 min. 
During relaxed situations, and when the 
nestling was on its own in the nest, it frequently 
engaged in feeding on passing flies and in 
maintaining its plumage. We did not perceive if 
the nestling captured prey during the faster 
feeding bouts, but this foraging behavior may be 
important in the early stages of species maturation 
as it optimizes food intake by the nestling in 
periods of absence of adults. Preening is also 
important to get rid of mites and lice (Cohn-Haft 
1999). Adults performed the same behaviors when 
they were sitting in the nest. Feeding bouts of 
adults while perched are a way to supplement 
their diet without flying and abandoning its 
primary defense of inconspicuousness. 
Defecation was another observed care behavior 
2005, Greeney et al. 2008, Corbo and Macarrao 
2010), possibly facilitated a predation event. 
However, several behaviors of the species led to 
the inconspicuousness during this time, and the 
long time of parental investment attest to their 
protective value for survival (Skutch 1970, Cohn- 
Haft 1999). New methods and technology to 
precisely study behaviors are needed. The use of 
infrared cameras in future studies would allow 
obtaining better insight of the nightly activities at 
the nest. Identification of the gender of adults 
would allow better study of how males and females 
share incubation and brooding duties. 
ACKNOWLEDGMENTS 
We are grateful to two anonymous reviewers for their 
appropriate suggestions about this manuscript. 
of the nestling. This occurred when the nestling 
raised its tail and ejected feces 30 to 50 cm from 
the nest. The absence of feces in and near 
Common Potoo nests has been reported (Skutch 
1970, Sick 1993, Cohn-Haft 1999, and Lopes and 
Anjos 2005). This behavior should reduce the risk 
of predation and presence of parasites. 
The nestling uttered a soft song while alone and 
on occasions that it was accompanied by one of 
the adults. This behavior has been reported in the 
literature prior to the arrival of an adult at the nest 
(Skutch 1970, Corbo and Macarrao 2010). 
Stronger calls in our study were also uttered by 
an adult when it approached the nest, probably to 
inform the nestling of its presence. The nestling 
increased the frequency of begging for food calls 
when an adult arrived at the nest, and when the 
adult fed it by regurgitation. Adults came to the 
nest three to 10 times to feed the nestling by 
regurgitation before midnight, similar to the 
observations of Skutch (1970) and Lopes and 
Anjos (2005). One of the parents (adult B) came 
more frequently to the nest, but we were not able 
to identify if it was male or female. 
Cryptic plumage, inconspicuous behavior, and 
reduced activities around the nest are all adapta¬ 
tions to reduce attention to nesting potoos (Cohn- 
Haft 1999). The 51 days of the nestling period of 
the Common Potoo from hatching to young 
departure from the nest (Skutch 1970) is consid¬ 
ered very long among birds (Sick 1993). The lower 
leight of the nest in our study, in comparison with 
the interval from 3 to 15 m reported in other studies 
( un and Butler 1925, Haverschmidt 1958 
Borrero 1970, Skutch 1970, Lopes and Anjos 
LITERATURE CITED 
Borrero, H. J. I. 1970. Photographic study of the Potoo in 
Colombia. Living Bird 9: 257-263. 
Cleere, N. 1998. Nightjars. A guide to the nightjars, 
nighthawks, and their relatives. Yale University Press. 
New Haven, Connecticut, USA. 
Cohn-Haft, M. 1999. Family Nyctibiidae (Potoos). Pages 
288-300 in Handbook of the birds of the world. 
Volume 5. (Barn-owls to hummingbirds) (J. delHoyo, 
A. Elliott, and J. Sargatal, Editors). Lynx Editions. 
Barcelona. Spain. 
Corbo, M. C. and A. Macarrao. 2010. Parental care in 
Common Potoo Nyctibius griseus in Brazil. Cotinga 
32: 122. 
Goeldi, E. A. 1896. On the nesting of Nyctibius 
jamaicensis and Sclerurus umbretta. Ibis 7: 229-310. 
Greeney, H. F., J. Simbana, and A. P. Tangila. 2008. 
Threat display and hatchling of Common Potoo 
Nyctibius griseus. Cotinga 29: 172-173. 
Haverschmidt, F. 1958. Notes on Nyctibius griseus in 
Surinam. Ardea 46: 144-148. 
Holyoak, D. 2001. Nightjars and their allies. The 
Caprimulgiformes. Oxford University Press, Oxford. 
United Kingdom. 
Lopes, E. V. and L. Anjos. 2005. Observances sobre 
reprodunao de Nyctibius griseus no campus da 
Universidade Estadual de Londrina, norte do Parana. 
Ararajuba 13: 109-112. 
Muir, A. and A. L. Butler. 1925. The nesting of Nyctibius 
griseus (Gmel.) in Trinidad with photographs. Ibis 32: 
654-659. 
Sick, H. 1993. Birds in Brazil. A natural history. Princeton 
University Press, Princeton, New Jersey, USA. 
Skutch, A. F. 1970. Life history of the Common Potoo. 
Living Bird 9: 265-280. 
Tate, D. P. 1994. Observations of nesting behavior of the 
Common Potoo in Venezuela. Journal of Field 
Ornithology 65: 447-452. 
