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THE WILSON JOURNAL OF ORNITHOLOGY • Vol. 123, No. 1, March 2011 
Common Buzzard is in Europe (Thiolley 1994). 
Mixed broods of Red-tailed Hawks and Bald 
Eagles in the USA occurred at a frequency of 
0.5% (3 of 662) of eagle broods observed during 
1987-1991 (Watson et al. 1993). Our data are 
presently too limited to calculate a frequency of 
adoptions of Common Buzzards in White-tailed 
Sea Eagle nests in Europe. 
ACKNOWLEDGMENTS 
This study was funded by Grant Number MSM6215712402 
of the Ministry of Education, Youth and Sports of the Czech 
Republic. 
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The Wilson Journal of Ornithology 123(1): 176—178, 2011 
Cruise Ships as a Source of Avian Mortality During Fall Migration 
Carol I. Bocetti 1 ’ 2 
ABSTRACT.—Avian mortality during fall migrati 
has been studied at many anthropogenic structures, mi 
of which share the common feature of bright lightii 
An additional, unstudied source of avian mortal 
during fall migration is recreational cruise ships that £ 
brightly lit throughout the night. I documented a sins 
mortality event of eight Common Yellowthroi 
(Geothlypis triehas) on one ship during part of o 
1 USGS, Patuxent Wildlife Research Center, 250 Uni¬ 
versity Avenue, Box 45, California, PA 15419, USA. 
Current address: California University of Pennsylvania 
250 University Avenue, Box 45, California, PA 15419 ' 
USA; e-mail: bocetti@calu.edu 
night in fall 2003, but suggest this is a more wide-spread 
phenomenon. The advertised number of ship-nights for 
50 cruise ships in the Caribbean Sea during fall 
migration in 2003 was 2,981. This may pose a 
significant, additional, anthropogenic source of mortal¬ 
ity that warrants further investigation, particularly 
because impacts could be minimized if this source of 
avian mortality is recognized. Received 21 October 
2009. Accepted 23 August 2010. 
Mortality during migration of neotropical 
migratory songbirds is an important topic to bird 
conservationists. Anthropogenic causes of mor- 
