THE CONDOR
Vol. 105, Number 1
February 2003 C.E.
TABLE OF CONTENTS

FEATURE ARTICLES
Low Genetic Variability in the Geographically Widespread Andean Condor 1
SHER L. HENDRICKSON, ROBERT BLEIWEISS, JUAN CARLOS MATHEUS, LILLY SILVA DE MATHEUS, NORBERTO LUIS JÁCOME AND EDUARDO PAVEZ
Seasonal, Age, and Sex Differences in Weight, Fat Reserves, and Plasma Corticosterone in Western Sandpipers 13
KATHLEEN M. O'REILLY AND JOHN C. WINGFIELD
Boreal Forest Songbird Communities of the Liard Valley, Northwest Territories, Canada 27
CRAIG S. MACHTANS AND PAUL B. LATOUR
Are Barred Owls Displacing Spotted Owls? 45
ELIZABETH G. KELLY, ERIC D. FORSMAN AND ROBERT G. ANTHONY
Annual Survival and Recruitment in a Ruby-throated Hummingbird Population, Excluding the Effect of Transient Individuals 54
BILL HILTON JR. AND MARK W. MILLER
Breeding Success of a Specialist Brood Parasite, the Screaming Cowbird, Parasitizing an Alternative Host 63
MYRIAM E. MERMOZ AND GUSTAVO J. FERNÁNDEZ
Prior Breeding Success Affects Return Rates of Territorial Male Ovenbirds 73
PAUL A. PORNELUZI
Red-necked Grebes Become Semicolonial When Prime Nesting Substrate is Available 80
GARY L. NUECHTERLEIN, DEBORAH BUITRON, JOEL L. SACHS AND COLIN R. HUGHES
Spatial and Temporal Variation of Diet within a Presumed Metapopulation of Adélie Penguins 95
DAVID G. AINLEY, GRANT BALLARD, KERRY J. BARTON, BRIAN J. KARL, GREG H. RAU, CHRISTINE A. RIBIC AND PETER R. WILSON
Feeding Behavior of Cooper's Hawks at Urban and Rural Nests in Southeastern Arizona 107
WENDY A. ESTES AND R. WILLIAM MANNAN
Winter Shorebird Communities and Tidal Flat Characteristics at Humboldt Bay, California 117
TAMAR DANUFSKY AND MARK A. COLWELL


SHORT COMMUNICATIONS
Giving-up Densities and Habitat Preferences of European Starlings and American Robins 130
JOSEPH O. OYUGI AND JOEL S. BROWN
The Relative Importance of Arthropods and Fruits in Foraging Behavior of Omnivorous Tanagers (Thraupidae): The Comparison of Three Methods 135
KAZUYA NAOKI
Comparative Analysis of the Rattle Calls in Corvus and Nucifraga: The Effect of Body Size, Bill Size, and Phylogeny 139
PAOLA LAIOLO AND ANTONIO ROLANDO
Can Surveillance Radar Be Used to Monitor the Foraging Distribution of Colonially Breeding Alcids? 145
KRISTJAN LILLIENDAHL, JON SOLMUNDSSON, GUDMUNDUR A. GUDMUNDSSON AND LORNA TAYLOR
New Records of Storks (Ciconiidae) From Quaternary Asphalt Deposits in Cuba 150
WILLIAM SUÁREZ AND STORRS L. OLSON
Male Chestnut-collared Longspurs are Essential for Nestling Survival: A Removal Study 154
SHARON E. LYNN AND JOHN C. WINGFIELD
Orientation and Microclimate of Horned Lark Nests: The Importance of Shade 158
C. ALEX HARTMAN AND LEWIS W. ORING


BOOK REVIEWS
Avian Incubation: Behaviour, Environment, and Evolution, edited by D. C. Deeming 164
KEITH W. SOCKMAN
Briefly Noted: Asian Buffet&emdash;All You Can Read 166
WILLIAM I. BOARMAN
Extinct Birds, Second Edition, by Erroll Fuller 167
ROBERT C. FLEISCHER
NEWS AND NOTES 170

AWARD ANNOUNCEMENTS
174

INFORMATION FOR CONTRIBUTORS
176