ARTICLES

Population estimates of Nearctic shorebirds. R. I. G. Morrison, R. E. Gill, Jr., B. A. Harrington, S. Skagen,
G. W. Page, C. L. Gratto-Trevor, and S. M. Haig ................................................................................................. 337-352

Foraging behavior and habitat choice of wintering Northern Shoveler in a major wintering quarter in
France. M. Guillemain, H. Fritz, and N. Guillon .................................................................................................. 353-363

Temporal variability in abundance of Marbled Murrelets at sea in southeast Alaska. S. G. Speckman,
A. M. Springer, J. F. Piatt, and D. L. Thomas ....................................................................................................... 364-377

Comparative productivity of American Black Ducks and Mallards nesting in agricultural landscapes of
southern Québec. C. Maisonneuve, R. Mc Nicoll, and A. Desrosiers .................................................................. 378-387

Trends in Caspian Tern numbers and distribution in North America: a review. L. R. Wires and F. J.
Cuthbert ................................................................................................................................................................. 388-404

Sexing adult Black-legged Kittiwakes by DNA, behavior, and morphology. P. G. R. Jodice, R. B. Lanctot,
V. A. Gill, D. D. Roby, and S. A. Hatch .................................................................................................................. 405-415

Effects of ENSO and PDO events on seabird populations as revealed by Christmas Bird Counts.
R. Vandenbosch ...................................................................................................................................................... 416-422

Densities of Barrow's Goldeneyes during winter in Prince William Sound, Alaska in relation to habitat,
food, and history of oil contamination. D. Esler, T. D. Bowman, C. E. O'Clair, T. A. Dean, and L. L.
McDonald ............................................................................................................................................................... 423-429

Composition, spatial, and temporal variation of Common and Arctic Tern chick diets in the Gulf of Maine.
C. S. Hall, S. W. Kress, and C. R. Griffin ............................................................................................................... 430-439

Population research priorities for Black Terns developed from modeling analyses. F. A. Servello ................ 440-448

Effects of habitat modification on breeding seabirds: a case study in central Chile. A. Simeone and M.
Bernal ..................................................................................................................................................................... 449-456

Breeding biology of the Pigeon Guillemot in the Chukotka Peninsula, Russia. N. B. Konyukhov .................. 457-467

Low reproductive success of Black Skimmers associated with low food availability. C. A. Gordon, D. A.
Cristol, and R. A. Beck ........................................................................................................................................... 468-474

Population studies of Piping Plovers at Lake of the Woods, Minnesota: 19 year history of a declining
population. S. J. Maxson and K. V. Haws ............................................................................................................ 475-481

NOTES
When do Dunlins spend high tide in flight? H. Hötker ....................................................................................... 482-485

Absence of haematozoa and ectoparasites in a highly sexually ornamented species, the Crested Auklet.
H. Engström, R. Dufva, and G. Olsson .................................................................................................................. 486-488

Sexual size dimorphism in the Antarctic Shag. R. Casaux and A. Baroni .......................................................... 489-493

Breeding of Brown Boobies in the Gulf of California: seasonality and apparent effects of El Niño.
E. Mellink ............................................................................................................................................................... 494-499

Nest size and location in relation to reproductive success and breeding timing of tree-nesting Great
Cormorants. R. B. Childress and L. A. Bennun .................................................................................................... 500-505

Population size of Humboldt Penguins assessed by combined terrestrial and at-sea counts. G.
Luna-Jorquera, S. Garthe, F. G. Sepulveda, T. Weichler, and J. A. Vásquez ....................................................... 506-510

Inter-annual variation in the autumn diet of the Gentoo Penguin at Laurie Island, Antarctica. N. Coria,
M. Libertelli, R. Casaux, and C. Darrieu ............................................................................................................... 511-517

Predicting the sex of Kelp Gulls by external measurements. C. Torlaschi, P. Gandini, E. Frere, and
R. M. Peck .............................................................................................................................................................. 518-520

Notes on the habitat, behavior, and vocalizations of Zigzag Herons in Venezuela. D. Ascanio-Echeverria
and W. E. Davis, Jr. ............................................................................................................................................... 521-523

NOTEWORTHY LITERATURE: Edited by David N. Nettleship................................................................... 524-534

COMMENTARY
Integrating climate change and predation risk with wading bird conservation research in North America.
R. W. Butler and R. G. Vennesland ....................................................................................................................... 535-540

INDEX.................................................................................................................................................................. 541-548

ERRATA.............................................................................................................................................................. 549

EDITOR'S COMMENTS .................................................................................................................................. 550-551

2000 LIST OF REFEREES ................................................................................................................................ 551

EDITORIAL STAFF .......................................................................................................................................... 552