Contents
A New Tody-tyrant from Northern Peru
John W. Fitzpatrick and John P. O'Neill
Nectar Loss by Golden-winged Sunbirds to Competitors
Frank B. Gill and Larry L. Wolf
Geographical Variation in Songs of California House Finches (carpodacus Mexicanus)
Erik Bitterbaum and Luis F. Baptista
Notes on the Puna Avifauna of Az
Nicholas A. Roe and William E. Rees
Notes and News
The Auk
Evaluation of a Method for Estimating the Laying Rate of Brown-headed Cowbirds
D. M. Scott and C. Davison Ankney
An Assessment of Male Parental Investment and Pair Bonding in the Polygamous Superb Lyrebird
Alan Lill
Seasonal Variation in Avian Community Structure: Differences in Mechanisms Regulating Diversity
J. T. Rotenberry, R. E. Fitzner, and W. H. Rickard
Vocal Dueling among Male Marsh Wrens: Evidence for Ritualized Expressions of Dominance/subordinance
Donald E. Kroodsma
Sexual Segregation of Red-billed Queleas (quelea Quelea) in the Awash River Basin of Ethiopia
M. M. Jaeger, W. A. Erickson, and M. E. Jaeger
Allopreening in Owls: what Are Its Functions?
Eric D. Forsman and Howard M. Wight
Seasonal, Annual, and Geographic Variation in Sex Ratio of Wintering Populations of Dark-eyed Juncos (junco Hyemalis)
Ellen D. Ketterson and Val Nolan Jr.
An Analysis of Breeding and Mortality in a Maturing Kittiwake Colony
Robert J. Kosinski and Richard H. Podolsky
Blue-phase Ross' Geese and Other Blue-phase Geese in Western North America
M. Robert Mclandress and Ilse Mclandress
Territory Size in Wintering Sanderlings: the Effects of Prey Abundance and Intruder Density
J. P. Myers, P. G. Connors, and F. A. Pitelka
Annual Productivity and Its Measurement in a Multi-brooded Passerine, the Eastern Bluebird
Benedict C. Pinkowski
Reproductive Separation and Isolating Mechanisms Between Sympatric Dark- and Light-phase Western Grebes
John T. Ratti
Courtship and the Pair-bond of Pileated Woodpeckers
Lawrence Kilham
Two Apparent Hybrid Zonotrichia Sparrows
Robert B. Payne
Extralimital Nesting of Bay-breasted Warblers: Response to Forest Tent Caterpillars?
Spencer G. Sealy
Belly-soaking as a Thermoregulatory Mechanism in Nesting Killdeers
Bette J. Schardien and Jerome A. Jackson
Cleaning/feeding Symbiosis Between Grackles (quiscalus: Icteridae) and Map Turtles (graptemys: Emydidae)
Richard C. Vogt
Notes on the Masked Saltator, Saltator Cinctus, in Peru
John P. O'Neill and Thomas S. Schulenberg
Is Displacement a Sign of Female Dominance or Only a Response to Close Following by Males Trying to Avoid Being Cuckolded?
Harry W. Power
Status of the American Flamingo in the Dominican Republic and Eastern Haiti
James W. Wiley and Beth Nethery Wiley
The Diet of the Barn Owl in Central Chile and Its Relation to the Availability of Prey
Fabian M. Jaksic
Short-term Change in Vegetation Structure and Its Effect on Grasshopper Sparrows in West Virginia
Robert C. Whitmore
The Incubation Temperature of Leach's Storm-petrel
Robert E. Ricklefs and Hermann Rahn
Weather-dependent Foraging of Great Blue Herons (ardea Herodias)
R. Russell Bovino and Edward H. Burtt Jr.
Parental Behavior of a Replacement Male Dark-eyed Junco
Thomas A. Allan
Covers
Front Matter
The Auk
Back Matter
The Auk