The Marin County breeding bird atlas : a distributional and natural history of coastal California birds

500 Pages·1993·37.8 MB·English

by  Shuford, W. David, 1949-

MARIN COUNTY
THE
BREEDING BIRD ATLAS
A
Distributional and Natural History of Coastal California Birds
W. DAVID SHUFORD
A
Project of
Point Reyes Bird Observatory
Bushtit Books
Digitized by the Internet Archive
2013
in
http://archive.org/details/marincountybreedOOshuf
THE MARIN COUNTY
BREEDING BIRD ATLAS
THE MARIN COUNTY
BREEDING BIRD ATLAS
A
Distributional and Natural History
of Coastal California Birds
W.
David Shuford
Illustrations by Keith Hansen and Ane Rovetta
Maps by Dewey Livingston
Photographs by Ian Tait
California Avifauna Series 1
Bushtit
Books
A
Project of Point Reyes Bird Observatory
i y / /
©
Copyright 1993 by Point Reyes Bird Observatory.
All rights reserved. No partofthis book may be reproduced
in any mannerwhatsoeverwithoutwritten permission from
rite publisherexceptbya reviewerwhowishes toquote brief
passages in a review written for inclusion in a magazine,
newspaper, oranyelectronic broadcastmedia.
Publisher'sCataloging-in-Publication Data
Shuford,W. David, 1949-
The Marin County breeding bird atlas: a distributional and
natural historyofcoastal California birds,
p. cm.
Includes bibliographic references and index(p. )
1. Birds—California—Marin County. 2. Bird populations-
California—MarinCounty—Geographical distribution.
3. MarinCounty(Calif.)—Natural history. I. Title.
QL684.C2.S58 1993 598.2'9794'62 92-81834
ISBN 0-9633050-O-X
LibraryofCongress CatalogCard Number: 92-81834.
Publishedby BUSHTIT BOOKS
P.O. Box 233
Bolinas, CA94924
Printed in theUnited StatesofAmerica byBraun-Brumfield, Inc.,AnnArbor, Michigan.
Designedand typesetbySusanGoldhaberMurray.
Coverdesign bySusan Claire Peaslee.
Printedwith soy-based inks on acid-free, recycled paper.
The Marin CountyBreedingBirdAdas is a projectof:
POINTREYESBIRDOBSERVATORY,4990ShorelineHighway,Stinson Beach,CA94970. Foundedin
1965, Point Reyes Bird Observatory is a nonprofit membership organization dedicated to conducting
ecologicalresearch,interpretingresearchresultstothepublic,andprovidingascientificbasisforconservation
ofwildlifeandtheirhabitats. Fundingissuppliedbyresearchgrants,contracts,andindividualcontributions.
Skilledvolunteerwork is the backboneofmanyPRBO projects, including die one upon which this book is
based. PRBOprovidescredible, fact-based informationandguidelinesforpolicyissuesandpublicandprivate
environmental stewardship. Our studies ofbirds, marine mammals, and theirhabitats often involve issues
ofnational and international significance, suchasoil spill impacts,wedandsconservation,wildlife/fisheries
conflicts, and population threats to neotropical migrants.
Suggested citations (whole bookorindividual species accounts):
Shuford, W. D. 1993. The Marin County Breeding Bird Atlas: A Distributional and Natural History of
Coastal California Birds. CaliforniaAvifauna Series 1. BushtitBooks, Bolinas, Calif.
Peake, H. 1993. Hooded Oriole. In W. D. Shuford. The Marin County Breeding Bird Atlas: A
Distributionaland Natural HistoryofCoastalCalifornia Birds, 405-408. CaliforniaAvifauna Series
1. BushtitBooks, Bolinas, Calif.
To the late David Gaines,
my first bird mentor and an inspirational teacher, naturalist, and conservationist,
To StuartJohnston,
a born naturalistwho knows the birds so well and who lives as wild and free
as any ofthem, or us,
To Bob Stewart,
who not only started the Marin adas project
but as a teacher has probably opened the eyes ofmore budding naturalists in
Marin County dian anyone else,
and, ofcourse,
To my Family.

Contents
Contents vii Northern Dune Scrub 24
Northern Coastal Scrub 24
List ofMarin Breeding Bird Atlas Contributors . . . xi Coyote Brush-Sword Fern Scrub 24
List ofMarin Breeding Bird Atlas Participants . . . . xii Coastal Sage-Coyote Brush Scrub 24
Chaparral 24
Acknowledgments xiii
Chamise Chaparral 25
Illustrations xiv Manzanita Chaparral 25
Preface xv Mixed Chaparral 25
Serpentine Chaparral 25
INTRODUCTION Coastal Salt Marsh 25
1
Coastal Riparian Forest 26
AHisPteorrsipceacltiBvaeckognrtohuendHiosftoBrryeeodfiAnvgiaBnirDdiAstdraisbeustion. . 1 Freshwater Marsh 26
Bulrush-Cattail Marsh 26
Studies in California 2
Coastal Swale 27
History ofBreeding Bird Studies in Marin County,
Exotic Plants 27
California 3
Additional Breeding Bird Habitats 28
Origin ofthe Marin County Breeding Bird Adas
Project 6
HISTORY OF LAND USE
UNDERSTANDING BIRD DISTRIBUTION IN MARIN COUNTY 31
7
Marin CountyTopography 7
TIMING OF BREEDING
Geology and Soils 10 37
Climate 11
METHODS EMPLOYED IN THE
Seasonality 11
MARIN ATLAS
Temperatures 11 41
Precipitation 11 Grid System 41
Pacific Ocean Air and Current Cycles 12 Participant Instruction and Block Assignments . . 42
Climatic Extremes 16 GatheringAdditional Information 45
Coastal Summer Fog 16 DeterminingAdequacy ofCoverage 46
OtherAdases 46
MARIN COUNTY
The Marin Adas 47
BREEDING BIRD HABITATS 19 Data Summary 48
Marin County Plant Communities 19 Quantitative Data on Abundance 48
Mixed Evergreen Forest 19
Coast Live Oak-California Bay- RESULTS AND DISCUSSION 51
Madrone Forest 19
Adas Coverage 51
Tanbark Oak-Madrone-
Patterns ofSpecies Richness ofthe
Live Oak-Douglas Fir Forest 19
BreedingAvifauna 51
Douglas Fir Forest 21
Oak Woodland and Oak Savannah 21 Distributional Highlights ofAdas Work 55
Bishop Pine Forest 21 Composition ofthe BreedingAvifauna 56
Coast Redwood Forest 22 Marin County Breeding Bird
Grassland 22 Communities 61
Coastal Prairie 22 Factors Limiting Species Richness ofthe Avifauna 61
Valley Grassland 23
Coastal Beach-Dune Vegetation 23 CONSERVATION APPLICATIONS 69
Northern Beach Association 23 How to Use This Book as a Conservation Tool 69
.
viI
CONTENTS
Identification ofBreeding Bird Species of NEW WORLD VULTURES
Special Concern 69 Turkey Vulture 125
HAWKS AND EAGLES
CONTENT OF SPECIES ACCOUNTS 73 Osprey 129
Adas Breeding Distribution Maps 73 Black-shouldered Kite 133
Northern Harrier 136
Key to Abundance and Distribution Data
AccompanyingAtlas Maps 73 Sharp-shinned Hawk 139
Cooper's Hawk 141
Seasonal Status 73
Red-shouldered Hawk 144
Breeding Status 73
Red-tailed Hawk 146
Blocks Recorded 75
Golden Eagle 148
Fine-Scale Abundance Rating(FSAR) 75
FALCONS
Relative Distribution Index (RDl) 75
American Kestrel 151
Overall Population Index (OPI) 75
Peregrine Falcon 154
Breeding Criteria Categories 75 PHEASANTS AND QUAIL
Confirmation Index (CI) 75
Ring-necked Pheasant 158
Content ofSpecies AccountText 76
California Quail 161
Ecological Requirements 76 RAILS, GALLINULES, AND COOTS
Marin Breeding Distribution 76
Black Rail 164
Historical Trends/Population Threats 76
Clapper Rail 166
Remarks 77
Virginia Rail 169
Observers 77
Sora 171
Abbreviations 77
Common Moorhen 172
SPECIES ACCOUNTS 79 PLAmOeVrEiRcaSn Coot 174
GREBES Snowy Plover 176
Pied-billed Grebe 79 Killdeer 179
STORM-PETRELS OYSTERCATCHERS
Ashy Storm-Petrel 81 Black Oystercatcher 181
CORMORANTS STILTS AND AVOCETS
Double-crested Cormorant 83 Black-necked Stilt 184
Brandt's Cormorant 85 American Avocet 187
Pelagic Cormorant 89 SANDPIPERS
BITTERNS AND HERONS Spotted Sandpiper 189
American Bittern 91 GULLS
Great Blue Heron 92 Western Gull 191
Great Egret 96 AUKS, MURRES, AND PUFFINS
Snowy Egret 98 Common Murre 194
Green-backed Heron 100 Pigeon Guillemot 197
Black-crowned Night-Heron 101 Rhinoceros Auklet 199
Recent Population Trends ofMarin County Tufted Puffin 201
Heron and Egret Colonies 103 PIGEONS AND DOVES
WATERFOWL Rock Dove 203
Canada Goose 104 Band-tailed Pigeon 205
Wood Duck 106 Mourning Dove 207
Mallard 109 ROADRUNNERS
Northern Pintail Ill Greater Roadrunner 209
Blue-winged Teal 113 BARN OWLS
Cinnamon Teal 115 Barn Owl 210
Northern Shoveler 116 TYPICALOWLS
Gadwall 118 Western Screech-Owl 213
Common Merganser 120 Great Horned Owl 215
Ruddy Duck 122 Northern Pygmy-Owl 217
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