Revised November 14, 2023

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######## 

######## U.S. Shorebird 

######## Conservation Plan

**Southern Pacific Coast**

**Regional Shorebird Plan**

**Version 1.0**

by

Gary W. Page and W. David Shuford

Point Reyes Bird Observatory

4990 Shoreline Highway

Stinson Beach, CA 94970

gpage@prbo.org

dshuford@prbo.org

**March 2000**

### CONTENTS

## EXECUTIVE SUMMARY ........................................................................1

Numbers of Shorebirds
.........................................................................1

Regional Importance of Shorebirds
...........................................................1

Threats to Shorebirds
...........................................................................2

Conservation Priorities
..........................................................................2

Tidal Wetlands
..............................................................................3

Managed Wetlands
..........................................................................3

Seasonal Coastal Wetlands
................................................................3

Coastal Beaches
.............................................................................3

Agricultural Land
...........................................................................3

Agricultural Evaporation Ponds
...........................................................4

######### Research Priorities ...........................................................................\....4

Monitoring Priorities
..................................................................\...
........4

Education Priorities
......................................................................
........5

Implementation and Coordination
.........................................................\....5

DESCRIPTION OF REGION
.....................................................................5

OCCURRENCE PATTERNS AND REGIONAL SPECIES PRIORITIES .................7

Species of Primary Importance in Region
...................................................7

Species of Importance in the Central Valley
............................................7

Species of Importance on the Coast
............................................... .......8

Species Equally Important on the Coast and in the Central Valley
..................8

Species of Secondary Importance in Region
................................................9

Species of Limited Importance in Region
...................................................9

NORTHERN CALIFORNIA COAST SUBREGION
.......................................\...9

Description of Subregion
.......................................................................9

Wetlands of Importance to Shorebirds
.......................................................9

Beaches of Importance to Shorebirds
.......................................................10

Pastures of Importance to Shorebirds
.......................................................11

Shorebird Species
..............................................................................11

Regional Population and Habitat Goals
....................................................11

Habitat Status, Threats, and Management Needs
.......................................\...12

Tidal Flats
..................................................................................12

Salt Marsh
..................................................................................13

Sand Beach and Dunes
....................................................................14

Rocky Shoreline
.........................................................................\...15

Offshore Waters
........................................................................\...15

Agricultural Lands and Seasonal Wetlands
............................................15

######### Monitoring Priorities ..........................................................................16

Research Priorities
.............................................................................16

Education Priorities
............................................................................16

Implementation and Coordination
...........................................................17

SAN FRANCISCO BAY SUBREGION
........................................................17

######### Description of Subregion ...................................................................\...17

Suisun Bay
...............................................................................\...17

##  North Bay ...................................................................................18

Central Bay
..............................................................................\...18

South Bay
...................................................................................19

Shorebird Species
..............................................................................19

Regional Population and Habitat Goals
.....................................................19

Habitat Status, Threats, and Management Needs
.......................................\...20

Tidal Flats
..................................................................................20

Salt Ponds
..................................................................................21

Managed Diked Marsh
....................................................................22

Salt Marsh
..................................................................................22

Agricultural Baylands
..................................................................\...23

All Habitats
..............................................................................\...23

Monitoring Priorities
........................................................................\...23

Research Priorities
.............................................................................23

Education Priorities
............................................................................24

Implementation and Coordination
...........................................................24

SOUTHERN CALIFORNIA COAST SUBREGION
.........................................25

######### Description of Subregion ...................................................................\...25

Wetlands of Importance to Shorebirds
......................................................25

Beaches of Importance to Shorebirds
.......................................................26

Shorebird Species
..............................................................................27

Regional Population and Habitat Goals
.....................................................28

Habitat Status, Threats, and Management Needs
.......................................\...28

Pajaro River Mouth
.....................................................................\...28

Elkhorn Slough
............................................................................29

Salinas River Mouth
......................................................................29

Morro Bay
..................................................................................29

Santa Maria River Mouth
.................................................................30

Devereaux Slough
.........................................................................30

Mugu Lagoon
..............................................................................30

Malibu Lagoon
.............................................................................31

Los Angeles River Mouth
................................................................31

San Gabriel River Mouth
.................................................................31

Seal Beach NWR
..........................................................................31

Bolsa Chica
..............................................................................\...32

Santa Ana River Mouth
..................................................................32

Upper Newport Bay
.......................................................................32

San Joaquin Marsh
........................................................................33

Santa Margarita River Mouth
.........................................................\...33

Agua Hedionda Lagoon
..................................................................33

Batiquitos Lagoon
.........................................................................34

San Elijo Lagoon
........................................................................\...34

San Dieguito Lagoon
.....................................................................34

Los Penasquitos Lagoon
...............................................................\...35

Misson Bay/San Diego Flood Control Channel
....................................\...35

San Diego Bay
.............................................................................35

Tijuana River Estuary
..................................................................\...36

Monitoring Priorities
........................................................................\...38

Research Priorities
.............................................................................38

Education Priorities
............................................................................39

Funding Priorities
...........................................................................\...39

Implementation and Coordination
...........................................................39

CENTRAL VALLEY SUBREGION
.........................................................\...40

######### Description of Subregion .....................................................................40

Shorebird Species
..............................................................................41

Regional Population and Habitat Goals
.....................................................43

Habitat Status, Threats, and Management Needs
.......................................\...43

##  Valleywide Habitat Status and Concerns ...............................................43

Overall Management Needs
..............................................................45

Managed Wetlands
........................................................................45

Agricultural Fields
........................................................................48

Agricultural Evaporation Ponds
.........................................................49

Sewage Ponds
...........................................................................\...50

Vernal Pool Rangelands
..................................................................50

Monitoring Priorities
........................................................................\...50

Research Priorities
.............................................................................51

Education Priorities
............................................................................51

Implementation and Coordination
...........................................................52

## CONTRIBUTORS .................................................................................52

Northern California Coast
..................................................................\...52

## San Francisco Bay ...........................................................................\...53

Southern California Coast
..................................................................\...53

Central Valley
..................................................................................53

## LITERATURE CITED ............................................................................55

APPENDIX: LIST OF COMMON AND SCIENTIFIC NAMES OF SHOREBIRD SPECIES CITED
IN THE TEXT
.........................................................\...61

## 

### EXECUTIVE SUMMARY

The 1,067-mile coastline and the 40-mile-wide by 400-mile-long Central
Valley of California are the main areas where shorebirds concentrate in
the Southern Pacific Region. Tidal wetlands, sand beaches, and rocky
shoreline are the principal shorebird habitats on the coast. About
two-thirds of the estimated 381,000 acres of prime tidal wetlands at the
turn of the century have been degraded or destroyed by agricultural,
industrial, urban, and military development (Speth 1979).
Simultaneously, sand beaches have been heavily developed for human
recreation and beach front housing, whereas rocky shoreline has been
relatively little altered. In the Central Valley, about 90% of historic
wetlands have been altered or destroyed for agriculture or urban
development. Today the Central Valley habitats most used by shorebirds
are restored, highly managed wetlands, irrigated or flooded agricultural
lands, hypersaline agricultural evaporation ponds, municipal sewage
ponds, and vernal pool rangelands.

**Numbers of Shorebirds**

Little quantitative information is available on historic shorebird
numbers in the region. Currently the Western Sandpiper is the most
abundant species with low millions passing through on migration and over
100,000 present during winter (Shuford et al. 1998, Page et al. 1999).
At least 250,000 Dunlin and likely over 100,000 Long-billed Dowitchers
winter in the area (PRBO unpubl. data). Over 100,000 Marbled Godwits,
Least Sandpipers, and Short-billed Dowitchers likely pass through during
migration (PRBO unpubl. data). Tens of thousands of Black-bellied
Plovers, Killdeer, Black-necked Stilts, American Avocets, Willets,
Marbled Godwits, Sanderlings, Least Sandpipers, and, probably, Black
Turnstones and Common Snipe winter in the region. Additionally, tens of
thousands of Whimbrels, Wilson's Phalaropes, and Red-necked Phalaropes
pass through during migration (PRBO unpubl. data).

**Regional Importance of Shorebirds**

Based on the proportion of the estimated North American population
occurring in the Southern Pacific Region, we ranked the region's
importance to species at three levels:

> *Primary Importance* -- Black-bellied Plover, Killdeer, Snowy Plover,
> Mountain Plover, Black Oystercatcher, American Avocet, Greater
> Yellowlegs, Willet, Whimbrel, Long-billed Curlew, Marbled Godwit,
> Black Turnstone, Western Sandpiper, Dunlin, Short-billed Dowitcher,
> Long-billed Dowitcher, Common Snipe, and Red Phalarope.
>
> *Secondary Importance* -- Semipalmated Plover, Black-necked Stilt,
> Wandering Tattler, Spotted Sandpiper, Red Knot, Sanderling, Least
> Sandpiper, Wilson's Phalarope, and Red-necked Phalarope.
>
> *Limited Importance* -- American Golden-Plover, Pacific Golden-Plover,
> Lesser Yellowlegs, Solitary Sandpiper, Ruddy Turnstone, Surfbird,
> Semipalmated Sandpiper, Baird's Sandpiper, Pectoral Sandpiper, and
> Rock Sandpiper.

Of all species, the Snowy Plover, Mountain Plover, Long-billed Curlew,
and Marbled Godwit are considered the highest priority species for
conservation actions in the region based on their high national
rankings.

**Threats to Shorebirds**

Shorebirds of this region have experienced high levels of habitat
alteration from agricultural and urban development over the past two
centuries. Ongoing urban development is highly likely to remain an agent
of habitat loss, especially in agricultural lands of the Central Valley.
In this region, changes in cropping patterns -- such as from rice to
cotton or from cattle grazing to viticulture -- also may reduce the
value of agricultural land to shorebirds. Expanding urbanization also
may in the future reduce the supply of water available for wetlands and
agriculture. Accelerated wetland sedimentation from watershed
alteration, exacerbated by infrastructure construction within wetlands,
is an ongoing problem that has reduced tidal prism and circulation at
several coastal wetlands. Watershed run-off or point discharges have
contaminated sediments or water at some inland and coastal locations.
The spread of exotic plants -- such as European beachgrass *(Ammophila
arenaria)* on coastal beaches or salt-water cord grass *(Spartina
alterniflora)* in San Francisco Bay -- has reduced or, in the latter
example, threatens to reduce the extent of shorebird habitat. The
ongoing introduction of many non-native invertebrates into the benthos
of coastal wetlands, through ship ballast discharges and other human
activities, is regularly altering the composition of potential shorebird
prey in an unpredictable manner. Mosquito abatement programs limit
options for habitat management, especially the flooding of inland
wetlands during summer. Various oyster culture practices affect
shorebird access to potential food resources in species-specific ways
(Kelly et al. 1996). Nesting shorebirds in the region have experienced
high rates of nest loss to introduced mammalian predators, especially
the red fox *(Vulpes vulpes)*, and to expanding populations of native
predators, especially the Common Raven *(Corvus corax)*. Growing
recreational use of beaches and wetlands appears to be causing increased
disturbance of roosting and foraging shorebirds. As shorebirds today
live in an environment quite different from two centuries ago, we
conclude that shorebird conservation in the Southern Pacific Region will
require substantial effort just to maintain current populations.

**Conservation Priorities**

Priorities for conservation of shorebird populations in the Southern
Pacific Region are to:

-   Increase breeding populations of the Snowy Plover to 2,750 breeding
    adults, as recommended in the draft USFWS Snowy Plover Recovery
    Plan, and double the Central Valley population. On the coast, the
    Recovery Plan is expected to recommend closing some nesting areas to
    the public, protecting nests with exclosures and predator
    management, and restoring nesting habitat through removal of exotic
    vegetation, especially European beachgrass (*Ammophila arenaria)*.
    In the Central Valley, plover numbers should be increased by
    creating more saline wetland habitat.

-   Increase or maintain breeding populations of the Killdeer, Black
    Oystercatcher, Black-necked Stilt, and American Avocet by enhancing,
    restoring, or creating nesting habitat.

-   Increase migratory and wintering populations of all key shorebird
    species in the region by protecting existing habitat, managing
    existing habitat more for shorebirds, and creating more shorebirds
    habitat.

    Recommended actions for specific habitats are to:

    *Tidal Wetlands*

-   Restore tidal flats and marshes, particularly in San Francisco Bay
    and on the southern California coast.

-   Enhance tidal action in existing wetlands as needed.

-   Reduce sedimentation from alteration of wetland watersheds.

-   Oppose further fragmentation of wetlands by human infrastructure
    such as roads and power lines.

-   Minimize future introductions of non-native invertebrates and
    plants.

-   Eliminate the exotic plant *Spartina alterniflora* from mudflats,
    especially in San Francisco Bay.

-   Oppose further development of tidal flats for oyster culture on the
    northern California coast.

-   Control human disturbance.

    *Managed Wetlands*

-   Create and enhance managed wetlands, especially in the Central
    Valley.

-   Improve the value of managed wetlands to shorebirds by incorporating
    features such as undulating pond bottoms, gentle levee slopes, and
    underwater berms.

-   Expand current wetland management strategies to benefit shorebirds,
    particularly by lowering winter water levels and regulating the
    timing and staggering of late-winter and spring drawdowns.

-   Avoid further fragmentation and encroachment of wetlands by
    development.

-   Manage vegetation succession to benefit shorebirds.

-   Retain and manage some salt ponds in San Francisco Bay for
    shorebirds.

*Seasonal Coastal Wetlands*

-   Protect coastal seasonal wetlands from development.

    *Coastal Beaches*

-   Rank beaches by importance to shorebirds and restrict dogs on
    highest ranked beaches.

-   Enforce dog leash laws on all beaches.

-   Limit other human disturbance of shorebirds on beaches.

-   Eliminate exotic plants such as *Ammophila arenaria*.

    *Agricultural Land*

-   Protect agricultural land for shorebirds through conservation
    easements.

-   Promote management of agricultural land for shorebirds.

-   Promote conventional methods of rice harvest and shallow flooding of
    riceland in winter.

-   Increase acreage of flooded riceland in winter.

-   Curtail the rapid loss of vernal pool rangelands.

    *Agricultural Evaporation Ponds*

-   Reduce shorebird use of contaminated agricultural evaporation ponds
    in the San Joaquin Valley while creating nearby mitigation wetlands,
    particularly saline habitats mimicking historic playa lakes.

    **Research Priorities**

    Regional research priorities are to:

-   Investigate the extent and reasons why shorebirds move between
    different wetland complexes and what degree of site fidelity they
    exhibit.

-   Identify the factors limiting shorebird abundance and whether these
    factors are intrinsic or extrinsic to the region.

-   Study how various human disturbances effect shorebirds, including
    impacts on prey ingestion rates, energy intake, body condition, and
    survival.

-   Determine seasonal and habitat variation in shorebird diets in
    managed wetlands, the effect of different water drawdown techniques
    on invertebrate prey production and availability, and how shorebirds
    respond to different management techniques.

-   Study how different oyster culture techniques vary with respect to
    sedimentation rates, benefits to foraging shorebirds, and levels of
    human disturbance.

-   Experiment with managing salt ponds for shorebirds in the absence of
    commercial salt production.

-   Investigate the effect of introduced invertebrates on shorebird
    feeding ecology.

-   Identify which beaches are most important to migrating and wintering
    shorebirds.

-   Learn more about habitat use, nesting success, and adult and
    juvenile survival rates of Snowy Plovers in San Francisco Bay.

-   Determine the current size and distribution of the breeding
    populations of the American Avocet and Black-necked Stilt in the
    region and the best methods of creating good nesting habitat for
    these species.

-   Identify the breeding range of the small population of the Red Knot
    that uses the region during migration and winter and the wintering
    range on the coast of the small population of the Marbled Godwit
    that breeds in Alaska.

-   Investigate whether reproductive success of the Black Oystercatcher
    is impacted by human disturbance or the expanding Common Raven
    population in the region.

    **Monitoring Priorities**

    Regional monitoring priorities are to:

-   Develop and implement techniques to assess long-term trends in
    shorebird abundance.

-   Quantify success of restoration projects in meeting shorebird
    objectives.

-   Monitor long-term trends in habitat availability.

-   Determine trends in abundance of shorebird predators, especially the
    Merlin (*Falco columbarius)*, Peregrine Falcon *(Falco peregrinus)*,
    and Short-eared Owl *(Asio flammeus)*.

-   Monitor annual numbers, nesting success, and survival of the Snowy
    Plover on the coast.

-   Conduct annual winter surveys of Mountain Plover numbers.

    **Education Priorities**

    Programs should be developed to educate the public about shorebirds
    and their habitat needs, create sympathy for shorebirds, and provide
    guidance about what should and should not be done to help
    shorebirds. Efforts also should focus on generating interest among
    resource managers in shorebirds and their protection and advising
    them of the most up-to-date techniques for habitat restoration,
    enhancement, and management for shorebirds.

    **Implementation and Coordination**

    A Working Group should be formed to guide implementation of the
    goals and priorities of the shorebird conservation plan in the
    Southern Pacific Region. The Working Group's efforts should be
    coordinated through the Pacific Coast Joint Venture, San Francisco
    Bay Joint Venture, and Central Valley Habitat Joint Venture, all of
    which currently are active in parts of the area. A coordinator
    should be hired for the southern California coast (Golden Gate to
    Mexico border), where there currently is no active Joint Venture to
    implement the plan.

    **DESCRIPTION OF REGION**

    The Southern Pacific Region of the U. S. Shorebird Conservation Plan
    lies completely within the state of California and adjacent U.S.
    territorial waters. It is bounded seaward by the 200 mile limit and
    inland by the Cascade and Sierra Nevada mountains. The Southern
    Pacific Region overlaps two Bird Conservation Regions (BCR) -- part
    of the Pacific Northwest BCR and all of the Coastal California BCR.
    The Coastal California BCR includes the Central Valley of
    California.

    All or parts of three Joint Ventures of the North American Waterfowl
    Management Plan are included within the Southern Pacific (shorebird)
    Region. The Pacific Coast Joint Venture includes all of the portion
    of the Pacific Northwest BCR within the Southern Pacific (shorebird)
    Region and overlaps a small part of the Coastal California BCR. The
    San Francisco Bay Joint Venture and the Central Valley Habitat Joint
    Venture are both completely contained within the Coastal California
    BCR.

    For planning purposes, the Southern Pacific Region is divided into
    the following subregions: Northern California Coast, Southern
    California Coast, San Francisco Bay, and Central Valley. Within the
    Southern Pacific Region, the major areas of shorebird concentration
    are the coast, offshore waters (used by migrating phalaropes), and
    the Central Valley. The coast consists of rocky and sandy shoreline
    interspersed with wetlands. Shorebirds' main native coastal habitats
    are tidal sand and mud flats, marshes, rocky shores, and sand
    beaches. Within San Francisco and San Diego bays, some commercial
    salt evaporation ponds are important habitat for shorebirds. Diked
    wetlands, sewage ponds, and agricultural lands, especially heavily
    grazed pastures, are other human-created habitats along the coast
    that support shorebirds. The natural wetlands of the coast have been
    greatly altered by human activities during the past 200 years. So
    much wetland habitat has been degraded or destroyed that all
    remaining habitat supporting shorebirds should be preserved or
    enhanced.

    In the Central Valley, over 90% of the historic wetlands have been
    altered by agricultural and urban development. At present, key
    shorebird habitats in the Central Valley are restored, highly
    managed wetlands, irrigated or flooded agricultural lands,
    hypersaline agricultural evaporation ponds, and municipal sewage
    ponds. Shorebird use of agricultural lands is concentrated primarily
    in Sacramento Valley rice fields and secondarily in various plowed
    croplands, alfalfa fields, irrigated pastures, and vernal pool
    rangelands.

    The Southern Pacific Region is an important wintering area for
    shorebirds that breed in the arctic and temperate zones. For
    example, it is a wintering area for the Dunlin, Willet, and Marbled
    Godwit, which, respectively, nest in Alaska, the Great Basin, and
    the Prairie. The region also is important during migration,
    particularly for arctic-breeding species such as the Whimbrel,
    Western Sandpiper, and Short-billed Dowitcher. Numbers of these
    shorebirds in the region swell during migration periods, which, for
    all species combined, extend primarily from mid-March to mid-May in
    spring and from mid-June until at least November in autumn. Species
    with important breeding populations in the region include the Snowy
    Plover, Killdeer, Black Oystercatcher, Black-necked Stilt, and
    American Avocet; ones with less significant breeding populations
    include the Spotted Sandpiper, Common Snipe, and Wilson's Phalarope.

    A variety of factors impact shorebird use of the Southern Pacific
    Region. Historic loss and degradation of native wetlands and
    shorebirds' exploitation of human-created habitats undoubtedly has
    altered the abundance and distribution of shorebirds in the region.
    An increase in sedimentation rates over historical levels, from
    human alteration of watersheds, threatens to shorten the life spans
    of some coastal wetlands that are now otherwise protected.
    Introductions of marsh plants to some large wetlands threaten to
    reduce the area of unvegetated tidal flats and hence prime foraging
    habitats for shorebirds. Continually changing benthic invertebrate
    communities, as a result of ship ballast discharges and other human
    activities, may impact the food resources of many shorebird species.

    While there is considerable effort being made to restore wildlife
    habitat and listed species along the coast and in the Central
    Valley, there can be competing needs of other species. For example,
    recovery of the endangered Peregrine Falcon has likely increased
    winter mortality of shorebirds as shorebirds are important peregrine
    prey. Restoring tidal marshes for the recovery of listed populations
    of marsh-dependent species, such as the California Clapper Rail
    *(Rallus longirostris obsoletus)* and Salt Marsh Harvest Mouse
    *(Reithrodontomys raviventris),* could reduce the extent of other
    habitats, such as salt ponds, that may be more valuable than marshes
    to shorebirds. In the Central Valley, the focus on habitat
    restoration for waterfowl often results in wetland water levels too
    deep for shorebirds.

    Competition among agriculture, urban populations, and wildlife for a
    limited water supply may hamper wetland habitat restoration for all
    species. Even when water is available, the manner and timing with
    which it can be applied to wetlands is restricted by mosquito
    abatement regulations designed to control and prevent human
    diseases.

    The growing demand of an expanding human population for recreational
    opportunities threatens coastal habitats and especially beaches,
    which are an important nesting habitat for the threatened Snowy
    Plover and a foraging habitat for the plover and other shorebirds.
    On beaches, shorebirds are flushed regularly by pedestrians,
    joggers, and, especially, unleashed dogs, which sometimes
    intentionally chase shorebirds. Snowy Plover nests have been stepped
    on by pedestrians and equestrians and have been destroyed by dogs.
    People also have deliberately destroyed plover nests at some
    locations (PRBO unpubl. data).

    **OCCURRENCE PATTERNS AND REGIONAL SPECIES PRIORITIES**

    Thirty-seven species of shorebirds occur regularly within the
    Southern Pacific Region (see Appendix for scientific names). Based
    on the proportion of the estimated North American population
    occurring in the Southern Pacific Region, we ranked the region's
    importance to species at three levels:

    **Species of Primary Importance in Region**

    Eighteen species were ranked of primary importance because their
    regional populations likely are as high (during one or more seasons)
    as those in the majority of other shorebird planning regions in the
    United States. Of the 18 species for which the region stands out,
    largest numbers and principal habitats of 6 are in the Central
    Valley and of 8 are on the coast, whereas 4 are relatively abundant
    in both coastal and inland habitats.

    *Species of Importance in the Central Valley. T*he six species for
    which the Central Valley is particularly important are:

    Killdeer -- The Killdeer is of primary importance in the Southern
    Pacific Region because of the large number of wintering birds in the
    Central Valley. About 11,000 to 17,000 Killdeer have been counted in
    the Central Valley in mid-winter, but those surveys did not include
    upland habitats used by many individuals (Shuford et al. 1998).
    Large numbers also nest in the Central Valley, particularly in and
    adjacent to the extensive area of Sacramento Valley rice fields (D.
    Shuford pers. obs.).

## Mountain Plover -- The majority of the Mountain Plover's entire population winters in California, primarily in the Central and Imperial valleys (Hunting and Fitton 1999). Thousands of wintering Mountain Plovers were regularly recorded in the San Joaquin Valley (southern drainage of the Central Valley) in the 1960s, but numbers have dwindled considerable in recent decades (J. Engler in litt.). The Mountain Plover currently is proposed for listing as a federally Threatened Species. Because of its imperiled status and its concentration in the Central Valley in winter, this species is of primary importance for the Southern Pacific Region.  {#mountain-plover-the-majority-of-the-mountain-plovers-entire-population-winters-in-california-primarily-in-the-central-and-imperial-valleys-hunting-and-fitton-1999.-thousands-of-wintering-mountain-plovers-were-regularly-recorded-in-the-san-joaquin-valley-southern-drainage-of-the-central-valley-in-the-1960s-but-numbers-have-dwindled-considerable-in-recent-decades-j.-engler-in-litt..-the-mountain-plover-currently-is-proposed-for-listing-as-a-federally-threatened-species.-because-of-its-imperiled-status-and-its-concentration-in-the-central-valley-in-winter-this-species-is-of-primary-importance-for-the-southern-pacific-region. .unnumbered}

## Greater Yellowlegs -- This species is of primary importance in the region because of its large winter numbers in the Central Valley. Using a combination of aerial and ground surveys, Shuford et al's (1998) counts averaged about 4,000 Greater Yellowlegs each winter in the Central Valley, but these undoubtedly are underestimates. From his surveys of rice fields, Chris Elphick (in litt.) extrapolated that roughly 12,300 (confidence interval 3,000-21,600) Greater Yellowlegs winter in Sacramento Valley rice fields. {#greater-yellowlegs-this-species-is-of-primary-importance-in-the-region-because-of-its-large-winter-numbers-in-the-central-valley.-using-a-combination-of-aerial-and-ground-surveys-shuford-et-als-1998-counts-averaged-about-4000-greater-yellowlegs-each-winter-in-the-central-valley-but-these-undoubtedly-are-underestimates.-from-his-surveys-of-rice-fields-chris-elphick-in-litt.-extrapolated-that-roughly-12300-confidence-interval-3000-21600-greater-yellowlegs-winter-in-sacramento-valley-rice-fields. .unnumbered}

Whimbrel -- This species is of primary importance in the region because
a minimum of about 8,000 migrate through the Central Valley in spring
(Shuford et al. 1998).

Long-billed Dowitcher -- Since over 90,000 Long-billed Dowitchers occur
in the Central Valley during midwinter and spring (Shuford et al. 1998),
the Southern Pacific Region is of primary importance for this species.

Common Snipe -- Although no accurate estimates are available, there
likely are tens of thousands of snipe in the Central Valley in winter,
indicating the region is of primary importance for this species.

###  {#section-2 .unnumbered}

### *Species of Importance on the Coast.* The eight species for which coastal habitats in the Southern Pacific Region are especially important are: {#species-of-importance-on-the-coast.-the-eight-species-for-which-coastal-habitats-in-the-southern-pacific-region-are-especially-important-are .unnumbered}

Black-bellied Plover -- This species is of primary importance in the
region because at least 28,500 birds winter and 42,500 migrate along the
coast (PRBO unpubl. data).

Snowy Plover -- This plover is of primary importance in the region
because over 90% of the listed population along the U.S. Pacific Coast
breeds here (U.S. Fish and Wildlife Service draft recovery plan) and
most of it also winters here. Snowy Plovers from the Central Valley and
western Great Basin also winter along the region's coastline (Page et
al. 1995a*).*

Black Oystercatcher -- The oystercatcher is of primary importance in the
region because it is limited in distribution to the west coast of the
United States, and, hence, the Southern Pacific Region is one of three
U.S. shorebird planning regions in which the species is found. Its
primary habitat is outer coast rocky shoreline. Carter et al. (1992)
recorded 888 Black Oystercatchers on the California coast during a
statewide survey of nesting seabirds from 1989 to1991. Although
comparable data are lacking, similar numbers appear to occur year round.

Willet -- The species' regional importance is based on the 20,000+
Willets that winter along the California coast and the 50,000+ that may
migrate through the coastal region (PRBO unpubl. data).

Marbled Godwit -- The region is of primary importance to this species
because an estimated 37,000 occur along the California coast in winter
(PRBO unpubl. data), and up to 138,000 may pass through during
migration, assuming the majority of birds wintering in Baja California,
Mexico (Page et al. 1997), migrate through California. Wintering numbers
on the California coast are unmatched elsewhere in the United States.

Black Turnstone -- Because wintering Black Turnstones are restricted to
the three shorebird planning regions on the west coast of the United
States, the Southern Pacific Region is of primary importance for this
species. Black Turnstones forage on rocky outer coast shoreline and
estuarine tidal flats.

Short-billed Dowitcher -- The region is of primary importance for this
species because as many as 150,000 Short-billed Dowitchers probably
migrate along the California coast in spring (PRBO unpubl. data).

Red Phalarope -- The region is of primary importance for this species
because the entire western population migrates over offshore waters off
California.

###  {#section-3 .unnumbered}

### *Species Equally Important on the Coast and in the Central Valley.* The final four species for which the region is particularly important, and that are relatively abundant both on the coast and in the Central Valley, are: {#species-equally-important-on-the-coast-and-in-the-central-valley.-the-final-four-species-for-which-the-region-is-particularly-important-and-that-are-relatively-abundant-both-on-the-coast-and-in-the-central-valley-are .unnumbered}

Long-billed Curlew -- The region is of primary importance to the curlew
because it holds a large percentage of the species' wintering
population. Pacific Flyway project surveys found at least 7,000 curlews
in the region in winter (PRBO unpubl. data), but this is a minimum
estimate because of a lack of surveys in upland habitats of the Central
Valley. G. Morrison (in litt.) estimates the North American population
at 20,000 birds.

Western Sandpiper -- The region is of primary importance to this species
because over one million Western Sandpipers migrate through the Central
Valley and along the coast during spring (PRBO unpubl. data). The entire
world population of this species is approximately 2.5 to 4.0 million
birds (M. Bishop in litt.).

Dunlin -- The region is of primary importance to the species because the
minimum estimate of 250,000 individuals of the race *C. a. pacifica*
that winter along the coast and in the Central Valley (PRBO unpubl.
data) represents about one half of that subspecies' entire population
(Page and Gill 1994).

American Avocet -- The region is of primary importance to the species
because avocet numbers here in winter may be greater than those in any
other planning region and in fall may be surpassed only by numbers in
the Intermountain Region.

**Species of Secondary Importance in Region**

Nine species were ranked of secondary importance because their regional
populations likely are as high as those in only several other regions.
These species are: Semipalmated Plover (on coast and inland during
migration and winter), Black-necked Stilt (on coast and inland year
round), Wandering Tattler (on coast during migration), Spotted Sandpiper
(on coast and inland during migration and winter), Red Knot (on coast
during migration and winter), Sanderling (on coast during migration and
winter), Least Sandpiper (on coast and inland during migration and
winter), and Wilson's and Red-necked phalaropes (on coast and in Central
Valley wetlands during migration).

**Species of Limited Importance in Region**

Ten species were ranked of limited importance because their regional
populations likely are very small relative to those in other regions.
These species are: American Golden-Plover, Pacific Golden-Plover, Lesser
Yellowlegs, Solitary Sandpiper, Ruddy Turnstone, Surfbird, Semipalmated
Sandpiper, Baird's Sandpiper, Pectoral Sandpiper, and Rock Sandpiper.

**NORTHERN CALIFORNIA COAST SUBREGION**

**Description of Subregion**

The northern California coast extends about 419 miles from the Oregon
border south to the entrance of San Francisco Bay. About 40% of the
coastline is sand beach, nearly half of which is backed by sand dunes;
about 59% is rocky (U.S. Army Corps of Engineers 1971).

**Wetlands of Importance to Shorebirds**

Along the coast 10 wetlands are known to hold over 1,000 shorebirds
during peak periods of occurrence. Seven wetlands are exposed to
continuous tidal action and three are usually isolated from the ocean by
barrier bars. From north to south by county these wetlands are:

###### Del Norte County {#del-norte-county .unnumbered}

*S*mith River mouth -- this open river estuary has held up to 4,000
shorebirds in fall (PRBO unpubl. data).

Lake Talawa -- this brackish lagoon, separated from the ocean by a
barrier bar (Funderburk and Springer 1989), has held over 13,000
shorebirds (PRBO unpubl. data).

*Humboldt County*

Humboldt Bay (including the Eel River mouth) -- this large estuary is
recognized as a site of International Importance for shorebirds by the
Western Hemisphere Shorebird Reserve Network (WHSRN). Depending on
season 20,000 to 80,000 shorebirds reside in Humboldt Bay (Colwell
1994).

*Sonoma County*

Bodega Harbor -- this 850-acre estuary regularly holds 2,000 to 6,000
shorebirds and sometimes over 12,000 in winter (PRBO unpubl. data).

*Marin County*

Estero Americano -- this wetland is often cut-off from the tides by a
barrier bar, but when open to daily tidal influence, has 1,000 to 3,000
shorebirds in fall and winter (PRBO unpubl. data).

Tomales Bay -- this 8,658-acre coastal embayment holds 5,000 to 10,000
shorebirds in spring and fall and up to 20,000 in winter (PRBO unpubl.
data), thereby qualifying it as a potential WHSRN site of Regional
Importance.

Abbotts Lagoon -- this 212-acre wetland consists of three
fresh-to-brackish ponds separated from the ocean by a barrier bar.
During low tide shorebird numbers are usually in the hundreds but at
high tide they may exceed 1,000 from movement of birds from nearby
Drakes Estero.

Drakes and Limantour esteros -- these two esteros are best considered as
a single wetland system because of their common entrance to the ocean
and the regular interchange of shorebirds between them. The 1,816-acre
Drakes Estero is managed partly for mariculture and the 481-acre
Limantour Estero is an Ecological Reserve. Each regularly holds
thousands of shorebirds with combined totals sometimes reaching nearly
20,000 individuals in winter (PRBO unpubl. data). Together they could
qualify as a WHSRN site of Regional Importance.

Bolinas Lagoon -- this 1,100-acre, very shallow estuary regularly holds
5,000 to 10,000 shorebirds (PRBO unpubl. data); during spring migration,
numbers have been known to swell to 35,000 (Shuford et al. 1989).
Bolinas Lagoon is recognized as a Ramsar site of International
Importance to waterbirds and also would qualify as a WHSRN site of
Regional Importance.

**Beaches of Importance to Shorebirds**

Sand beaches associated with wetlands are usually the ones most heavily
used by shorebirds in this region. These include the beach at Lake
Talawa, Mad River sand spit, beaches to the north and south of the Eel
River mouth, sand beaches associated with Humboldt Bay (Colwell and
Sundeen in press), Salmon Creek and Doran beaches at Bodega Harbor,
Dillon Beach at the entrance of Tomales Bay, Point Reyes Beach at
Abbotts Lagoon, the sand spits of Drakes and Limantour esteros, and
Bolinas Lagoon spit. Not only are these beaches (except Dillon Beach)
current or historic breeding and foraging areas for the Snowy Plover
(Page and Stenzel 1981) and foraging areas for Sanderlings and other
shorebirds, they also are important high tide roosting sites for many
species of shorebirds that forage on tidal flats at low tide.

**Pastures of Importance to Shorebirds**

Pastures with associated seasonal wetlands are habitat for shorebirds at
the Eel River delta, Humboldt Bay (Colwell and Dodd 1997), Tomales Bay,
Drakes Estero, and Bolinas Lagoon (Page et al. 1979). Tilled land at
Drakes Estero and Bolinas Lagoon is also used by foraging shorebirds in
winter.

**Shorebird Species**

Humboldt Bay lies at or near the northern boundary of the coastal
wintering range of several species that breed at temperate latitudes. It
is the northernmost wintering area for the American Avocet, and one of
the most northern wintering areas for the Long-billed Curlew, Marbled
Godwit, and Willet (Page et al. 1999). Besides their importance for
wintering shorebirds from temperate zone breeding areas, northern
California coastal wetlands are important wintering areas for species
with arctic-breeding ranges, such as the Black-bellied Plover, Western
Sandpiper, Least Sandpiper, and Dunlin. During migration, these wetlands
are used by even larger numbers of Western Sandpipers than in winter.
Other shorebirds migrating through the wetlands, particularly during
spring, are the Semipalmated Plover, Whimbrel and Short-billed
Dowitcher.

The rocky shoreline of the region is occupied by resident Black
Oystercatchers and thousands of wintering Black Turnstones. Other
species that use the rocky coast of the region, though in relatively
small numbers, are the Wandering Tattler, Spotted Sandpiper, Whimbrel,
Ruddy Turnstone, Surfbird, and Rock Sandpiper.

The sand beaches in this subregion are used by large numbers of
migrating and wintering Sanderling and are important nesting areas for
the Snowy Plover. During the mid-1970s over 100 plovers nested along the
region's beaches (Page and Stenzel 1981) but the number is probably less
than half that today (PRBO unpubl. data). Other species for which sand
beaches are relatively important foraging areas during migration or
winter are the Willet and Whimbrel. Beaches associated with wetlands are
important high tide roosting sites for many species of shorebirds that
forage in the wetlands at low tide (Colwell and Sundeen in press).

The offshore waters of the region are used by large numbers of migrating
Red-necked and Red phalaropes (Briggs et al. 1987).

Agricultural lands, especially pastures and associated seasonal
wetlands, are important foraging and roosting habitat for many species
of shorebirds during winter and spring. Such areas are most heavily used
during high tides when tidal habitats are unavailable. The Black-bellied
Plover, Killdeer, Greater Yellowlegs, Long-billed Curlew, Marbled
Godwit, Least Sandpiper, Dunlin, and Long-billed Dowitcher are
characteristic shorebirds of these habitats (Colwell and Dodd 1997).

**Regional Population and Habitat Goals**

Priority population and habitat conservation goals for the northern
California coast are to:

-   Attain a breeding population of 210 Snowy Plovers, consistent with
    the objectives of the draft USFWS Snowy Plover Recovery Plan.

-   Maintain current numbers of breeding Black Oystercatchers.

-   Maintain numbers of all migrant and wintering shorebirds at current
    levels.

-   Restore mudflats and tidal action in coastal wetlands to compensate
    for past habitat loss and degradation.

-   Eliminate *Ammophila arenaria* from beaches to improve Snowy Plover
    nesting habitat.

-   Protect tidal flats from excessive sedimentation from wetland
    watershed alteration.

-   Protect existing tidal flat habitat from introduced invertebrates
    and plants.

-   Limit human disturbance of nesting, feeding, and roosting shorebirds
    in all habitats.

    **Habitat Status, Threats, and Management Needs**

###### Descriptions of historical and current habitat availability, shorebird habitat use patterns, threats to shorebirds, management issues, and needed conservation actions are provided below for the major habitat types in the region. {#descriptions-of-historical-and-current-habitat-availability-shorebird-habitat-use-patterns-threats-to-shorebirds-management-issues-and-needed-conservation-actions-are-provided-below-for-the-major-habitat-types-in-the-region. .unnumbered}

*Tidal Flats.* No regional estimates are available of the total current
acreage of tidal flat, the most important shorebird habitat within the
coastal embayments of northern California. Tidal flat is the primary
foraging habitat of many of the region's most abundant shorebirds,
including the Black-bellied Plover, Semipalmated Plover, Willet,
Long-billed Curlew, Marbled Godwit, Western Sandpiper, Least Sandpiper,
Dunlin, and Short-billed Dowitcher. The main shorebird prey in the tidal
flats are invertebrates, but many of these are introduced species that
arrived through the release of ship ballast and other human actions.
Invertebrate introductions are ongoing with unknown consequences for
shorebirds. Introduced invertebrates are prominent in the benthos of
Humboldt Bay, Bodega Harbor, Estero Americano, and Bolinas Lagoon. They
probably also are an important element of the invertebrate benthos of
Tomales Bay, Drakes Estero, and Limantour Estero.

Historic loss of tidal habitat from diking or filling has occurred at
Humboldt Bay, Bodega Harbor, Estero Americano, Drakes Estero, Tomales
Bay, Limantour Estero, and Bolinas Lagoon. Accelerated sedimentation of
tidal habitat from historic or ongoing logging or grazing in the
watershed has been identified for Humboldt Bay, Bodega Harbor, Estero
Americano, Tomales Bay, and Bolinas Lagoon. It also may be occurring at
Drakes Estero. Impaired tidal circulation has been identified for Estero
Americano, and parts of Tomales Bay, Drakes Estero, and Bolinas Lagoon.

Oyster farming occurs in Humboldt Bay, Tomales Bay, and Drakes Estero.
Oyster farming influences shorebird use of tidal flat by enhancing
feeding opportunities for some species, such as the Willet, while
decreasing them for others, such as the Dunlin (Kelly et al. 1996).
Oyster culture may have increased sedimentation rates at Drakes Estero
(S. Allen pers. comm.). The effect of oyster culture practices on
sedimentation/erosion of tidal flats should be considered in future
leases.

Disturbance from human recreation is a potential problem for shorebirds
at Lake Talawa, Humboldt Bay, Bodega Harbor, Tomales Bay, Drakes Estero,
and Bolinas Lagoon. Specific disturbance agents include wind surfers at
Humboldt Bay and Bodega Harbor; dogs chasing birds on tidal flats at
Humboldt Bay and Bodega Harbor; people involved in intensive clam
harvesting at Tomales Bay and Bodega Harbor; and kayakers at Tomales
Bay, Drakes Estero, and Bolinas Lagoon. A study has been proposed at
Bolinas Lagoon to determine the degree of disturbance caused by kayakers
and the value of educational efforts to lessen this source of
disturbance (G. Page pers obs.). Restrictions on kayaking in Drakes
Estero from March to June, to reduce disturbance to harbor seals *(Phoca
vitulina),* probably also reduces human disturbance of spring-migrating
shorebirds (S. Allen pers. comm.).

Contaminants, in the form of non-point pollution sources from
neighboring cities, were identified as possibly detrimental to
shorebirds at Humboldt Bay (M. Colwell pers. comm.). Oil spills pose a
threat to the intertidal habitats of all the wetlands open to daily
tidal action, and sea level rise could effect the extent of tidal flat
habitat in all the wetlands.

Priority conservation actions for tidal flats are to:

-   Improve and revise watershed management actions for all coastal
    wetlands to reduce sediment accumulation on intertidal habit.

-   Restrict use of jet skis in wetlands where they are found to be a
    major source of disturbance to shorebirds.

-   Support legislation restricting ballast discharge to reduce the
    probability of new invertebrate introductions into coastal wetlands.

-   Maintain levee breaks to retain tidal flats currently used by
    shorebirds at the Eel River Wildlife Area.

-   Prohibit further alteration of tidal flats for oyster culture at
    Humboldt Bay, Tomales Bay, and Drakes Estero.

-   Maintain continuous tidal exchange by breaching the barrier bar
    after closures at Estero Americano.

-   Breach levees to restore mud flat and tidal marsh in diked pastures
    at Giacomini Ranch, Tomales Bay. An estimated 90 acres of tidal flat
    could be restored through this action (Philip Williams and
    Associates et al. 1993).

-   Increase tidal circulation in the leveed marsh at Tomasini Point,
    Tomales Bay; examine the potential benefit of a similar action for
    leveed marsh at Bivalve Point.

-   Develop a management plan for the large sandbars north of Tom's
    Point, Tomales Bay to limit the effect of claming and other
    recreational activities on foraging shorebirds.

-   Increase tidal flat and tidal circulation by removing levees at the
    Glenbrook and Muddy Hollow ponds, Limantour Estero.

-   Restrict kayaking during periods of peak shorebird occurrence at
    Drakes and Limantour esteros.

-   Support the U.S. Army Corps of Engineers study to improve the tidal
    circulation and increase the tidal prism at Bolinas Lagoon.

    *Salt Marsh.* Shorebirds use salt marsh to a lesser degree than
    tidal flats. Salt marsh vegetation, growing in the upper part of the
    intertidal zone, may be too tall or dense to provide much foraging
    habitat for shorebirds. The larger non-vegetated channels in salt
    marsh are used as foraging habitat by the same species that feed on
    tidal flats. Some species, such as the Willet, Whimbrel, Long-billed
    Curlew, and Least Sandpiper, also forage on marsh plains with sparse
    or low vegetation (\< about 8 inches). Species such as the Willet,
    Least Sandpiper, Dunlin, and Long-billed Dowitcher use salt marsh as
    nocturnal roost sites, possibly to provide some protection from
    predators such as owls. Inclusion of channels in marsh restoration
    projects should be promoted to benefit shorebirds, but the spread of
    salt marsh at the expense of tidal flats should be considered more
    detrimental than beneficial to most shorebirds.

    A priority conservation action for salt marshes is to:

-   Eliminate the introduced salt-water cord grass (*Spartina
    alterniflora)* from the mudflats at Humboldt Bay.

    *Sand Beach and Dunes.* The region has about 166 miles of outer
    coast sand beach, of which about 77 miles is backed by dunes (U.S.
    Army Corps of Engineers 1971). Although sand beaches may be used by
    a large number of species, they are most important to the Snowy
    Plover, Willet, Whimbrel, and Sanderling. The Snowy Plover nests on
    the upper beach and forages on invertebrates on the upper and lower
    beach. Barren to sparsely vegetated sand dunes, which back some
    beaches, are also important Snowy Plover nesting and foraging areas
    (Page et al. 1995b). Migrating and wintering Black-bellied Plovers,
    Semipalmated Plovers, Willets, Whimbrels, Sanderlings, and other
    shorebirds forage on beaches and roost on the higher portions of the
    beach (Colwell and Sundeen in press) or in barren to
    sparsely-vegetated dunes backing beaches, particularly at high
    tides.

    Shorebirds foraging and roosting on coastal beaches experience
    considerable disturbance from humans. Birds are flushed by
    off-road-vehicle drivers, especially in Del Norte and Humboldt
    counties, and by pedestrians and joggers, particularly those with
    dogs, in all counties. Leash laws are seldom enforced so that dogs
    are permitted to chase roosting and foraging shorebirds. With the
    growing human population in California this type of disturbance
    undoubtedly will increase. Oil spills are another problem shorebirds
    experience on sand beaches. Shorebirds were oiled on Humboldt Bay
    and Point Reyes beaches during separate spills in November 1997 and
    on Point Reyes beaches during a January 1998 spill (PRBO unpubl.
    data).

    Nesting Snowy Plovers face numerous threats on sand beaches. These
    include loss of dune habitat to the introduced European beachgrass
    *(Ammophila arenaria),* decreased nesting success from human
    disturbance, and high levels of egg predation by Common Ravens.

    Priority conservation actions for sand beaches and dunes are to:

-   Increase the size of the breeding Snowy Plover population following
    the detailed guidelines of the draft Snowy Plover Recovery Plan.
    These include removing non-native vegetation in coastal dunes,
    restricting human recreation on sand beaches, using nest exclosures,
    and implementing predator management and public education programs.
    The draft Snowy Plover Recovery Plan lists site-specific actions,
    which should be endorsed by the shorebird conservation plan.

-   Increase enforcement of dog leash laws on beaches used by nesting
    Snowy Plovers and other feeding and roosting shorebirds.

-   Rank beaches by their importance to shorebirds; restrict dogs from
    those with highest ranks (Colwell and Sundeen in press).

-   Restrict off-road vehicle driving on Snowy Plover nesting beaches.

-   Restrict nighttime driving on beaches used by foraging and roosting
    shorebirds.

-   Limit human use of Brazil Beach, Tomales Bay, to protect large
    flocks of roosting shorebirds.

-   Limit human use of the outer beach at Sand Point, Tomales Bay, to
    protect roosting and feeding Snowy Plovers and potentially produce
    conditions conducive to nesting.

    *Rocky Shoreline.* There are about 249 miles of rocky coast
    shoreline in the Northern California Coast Subregion (U.S. Army
    Corps of Engineers 1971). Resident Black Oystercatchers use this
    habitat as their primary nesting, foraging, and roosting areas.
    During winter, the rocky shoreline of the region is the primary
    habitat of the Black Turnstone, which also forages on tidal flats.
    Other rocky coast species, occurring in small numbers in migration
    and winter are the Wandering Tattler, Spotted Sandpiper, Ruddy
    Turnstone, Surfbird, and Rock Sandpiper. Oil spills are the main
    threat to the species using this habitat.

    A priority conservation action for rocky shorelines is to:

-   Limit human access to Black Oystercatcher breeding sites.

    *Offshore Waters.* Offshore waters are important for migrating
    Red-necked and, particularly, Red phalaropes. Available food
    supplies in these waters are undoubtedly affected by ocean
    temperatures and large scale oceanic events such as El Niño
    conditions. The Red Phalarope may be affected by winter storms,
    which sometimes cause large numbers to come ashore in a weakened
    condition that leaves them susceptible to predators. Oil spills are
    the main human-induced problem for phalaropes in offshore waters.

    A priority conservation action for offshore waters is to:

-   Promote regulations reducing the probability of oil spills.

    *Agricultural Lands and Seasonal Wetlands.* Heavily grazed pastures
    -- especially at Humboldt Bay, Tomales Bay, Drakes Estero, and
    Bolinas Lagoon -- are important foraging and roosting sites for
    shorebirds when winter high tides inundate tidal flat foraging
    areas. Tilled land also is used in the Point Reyes area by some
    shorebirds, such as the Black-bellied Plover, Semipalmated Plover,
    and Killdeer. At Humboldt Bay, the California Department of Fish and
    Game (CDFG) and U.S. Fish and Wildlife Service (USFWS) rely on
    livestock grazing to manage pasture vegetation height to promote use
    by shorebirds and waterfowl (M. Colwell pers. comm.). Livestock
    grazing of flat land near coastal estuaries should be viewed as
    beneficial to shorebirds as long as the grazing does not contribute
    to increased sedimentation of intertidal habitats or impact
    sensitive species. In the Arcata Bottoms at Humboldt Bay,
    pastureland created by diking of salt marsh, interdigitating with
    alder and spruce forest, may now provide more habitat for wintering
    shorebirds than former salt marsh (M. Colwell pers. comm.).

####### Priority conservation actions for agricultural lands and seasonal wetlands are to: {#priority-conservation-actions-for-agricultural-lands-and-seasonal-wetlands-are-to .unnumbered}

-   Promote conservation easements to protect seasonal wetlands for
    shorebirds.

-   Protect seasonal wetlands and pastures from development at the Eel
    River lowlands, Humboldt Bay.

-   Protect seasonal wetlands in grazed lowlands east of Tomales at
    Tomales Bay.

-   Limit recreational use and restore seasonal wetlands at pastures at
    Lawson's Landing, Tomales Bay.

    **Monitoring Priorities**

    Priorities for monitoring shorebirds on the northern California
    coast are to:

-   Annually monitor shorebirds in coastal wetlands for long-term trends
    in abundance. The monitoring program should be standardized,
    thorough, and recognize changing habitat conditions. Prioritization
    of sites for monitoring should be based on all available
    information, ease of implementation, and level of bird use.
    Establish a network of organizations to undertake monitoring
    activities.

-   Annually monitor breeding numbers and nesting success of the Snowy
    Plover throughout the subregion.

-   Annually monitor shorebird foraging and roosting habitat
    availability and condition, including the level of human
    disturbance.

-   Annually monitor the presence and abundance of key shorebird
    predators -- especially the Merlin, Peregrine Falcon, and
    Short-eared Owl -- at key wintering sites.

    **Research Priorities**

    Priority research goals for the northern California coast are to:

-   Study the effects on shorebirds of off-road driving on beaches, use
    of personal water craft in wetlands, and pedestrian and pet use of
    beaches. In particular, determine how disturbances affect shorebird
    prey ingestion rates, energy budgets, body condition, and survival
    rates.

-   Determine the costs and benefits to foraging shorebirds of different
    oyster culture methods (for example bottom seeding versus
    long-lining), including the effects on shorebird prey ingestion
    rates and on sedimentation rates of tidal flats.

-   Examine the threats posed to nesting Black Oystercatchers by human
    disturbances and by predators such as the Common Raven.

-   Survey all rocky shoreline in the region to determine the most
    important areas for migrant and wintering shorebirds.

-   Investigate why shorebirds consistently use some pastures at
    Humboldt Bay for foraging more than others.

-   Determine the effect of bait digging and claming on shorebirds and
    their invertebrate prey at Bodega Harbor.

-   Delineate shorebird breeding areas, especially for the Red Knot,
    which winters and migrates along the coast.

-   Identify the wintering area(s) of the small population of Marbled
    Godwits that breeds in Alaska.

-   Determine site fidelity and survivorship of migrating and wintering
    shorebirds.

-   Increase understanding of stop-over ecology of migrant shorebirds.

    **Education Priorities**

    Priority education goals for the subregion are to:

-   Educate adults and children about the potential effect of their
    actions, or those of their pets, on nesting, feeding, or roosting
    shorebirds.

-   Develop programs to increase public appreciation of shorebirds,
    their migrations, and life styles.

    **Implementation and Coordination**

    The wetlands of the entire coastline are included in the Pacific
    Coast Joint Venture of the North American Waterfowl Plan. Given the
    collaboration of many agencies in the Pacific Coast Joint Venture,
    it is the best entity to coordinate the shorebird management issues
    for the Northern California Coast Subregion. The many agencies
    involved in the Joint Venture or that otherwise manage coastal
    habitats are:

    California Coastal Conservancy -- a state regulatory agency that
    also administers programs to improve the natural resources along the
    entire coastline.

    California Department of Fish and Game -- the primary agency
    managing wildlife on state lands; particularly active on the north
    coast at Lake Talawa, Humboldt Bay, and Tomales Bay.

    California Department of Parks and Recreation -- manages many of the
    sand beaches along the northern California coastline.

    Golden Gate Biosphere Reserve -- a collaborative effort of various
    agencies, including those with management interests at Point Reyes
    wetlands.

    Golden Gate National Recreation Area -- has management
    responsibilities at Bolinas Lagoon.

    Humboldt Bay Harbor District -- a group that proposes to balance
    conservation and development of bay habitats.

    Humboldt Bay Management Group -- focuses on management issues within
    Humboldt Bay.

    Marin County Open Space District -- manages resource protection and
    recreational activities at Bolinas Lagoon.

    National Oceanic and Atmospheric Administration -- through the Gulf
    of the Farallones Marine Sanctuary this agency has regulatory
    responsibilities at Estero Americano, Tomales Bay, Bolinas Lagoon,
    and adjacent offshore waters.

    Sonoma County -- manages bay-front parks at Bodega Harbor.

    U.S. Fish and Wildlife Service -- manages Humboldt Bay National
    Wildlife Refuge.

    U. S. National Park Service -- through the Point Reyes National
    Seashore (PRNS) manages Tomales Bay (in part), Abbotts Lagoon,
    Drakes Estero, and Limantour Estero. PRNS is facilitating
    development of a Tomales Bay User Plan with area stakeholders. It
    would be desirable if this plan would incorporate the
    recommendations for Tomales Bay included in the shorebird
    conservation plan.

    Various county park departments -- manage some coastal beaches.

    **SAN FRANCISCO BAY SUBREGION**

    **Description of Subregion**

    San Francisco Bay is about 516,600 acres in size. For purposes of
    this plan it is divided into Suisun Bay, North Bay (or San Pablo
    Bay), Central Bay, and South Bay. Information on historical and
    current amounts of habitat San Francisco Bay are taken from the
    Goals Project (1999).

    *Suisun Bay.* Prior to major human alteration, beginning about 200
    years ago, Suisun Bay consisted of 16,746 acres of deep bay, 24,095
    acres of shallow bay, 2,405 acres of tidal flat, 65,358 acres of
    tidal marsh, 2 acres of lagoons, and 2 acres of other baylands.
    Hundreds of small to large natural marsh ponds occurred in the
    western portion of the marsh. By the late 1990s, human alterations
    had reduced the area of deep bay 31% to 11,584 acres, shallow bay 7%
    to 22,428 acres, tidal flat 53% to 1,124 acres, and tidal marsh 79%
    to 13,562 acres. Replacement habitats include 49,873 acres of diked
    wetland, 5,544 acres of agricultural land, 720 acres of storage and
    treatment ponds, 762 acres of undeveloped bay fill, 2,453 acres of
    developed bay fill, and 570 acres of other bayland.

    Diking of Suisun Bay, primarily for livestock grazing, commenced
    about 1865. In the 1870s and 1880s the first duck clubs were
    established around the marsh ponds. By the early 1900s livestock
    grazing was giving way to other agricultural activities, such as the
    production of sugar beets, asparagus, lima beans, oats, and barley.
    Eventually increasing salinity and land subsidence caused
    agricultural activities to fail and be replaced by duck clubs in the
    eastern part of the bay. Currently, the only agricultural activity
    is some oat hay farming on 1,500 acres of former bayland. Levees
    originally constructed for farming are now an integral part of the
    infrastructure of the duck clubs. Suisun Marsh is now considered San
    Francisco Bay's largest contiguous protected area, consisting of
    89,000 acres of wetland, channels, and bays and 22,500 acres of
    adjacent uplands. Included are 49,873 acres of privately and
    publicly owned marsh managed primarily for duck hunting. Among the
    publicly owned areas are the state Grizzly and Joyce Island Wildlife
    Areas.

    *North Bay.* Historically, the composition of the North Bay was
    20,139 acres of deep bay, 55,120 acres of shallow bay, 13,351 acres
    of tidal flat, 55,076 acres of tidal marsh, 37 acres of lagoons, 270
    acres of salt pans, and 24 acres of other baylands. Since 1850 the
    acreage of deep bay has decreased 49% to 10,362 acres, shallow bay
    has remained about the same at 53,804 acres, tidal flat has
    decreased 32% to 9,118 acres, and tidal marsh has decreased 70% to
    16,347 acres. Lagoons have increased to 2,353 acres, salt ponds to
    7,143 acres, diked wetlands to 7,622 acres, agricultural baylands to
    27,732 acres, storage and treatment ponds to 1,266 acres,
    undeveloped bay fill to 1,648 acres, developed bay fill to 6,211
    acres, and other baylands to 565 acres.

    Tidal marshes in the North Bay were diked initially to create land
    for livestock grazing, which remained the sole agricultural practice
    in the region for many decades; high water tables and soil
    salinities discouraged other crops. In 1952, Leslie Salt Company
    expanded salt production into the North Bay by converting
    agricultural land into salt evaporation ponds. During recent
    decades, some of the remaining agricultural lands have been managed
    for the production of cattle silage and vineyards. In 1997, all the
    salt ponds, except the Napa crystallizer ponds, were sold to the
    California Department of Fish and Game, which now manages the ponds
    as a state Wildlife Area.

    *Central Bay.* The Central Bay historically consisted of 55,609
    acres of deep bay, 57,272 acres of shallow bay, 13,532 acres of
    tidal flat, 13,461 acres of tidal marsh, 45 acres of lagoons, and
    215 acres of other baylands. Deep bay (now at 53,614 acres) and
    shallow bay (53,774 acres) have decreased less than 10% from
    historic levels. In contrast, the area of tidal flat has decreased
    70% to 4,014 acres and tidal marsh 93% to 947 acres. Habitats that
    have replaced tidal flat and marsh include lagoons (now at 658
    acres), diked wetlands (1,314 acres), agricultural bayland (34
    acres), storage and treatment ponds (57 acres), undeveloped bay fill
    (3,420 acres), developed bay fill (21,970 acres), and other baylands
    (380 acres). Urban development now abuts much of the Central Bay
    shoreline.

    *South Bay.* Historically the South Bay had 7,035 acres of deep bay,
    37,955 acres of shallow bay, 21,181 acres of tidal flat, 56,037
    acres of tidal marsh, 1,316 acres of salt pans, 12 acres of
    undeveloped bay fill, and 13 acres of other baylands. The amount of
    deep bay has changed little during the past 200 years and today is
    estimated at 6,851 acres. Shallow bay has increased by 10% to 41,812
    acres but tidal flat has declined by 29% to 14,955 acres and tidal
    marsh by 83% to 9,335 acres. Other habitats that have increased or
    were not present historically are lagoons (598 acres), commercial
    salt ponds (27,313 acres), other baylands (347 acres), diked bayland
    (5,709 acres), agricultural land (1,309 acres), storage and
    treatment ponds (1,628 acres), undeveloped bay fill (1,768 acres),
    and developed bay fill (11, 930 acres). Alteration of wetlands for
    urban development and salt production are the two most prominent
    causes of habitat change in the South Bay.

    **Shorebird Species**

    Overall, San Francisco Bay holds higher proportions of the region's
    total wintering and migrating shorebirds than any other coastal
    wetland within the U.S. Pacific coast wetland system (Table 1).

  ---------------------- ---------------- ---------------- ----------------
  **Table 1** Percent of                                   
  coastal shorebird                                        
  totals found in San                                      
  Francisco Bay on PRBO                                    
  surveys of all the                                       
  major wetlands of the                                    
  contiguous U. S.                                         
  Pacific coast (from                                      
  Page et al. 1999).                                       

                                                           

                                                           

                         Season                            

                                                           

  Species                Fall             Winter           Spring

                                                           

  Black-bellied Plover   62               59               55

  Semipalmated Plover    52               40               47

  Black-necked Stilt     78               90               58

  American Avocet        96               88               86

  Greater Yellowlegs     41               41               26

  Willet                 69               58               57

  Long-billed Curlew     66               49               46

  Marbled Godwit         62               46               68

  Red Knot               76               43               39

  Western Sandpiper      59               68               54

  Least Sandpiper        67               39               73

  Dunlin                 \-               38               24

  dowitcher spp.         72               65               49

                                                           
  ---------------------- ---------------- ---------------- ----------------

San Francisco Bay is the northernmost regular breeding area of the
American Avocet and Black-necked Stilt on the U.S. Pacific coast. About
10% of the U.S. Pacific coast population of the Snowy Plover breeds in
South Bay salt ponds. San Francisco Bay is recognized as a WHSRN site of
Hemispheric Importance for shorebirds -- the highest possible ranking.

**Regional Population and Habitat Goals**

Priority population and habitat conservation goals for San Francisco Bay
are to:

-   Attain a breeding population of 500 Snowy Plovers, consistent with
    the population objectives of the draft Snowy Plover Recovery Plan.

-   Maintain or increase current breeding populations of the Killdeer,
    Black-necked Stilt, and American Avocet.

-   Maintain or increase current populations of migrating and wintering
    shorebirds.

-   Restore 4,000 acres of tidal flat habitat throughout the bay.

-   Protect existing tidal flat habitat from introduced plants and
    invertebrates.

-   Protect existing habitat from further fragmentation by human-created
    infrastructures such as power lines.

-   Acquire and manage artificial salt ponds specifically for
    shorebirds.

-   Implement wetland management practices favorable to breeding,
    wintering, and migrating shorebirds.

    **Habitat Status, Threats, and Management Needs**

    Descriptions of historical and current habitat availability,
    shorebird habitat use patterns, threats to shorebirds, management
    issues, and needed conservation actions are provided below for the
    major habitat types in the San Francisco Bay estuary.

    *Tidal Flats.* Currently there are about 29,212 acres of tidal flat
    in San Francisco Bay, a 42% decrease from the historical level of
    50,469 acres. Today about 90% of the tidal flats occur on the bay's
    edges and about 10% along marsh channels. Historically, a greater
    proportion of the tidal flat occurred along marsh channels. Tidal
    flats are the principal foraging area for most shorebirds in San
    Francisco Bay at low tide. Species that forage on tidal flats
    include the Black-bellied Plover, Semipalmated Plover, Willet,
    Long-billed Curlew, Marbled Godwit, Red Knot, Dunlin, Western
    Sandpiper, Least Sandpiper, Short-billed Dowitcher, and Long-billed
    Dowitcher. Tidal flat invertebrates are the primary shorebird food,
    but the majority of these have been introduced by man.

    Within the past decade, salt-water cord grass (*Spartina
    alterniflora)* has been introduced into the bay from stock
    originating on the Atlantic coast of the U.S. This species grows at
    both lower and higher elevations in the intertidal zone than the
    native California cord grass (*Spartina foliosa)* and thereby
    threatens to reduce the amount of unvegetated tidal flat available
    to foraging shorebirds. The USFWS, East Bay Regional Park District,
    CDFG, and others have ongoing management programs using physical and
    chemical methods to control and eliminate *Spartina alterniflora*.

    Other factors impacting, or potentially impacting, tidal flats and
    the invertebrates living in them include sea level rise,
    contaminants, oil spills, and proposed new ferry systems. Sea level
    rise, projected from current levels of global warming, is a
    phenomena that could greatly alter the acreage of tidal flat in the
    bay. Some communities, such as Corte Madera, currently are proposing
    to construct tidal barriers on tidal flats to prevent future
    flooding of urban areas from sea level rise. Contaminants, such as
    selenium and mercury, are widespread in bay sediments. There is a
    high potential for oil spills, which could have a major impact on
    shorebirds and their food supply. Proposed new ferry transport
    systems may involve the use of hover craft over tidal flats, where
    their high noise levels and frequent presence has the potential to
    disturb foraging shorebirds or their benthic invertebrate prey.
    Dredging to accommodate ferry facilities also could reduce the
    amount of available intertidal habitat.

    Priority conservation actions for tidal flat habitat are to:

-   Increase the extent of tidal flat by adding 4,000 acres throughout
    the bay.

-   Eliminate non-native vegetation (e.g., *Spartina alterniflora)* that
    threatens tidal flats.

-   Develop regulations to reduce invasions of non-native benthic
    invertebrates.

-   Oppose human activities that increase disturbance to shorebirds.

    *Salt Ponds.* Historically, about 1,594 acres of natural salt pans
    occurred in the tidal marsh of the North and South bays. Most of
    this habitat was located in the South Bay, primarily near Hayward at
    San Lorenzo Creek and Mount Eden Slough. The largest pond complex,
    Crystal Pond, extended over some 1,000 acres. As the demand for salt
    rose in the mid-1800s, the first artificial salt ponds were
    developed as extensions and improvements of the natural salt ponds.
    Subsequently, artificial salt ponds have entirely displaced their
    natural forerunners. Currently there are 34,455 acres of salt ponds
    in the bay; the majority were constructed on former salt marsh.

    Salt ponds are the principal foraging habitat (south of Suisun Bay)
    of the Black-necked Stilt, Wilson's Phalarope, and Red-necked
    Phalarope. The large increase in acreage of salt ponds during the
    past 200 years likely has augmented numbers of these species in the
    bay over historical levels. On PRBO shorebird surveys of the North,
    Central, and South bays, the median proportions of Black-necked
    Stilts found in the salt ponds, versus other habitats, were 86% and
    60% for fall and spring, respectively. For the Red-necked Phalarope,
    comparable proportions were 99% and 93% (PRBO unpubl. data). The
    American Avocet and Snowy Plover are species that use both salt
    ponds and tidal flats for foraging and now likely are more abundant
    in the bay than formerly. Other species that feed principally on
    tidal flats at low tide, such as the Dunlin, Western Sandpiper,
    Least Sandpiper, and Willet, also forage in the salt ponds at high
    tide. Most shorebirds use the salt ponds, especially the levees and
    islands, as high tide roosting areas.

    Dry margins and levees of salt ponds are the chief nesting habitat
    of the Snowy Plover in San Francisco Bay and also are important
    nesting areas for the Black-necked Stilt and American Avocet. None
    of these species may have nested in the bay prior to the development
    of the salt ponds. The Snowy Plover was known to nest in the bay at
    salt ponds by 1918, whereas the American Avocet and Black-necked
    Stilts were first known to breed there in 1926 and 1927,
    respectively (Harvey et al. 1992).

    In the last two decades, shorebirds nesting in the salt ponds have
    been impacted by introduced mammalian predators and expanding
    populations of native predators. Feral red foxes have been
    identified as important predators of plover, avocet, and stilt
    clutches; feral and free-roaming cats also may be a problem. Common
    Ravens -- important predators of the eggs of nesting shorebirds --
    are expanding their breeding range into the bay, where they nest on
    power line towers and other artificial structures.

    Conversion of salt ponds to tidal marsh is a widely supported
    concept to increase habitat for several threatened and endangered
    marsh species in the bay. A resulting decrease in salt pond habitat
    could reduce numbers of some shorebird species, especially the Snowy
    Plover, Black-necked Stilt, American Avocet, Wilson's Phalarope, and
    Red-necked Phalarope.

    Priority conservation actions for salt ponds are to:

-   Acquire and manage 10,000 acres of salt ponds specifically for
    nesting, feeding, and roosting shorebirds. Of these, 2,000 acres
    should be managed specifically for nesting Snowy Plovers, as
    recommended in the draft Snowy Plover Recovery Plan.

-   Use fencing and exclosures to protect Snowy Plover nests from egg
    predators.

-   Maintain public closures of Snowy Plover nesting areas during the
    breeding season on Don Edwards National Wildlife Refuge, Baumberg
    Eden Landing Ecological Reserve, and Hayward Area Regional Park
    District lands.

-   Continue to manage non-native and native mammalian predators to
    limit predation of the eggs and chicks of the Snowy Plover and other
    nesting shorebirds in all important nesting habitat. Predator
    management by a number of public and private landowners is an
    ongoing cooperative activity to protect nesting California Clapper
    Rails, Snowy Plovers, and other migratory birds.

-   Develop and implement a strategy to manage avian predators of
    shorebird eggs and chicks.

-   Develop methods to prevent the spread of vegetation in dry salt
    ponds.

-   Determine salt pond salinities most beneficial to shorebirds.

    *Managed Diked Marsh.* Diked wetlands are a human-created habitat
    currently totaling about 64,518 acres in the bay. Of these, 77% are
    in Suisun Bay, 11% in North Bay, 2% in Central Bay, and 9% in South
    Bay. Diked wetlands make up about 67% of all bayland habitat in
    Suisun Bay. The Suisun Bay diked wetlands, which are privately and
    publicly owned, are managed primarily for waterfowl hunting. These
    wetlands provide important foraging habitat for the Black-necked
    Stilt, American Avocet, Greater Yellowlegs, Dunlin, and Long-billed
    Dowitcher and nesting habitat for the Killdeer, Black-necked Stilt,
    and American Avocet. Diked wetlands, whether duck ponds or abandoned
    salt evaporation ponds, vary considerably in water level, salinity,
    and amount and type of vegetation. Consequently, shorebird use can
    be highly variable among ponds.

    Priority conservation actions for managed diked marshes are to:

-   Time water drawdowns in managed marshes of Suisun Bay to correspond
    with the peak of spring shorebird migration from mid-April to
    mid-May. Manage vegetation in some marsh cells to provide broad
    expanses of open habitat.

-   Create 1-6 inch water depths in some Suisun Marsh managed ponds for
    wintering shorebirds.

-   Increase nesting habitat for the Black-necked Stilt and American
    Avocet in Suisun Bay managed marshes through the strategic placement
    of islands.

    *Salt Marsh.* There currently are about 40,191 acres of tidal marsh
    in the bay, a 79% decline from historic levels. Tidal marsh has been
    lost primarily to the development of salt ponds, agriculture land,
    and urban areas. Marsh channels, ponds, and wrack are used by many
    species of shorebirds for foraging, whereas vegetated portions of
    marsh are relatively little used. Species most likely to be found
    foraging in marshes are the Willet and Least Sandpiper. Black-necked
    Stilts nest in marshes with shallow ponds.

    Priority conservation actions for tidal marsh are to:

-   Include channels in the design of tidal marsh restoration projects.

-   Create shallow ponds in marshes for nesting Black-necked Stilts.

-   Increase tidal circulation in marshes to enhance invertebrate
    productivity and shorebird foraging areas.

    *Agricultural Baylands.* Currently there are about 34,620 acres of
    agricultural baylands of which about 80% are located in the North
    Bay. Seasonal wetlands that form on these agricultural lands after
    winter rains are foraging habitat for many shorebirds, such as the
    Greater Yellowlegs, Western Sandpiper, Least Sandpiper, Dunlin, and
    Long-billed Dowitcher.

    *All Habitats.* A priority conservation action for all habitats is
    to:

-   Oppose the addition of any more power lines and support the
    rerouting of existing ones away from bay habitat.

    **Monitoring Priorities**

    Priority monitoring needs for the San Francisco Bay estuary are to:

-   Devise and implement a method to annually monitor trends in
    shorebird abundance in San Francisco Bay.

-   Conduct annual surveys of Snowy Plover nesting distribution and
    abundance.

    **Research Priorities**

    Priority research needs for the San Francisco Bay estuary are to:

-   Identify the salinities, water depths, and physical features of salt
    ponds most valuable to shorebirds.

-   Investigate how to manage salt ponds for shorebirds in the absence
    of commercial salt production.

-   Determine how to replace salt ponds as shorebird roosting sites
    before undertaking the conversion of pond habitat to marsh habitat.

-   Quantify shorebird use of non-fully tidal wetlands, such as muted
    tidal wetlands, seasonal wetlands, and abandoned salt ponds.

-   Measure Snowy Plover reproductive success, survival, habitat
    selection, and site fidelity within the bay.

-   Determine the current abundance and distribution of nesting
    Black-necked Stilts and American Avocets within the bay.

-   Inventory shorebird numbers in Suisun Bay.

-   Quantify the nesting habitat requirements of the Black-necked Stilt
    and American Avocet in Suisun Marsh.

-   Identify the characteristics of the most productive nesting islands
    for Black-necked Stilts.

-   Determine water depths of Suisun Bay managed marshes most beneficial
    to shorebirds.

-   Delineate how vegetation and water depth should be managed in
    seasonal wetlands to benefit shorebirds.

-   Quantify the benefits shorebirds gain from restoration projects.

-   Determine the effect that bayside trail use, kayaking, and other
    human recreational activities have on shorebirds.

-   Investigate the effects of introduced invertebrate prey on shorebird
    foraging ecology.

### Education Priorities {#education-priorities .unnumbered}

Education priorities for the subregion are to:

-   Support existing education, outreach, and interpretive programs at
    all sites.

-   Initiate focused shorebird conservation and education programs.

-   Disseminate information on research-driven adaptive management
    techniques.

    **Implementation and Coordination**

    Because of large reductions in tidal marsh and tidal flat in San
    Francisco Bay, some endemic marsh subspecies have declined in
    abundance and have been federally listed as endangered (e.g.,
    California Clapper Rail and salt marsh harvest mouse). There is an
    urgent need to increase the amount of marsh habitat for these
    species and consequently much attention is focused on marsh
    restoration. Since space and opportunities for habitat restoration
    are finite, there is a need to look at the habitat requirements of
    all species to develop a comprehensive conservation plan for the
    wildlife of San Francisco Bay. Accordingly, from 1995 to 1999
    scientists and resources managers familiar with the San Francisco
    Bay ecosystem worked together on the San Francisco Bay Area Wetland
    Ecosystem Goals Project to produce a blueprint for the kinds,
    amounts, and distribution of wetland habitats needed in the estuary
    to sustain diverse and healthy wildlife communities. The results of
    this planning effort are outlined in the Bay Ecosystem Habitat Goals
    Report (Goals Project 1999). Although the habitat recommendations in
    the report are voluntary, they are likely to help guide the efforts
    of several groups involved in habitat acquisition, restoration, and
    enhancement in the estuary. These groups include:

    CALFED -- a collaborative effort of state and federal agencies and
    urban, agricultural, and environmental interest groups to address
    the environmental and water management problems of the San Francisco
    Bay-Delta system. CALFED is developing a long-term comprehensive
    plan for restoring the ecological health of the bay and delta and
    for improving water management. Within CALFED, the Ecosystem
    Restoration Program's stated objectives include increasing and
    improving aquatic and terrestrial habitats, improving the ecological
    functioning of the bay-delta system, and increasing the ability of
    the system to support sustainable populations of diverse plant and
    animal species. CALFED is a source of funding for restoration and
    enhancement projects, especially in Suisun Bay and North Bay.

    California Coastal Conservancy -- a state agency that administers
    programs to improve natural resources along the California
    coastline. In 1997 the Conservancy initiated its San Francisco Bay
    Area Conservancy Program in an effort to identify and adopt
    long-term goals for resource protection and recreation in the nine
    counties surrounding the bay. The California Coastal Conservancy
    undertakes acquisition projects and awards grants for restoration
    projects.

    California Department of Water Resources -- this state agency has
    developed the Plan of Protection for the Suisun Marsh in recognition
    of the wildlife values of the managed and tidal marshes.

    San Francisco Bay Conservation and Development Commission (BCDC) --
    BCDC has developed the San Francisco Bay Plan for the conservation
    of San Francisco Bay waters and the regulation of shoreline
    development. In 1999, the Commission will commence a five-year
    process to update the plan. It is expected to use information from
    the Goals Project for revising its sections on bay habitats and
    wildlife. BCDC also developed the Suisun Marsh Protection Plan and
    Act, which the Legislature ratified in 1997. This plan, which has
    wide support among private landowners and public agencies, decrees
    that when feasible historic marshes should be returned to either
    managed or tidal wetland status and that if managed wetlands are not
    needed for waterfowl hunting they should be restored to tidal
    marshes.

    San Francisco Bay Joint Venture -- this public and private
    partnership was formed in 1996 to promote the acquisition,
    restoration, and enhancement of bay area wetlands and associated
    habitats. Operating under the North American Waterfowl Management
    Plan, this Joint Venture is currently preparing an implementation
    strategy for habitat acquisition, restoration, and enhancement using
    the Goals Project. The Joint Venture has identified about 40 pending
    or proposed restoration projects that could benefit shorebirds in
    the bay.

    Suisun Resource Conservation District -- this agency has been
    working since the 1960s to encourage private landowners to manage
    lands more effectively.

    U.S. Fish and Wildlife Service -- USFWS is aiding conservation of
    bay habitats through its Recovery Plan for Tidal Marsh Ecosystems of
    Central and Northern California and the Recovery Plan for the
    Western Snowy Plover, Pacific Coast Population.

    It would be appropriate for the San Francisco Bay Joint Venture to
    take the lead role in implementing the shorebird conservation plan
    in San Francisco Bay.

    **SOUTHERN CALIFORNIA COAST SUBREGION**

### Description of Subregion {#description-of-subregion .unnumbered}

The Southern California Coast Subregion encompasses about 648 miles of
coastline of which 59% is sand beach, 38% rocky shoreline, and 2% gravel
or cobble beach (U.S. Army Corps of Engineers 1971). Dozens of wetlands
are interspersed along the coastline.

**Wetlands of Importance to Shorebirds**

We identified 25 wetlands along the southern California coast that are
used by hundreds to ten of thousands of shorebirds. Shorebirds numbers
attributed to each of the 25 wetlands below are from unpublished data of
Point Reyes Bird Observatory (PRBO) unless otherwise indicated.

*Santa Cruz County*

Pajaro River Mouth -- holds up to 1,800 shorebirds.

*Monterey County*

Elkhorn Slough -- holds over 30,000 shorebirds in fall and winter; a
potential WHSRN site of Regional Importance. See also Ramer et al.
(1991).

Salinas River Mouth -- holds up to 1,000 shorebirds in fall and spring.

*San Luis Obispo County*

Morro Bay -- holds up to 20,000 shorebirds in winter; a potential WHSRN
site of Regional Importance.

Santa Maria River Mouth -- holds hundreds of shorebirds.

######## Santa Barbara County {#santa-barbara-county .unnumbered}

Devereaux Slough -- holds hundreds of shorebirds.

Goleta Slough -- occasionally holds just over a hundred shorebirds.

*Ventura County*

Mugu Lagoon -- holds up to 66,000 shorebirds during spring and over
10,000 at times in fall and winter; a potential WHSRN site of Regional
and possibly International Importance.

*Los Angeles County*

Malibu Lagoon -- holds hundreds of shorebirds.

Los Angeles River Mouth -- holds up to 5,800 shorebirds in fall.

San Gabriel River Mouth -- holds hundreds of shorebirds.

######## Orange County {#orange-county .unnumbered}

Seal Beach NWR -- holds up to 5,500 shorebirds in winter; recognized as
a wetland of International Importance by the Ramsar Convention Treaty.

Bolsa Chica -- holds up to 5,400 shorebirds in fall, 7,000 in winter,
and 7,700 in spring.

Santa Ana River Mouth -- holds hundreds of shorebirds (L. Hays pers.
comm.).

Upper Newport Bay -- holds up to 5,800 shorebirds in fall, 14,800 in
winter, and 8,800 in spring; a potential WHSRN site of Regional
Importance.

San Joaquin Marsh -- holds hundreds of shorebirds (L. Hays pers. comm.).

######## San Diego County {#san-diego-county .unnumbered}

Santa Margarita River Mouth -- holds up to 1,600 shorebirds in fall and
hundreds in winter and spring.

Agua Hedionda Lagoon -- holds hundreds of shorebirds.

Batiquitos Lagoon -- holds up to 1,000 to 2,000 shorebirds at all
seasons.

San Elijo Lagoon -- holds up to 3,500 shorebirds in fall and 1,500 in
spring. See also King et al. (1987).

San Dieguito Lagoon -- holds hundreds of shorebirds.

Los Penasquitos Lagoon -- holds hundreds of shorebirds.

Mission Bay/San Diego Flood Control Channel -- holds up to 5,000 to
6,000 shorebirds depending on season.

San Diego Bay -- holds up to 18,000 shorebirds in fall, 11,000 in
winter, and 13,000 in spring; recognized as a WHSRN site of Regional
Importance. See also Terp (1998).

Tijuana River Estuary -- holds up to 1,000 to 2,000 shorebirds at all
seasons.

**Beaches of Importance to Shorebirds**

Over half the southern California shoreline is sand beach, an important
habitat for the Snowy Plover year round and for other species during
migration and winter. Monterey Bay beaches support thousands of
shorebirds during migration and winter; principal species include the
Black-bellied Plover, Snowy Plover, Willet, Whimbrel, Marbled Godwit,
and Sanderling (PRBO unpubl. data). Beaches in the vicinity of coastal
wetlands, such Morro Bay and Mugu Lagoon, also are used by thousands of
roosting shorebirds at high tide. Beaches identified as important to
nesting or wintering Snowy Plovers in the draft Snowy Plover Recovery
Plan also are likely the main beaches used by other shorebirds.

Specific beaches identified as being particularly important to
shorebirds, listed north to south by county, are:

San Francisco County -- Ocean Beach.

San Mateo County -- Pacifica Beach, Half Moon Bay beaches, Tunitas
Creek, San Gregorio Creek, Pomponia Creek, Pescadero Creek, Gazos Creek,
and Año Nuevo beaches.

Santa Cruz County -- Waddell Creek, Scott Creek, Laguna Creek, Baldwin
Creek, Wilder Ranch, and the extensive Monterey Bay beach from Santa
Cruz to the Pajaro River mouth.

Monterey County -- extensive beach along Monterey Bay from the Pajaro
River mouth to Monterey, Asilomar Beach, Carmel River, and Point Sur
Beach.

San Luis Obispo County -- San Carpoforio Creek, Arroyo Hondo Creek,
Point Sierra Nevada, Arroyo de la Cruz, Sidneys Lagoon, Piedras Blancas,
Arroyo Laguna Creek, Pico Creek, San Simeon Beach, Villa Creek, Toro
Creek, Atascadero Beach, Morro Bay sand spit, Avila Beach, and the long
beach from Pismo Beach to the Santa Maria River mouth.

Santa Barbara County -- beach from Santa Maria River mouth to Point Sal,
Vandenberg Air Force Base beaches including Santa Ynez River mouth,
Jalama Beach, Hollister Ranch beaches, Devereaux Slough Beach, Goleta
Beach, Santa Barbara Harbor beaches, Carpinteria Beach, and the beaches
of San Miguel, Santa Rosa, and Santa Cruz islands.

Ventura County -- San Buena Ventura Beach, beach from Mandalay Bay to
Santa Clara River mouth, Hollywood Beach, Ormond Beach, Mugu Lagoon
Beach, and beaches of San Nicolas Island.

Los Angeles County -- Zuma Beach, Corral Beach, Malibu Lagoon Beach,
Santa Monica Beach, Dockwiller to Hermosa beaches, and the beaches of
San Clemente Island.

Orange County -- Huntington Beach, Newport Beach, Crystal Cove, Salt
Creek, Doheny Beach, and San Onfre Beach (part).

San Diego County -- San Onfre Beach (part), Aliso Creek, French Creek,
Santa Margarita River, San Luis Rey River, Agua Hedionda Lagoon, South
Carlsbad Beach, Batiquitos Lagoon, San Elijo Lagoon, San Dieguito
Lagoon, Los Penasquitos Lagoon, South Mission Beach, Ocean Beach, Silver
Strand, and Tijuana River Estuary.

**Shorebird Species**

The Southern California Coast Subregion is an important wintering area
for many shorebird species, such as the Black-bellied Plover, Willet,
Long-billed Curlew, Marbled Godwit, Red Knot, Western Sandpiper, Least
Sandpiper, Dunlin, Short-billed Dowitcher, and Long-billed Dowitcher. It
also is an important migration staging area, especially for the
Whimbrel, Western Sandpiper, Short-billed Dowitcher, Wilson's Phalarope,
and Red-necked Phalarope. Black-necked Stilts and American Avocets nest
in some of the wetlands and Black Oystercatchers on the rocky shoreline.
Over two thirds of the listed Snowy Plover population breeds at the
beaches and wetlands in the subregion.

**Regional Population and Habitat Goals**

######### Priority population and habitat goals for the southern California coast are to: {#priority-population-and-habitat-goals-for-the-southern-california-coast-are-to .unnumbered}

-   Attain and maintain a breeding population of 2,040 Snowy Plovers
    following the management recommendations of the draft Snowy Plover
    Recovery Plan.

-   Maintain or increase current breeding populations of the Killdeer,
    Black Oystercatcher, Black-necked Stilt, and American Avocet.

-   Increase numbers of wintering and migrating shorebirds by increasing
    and improving habitat, particularly by offsetting historic wetland
    loss by restoring tidal flat and salt marsh habitat.

-   Maintain or increase the current amount and distribution of
    shorebird nesting habitat.

-   Reduce erosion of sediment from watersheds into lagoon and estuarine
    habitats.

-   Prevent further introductions of non-native invertebrates into the
    benthos.

-   Eliminate non-native plants that degrade shorebird habitat (e.g.,
    *Ammophila arenaria* from Snowy Plover nesting areas).

-   Prevent further building of roads, power lines, and other human
    structures on or above wetlands.

-   Direct human activities away from nesting, foraging, and roosting
    areas of the Snowy Plover and other shorebirds.

-   Haze shorebirds away from areas containing hazardous levels of
    environmental contaminants in invertebrates or substrates until the
    hazardous materials are removed.

    **Habitat Status, Threats, and Management Needs**

    Descriptions of historical and current habitat availability,
    shorebird habitat use patterns, threats to shorebirds, management
    issues, and needed conservation actions are provided below for the
    major wetland areas on the southern California coast..

    *Pajaro River Mouth*. The Pajaro River Mouth and connecting
    Watsonville Slough are bordered by a residential development,
    agricultural fields, and Zmudowski State Beach. Although the river
    mouth is often open to tidal action for extended periods, especially
    in winter, it must be opened when it closes to prevent nearby
    agricultural fields from flooding. The beach is a Snowy Plover
    nesting area. Small numbers of the American Avocet and Black-necked
    Stilt periodically nest along Watsonville Slough. The beach and
    river flats provide valuable foraging and roosting habitat for a
    wide variety of migrating and wintering shorebirds, including the
    Black-bellied Plover, Willet, Marbled Godwit, Sanderling, and
    Western Sandpiper. Known or potential impacts to shorebirds here
    include human disturbance of nesting Snowy Plovers and other
    shorebirds feeding or roosting on the beach, colonization of the
    beach by *Ammophila arenaria*, predation of Snowy Plover eggs by
    feral red fox, predation of Snowy Plover chicks by Loggerhead
    Shrikes, and possibly poor water quality from agricultural run-off.
    The California Department of Parks and Recreation (CDPR) manages the
    beach for nesting Snowy Plovers by closing areas and erecting
    exclosures to protect nests from humans and egg predators. CDPR has
    also commenced an *Ammophila* eradication program to increase Snowy
    Plover nesting habitat (G. Page pers. obs.).

    *Elkhorn Slough.* In the approximately 4,000-acre Elkhorn Slough and
    associated wetlands, tidal mudflat is the primary feeding area for
    most shorebirds. An extensive *Salicornia* marsh is also used for
    foraging and roosting by the Marbled Godwit, Willet, Long-billed
    Curlew and Least Sandpiper, particularly at high tide.
    Tidally-restricted mudflat occurs in North Marsh and Moro Cojo
    Slough. Although tidal flow into Moro Cojo Slough is restricted by
    culverts, creating an area where water fluctuations are governed by
    rainfall and evaporation, the slough is used as a high tide foraging
    and roosting area by many shorebirds, a foraging area for the
    Black-necked Stilt and American Avocet on all tides, and a nesting
    area for the Black-necked Stilt, American Avocet and Killdeer. At
    the upper end of Elkhorn Slough, Black-necked Stilts also nest in
    the diked Porter Marsh, which is cut off from tidal influence; tide
    gates prevent water from entering but not exiting into the main
    channel of Elkhorn Slough. North and Strawberry marshes are managed
    for flood and mosquito control but provide important foraging
    habitat for the American Avocet, Black-necked Stilt, and dowitchers.
    Strawberry Marsh provides foraging habitat for the Red-necked
    Phalarope in fall. Former salt ponds are now managed by CDFG as the
    Moss Landing Wildlife Area. The ponds support nesting Snowy Plovers,
    Black-necked Stilts, and American Avocets during summer and many
    other shorebirds at other seasons. Sand beach at Elkhorn Slough
    mouth is foraging and roosting habitat for several shorebird species
    and nesting habitat for the Snowy Plover. Issues relevant to
    shorebirds at Elkhorn Slough are excessive erosion of the salt marsh
    along the main channel from the construction of Moss Landing Harbor
    in 1947, which changed the slough from a depositional to an
    erosional environment; many non-native invertebrates in the benthos;
    predation of Snowy Plover eggs by feral red fox; an expanding raven
    population, which also is expected to prey on Snowy Plover eggs;
    avian predation of Snowy Plover chicks; agricultural run-off
    contaminating water and sediments with pesticides; degraded salt
    marsh at Moro Cojo Slough from cattle grazing; and water level
    manipulation for mosquito control. Elkhorn Slough is owned by CDFG,
    The Nature Conservancy, and private parties. It is a NOAA National
    Estuary Research Reserve (S. Connors pers. comm.).

    *Salinas River Mouth.* The Salinas River mouth is bordered by the
    Salinas River National Wildlife Refuge and Salinas State Beach. Much
    beach in the area is closed to the public. Nest exclosures also are
    used to protect Snowy Plover eggs from being trampled by people or
    taken by feral red fox, skunks, and gulls. Frequently the river
    mouth closes during the summer allowing the Snowy Plover,
    Black-necked Stilt, and American Avocet to nest more safely on
    islands within a quarter mile of the river mouth. Avocets and stilts
    also nest in pond and marsh areas adjacent to the river on the
    wildlife refuge, whereas the Snowy Plover and Killdeer nest on the
    beach. Water quality of the river is probably poor because of
    agricultural run-off from extensive farmlands upstream. Human
    disturbance and shorebird egg and chick loss to predators are
    management issues at Salinas River mouth (G. Page pers. obs.).

    *Morro Bay.* Morro Bay, a 2,300-acre National and State Estuary, is
    managed for oyster harvesting, fishing, and hunting. It supports
    tens of thousands of migrating and wintering shorebirds, including
    the Black-bellied Plover, Willet, Long-billed Curlew, Marbled
    Godwit, Sanderling, Western Sandpiper, and Least Sandpiper (PRBO
    unpubl. data). The Morro Bay sand spit is an important Snowy Plover
    nesting area. Agencies responsible for Morro Bay oversight include
    the National Guard, CDPR, CDFG, California Department of
    Corrections, State Department of Health Services, California Coastal
    Commission, State Water Resources Control Board, Central Coast
    Regional Water Quality Control Board, Coastal San Luis Obispo
    Resource Conservation District, State Coastal Conservancy,
    California Conservation Corps, California Polytechnic State
    University, San Luis Obispo, University of California Extension,
    County of San Luis Obispo, City of Morro Bay, Los Osos Community
    Services District, U. S. Army Corps of Engineers, USFWS, and U.S.
    National Marine Fisheries Service. Primary management goals are to
    ensure that Morro Bay water remains of sufficient quality to support
    a viable commercial shellfish industry, safe recreation, healthy
    eelgrass beds, and thriving fish and shellfish populations.
    Accelerated rates of sedimentation from human alteration of the
    watershed occur at Morro Bay. The Coastal San Luis Obispo Resource
    Conservation District is addressing this problem through its 1989
    Morro Bay Watershed Enhancement Plan, which focuses on preventing
    and controlling soil erosion. The District acquires watershed
    parcels to reestablish natural flood plains and create sediment
    deposition areas above Morro Bay. Invasion of non-native plants and
    invertebrates also are management issues at Morro Bay. The spit is
    covered with the non-native European beachgrass *(Ammophila
    arenaria)*, which degrades it as a nesting area for the Snowy
    Plover. Many agencies are now cooperatively producing a
    Comprehensive Conservation and Management Plan for Morro Bay and its
    watershed. Management for shorebirds is expected to be compatible
    with other management goals (K. Kropp pers. comm.).

    *Santa Maria River Mouth.* The Santa Maria River mouth is usually
    closed to tidal action. The sand beach and river flats are used by
    hundreds of shorebirds, especially the Black-bellied Plover, Snowy
    Plover, Willet, and Sanderling. Dry river flats and adjacent beach
    are important Snowy Plover nesting areas. The river mouth
    occasionally experiences oil discharges from a former production
    field encompassing the area (G. Page pers. obs.).

    *Devereaux Slough.* This 8.7-acre salt marsh with channels has been
    altered historically and subjected to excessive rates of
    sedimentation. The area is used by hundreds of migrating and
    wintering shorebirds, and an adjacent beach is an important
    wintering and potential nesting area for the Snowy Plover. Located
    in the area is the Coal Oil Point Preserve, owned and managed by the
    University of California. Important mangement issues for the area
    are exotic plants, nest predation by introduced and native
    predators, human disturbance, and mosquito abatement practices. A
    management plan is being prepared to reduce disturbance to wintering
    Snowy Plovers. Management goals for the region that could benefit
    shorebirds, and especially wintering Snowy Plovers, include limiting
    human access to trails, enforcing pet restrictions, reducing
    nighttime recreation activities, controlling feral red fox and
    raccoons *(Procyon lotor),* and enforcing parking restrictions (K.
    Lafferty pers. comm.).

    *Mugu Lagoon.* This 1479-acre estuary, within Mugu Naval Air
    Station, is owned and managed by the U.S. Navy. There are 129 acres
    of tidal flats, 77 acres of salt pan, 946 acres of tidal marsh, and
    327 acres of channels, creeks, and open water. The lagoon is used by
    tens of thousands of migrating and wintering shorebirds and modest
    numbers of nesting Snowy Plovers, Black-necked Stilts, and American
    Avocets. Mugu Lagoon is impacted by run-off from the large adjacent
    agricultural area, which enters the lagoon through Calleguas Creek.
    The most serious threat is increased sedimentation from development
    of the watershed. Pollutants -- including lead, mercury, silver, and
    methoxychlor -- have been detected at or above hazardous levels in
    drains to the lagoon. The lagoon mouth also closes periodically
    affecting sedimentation rates. A fish and wildlife plan has existed
    since 1963 and was amended in 1976 (Onuf 1987, Harrington and Perry
    1995).

    *Malibu Lagoon.* Malibu Lagoon, fed by Malibu Creek, provides about
    92 acres of wetland habitat. It is owned and managed by CDPR.
    Although surrounded on three sides by residential, commercial, and
    recreational developments, the wetland's tidal flat, salt marsh, and
    beach habitats support a wide variety of migrating and wintering
    shorebirds (L. Hays pers. comm.).

    *Los Angeles River Mouth.* Once part of one of the largest flood
    plains in the United States, the Los Angeles River is now entirely
    channelized and operated primarily as a flood control facility by
    the Los Angeles Department of Water and Power and the U.S. Army
    Corps of Engineers. Within the intertidal portion of the river,
    extending inland from the mouth about 2.6 miles to the Willow Street
    crossing in Long Beach, are approximately 234 acres of wetlands,
    which provide shorebird habitat when water levels are low. Although
    the river upstream of Willow Street has a cement bottom, a 4-mile
    stretch, equivalent to about 40 acres of river channel, annually
    holds thousands of shorebirds during migration (L. Hays pers.
    comm.).

    *San Gabriel River Mouth.* The San Gabriel River Mouth/Los Cerritos
    /Hellman Ranch wetland complex, located primarily in the City of
    Long Beach, contains a minimum of 155 acres of wetland habitat
    exclusive of the San Gabriel River channel. Hundreds of shorebirds
    use the complex. The river channel is mostly subtidal and not
    extensively used by shorebirds. Adjacent to the channel, within the
    Los Cerritos wetlands, are 19 acres of salt marsh, about 18 acres of
    diked wetlands, 8 acres of tidal mudflat, and 95 acres of subtidal
    habitat. Although the salt marsh north of Westminister Avenue is
    open to tidal action, levees isolate the remaining marsh from the
    tides. The Hellman Ranch wetland, adjacent to the San Gabriel River
    and about 1 mile upstream from the mouth, consists of 3 acres of
    tidal channel, 15 acres of degraded salt marsh, 2 acres of seasonal
    ponds, and 7 acres of alkaline flats. The Cerrito and Hellman Ranch
    wetlands are mostly privately owned (L. Hays pers. comm.).

    *Seal Beach NWR.* The approximately 1,000-acre Seal Beach National
    Wildlife Refuge lies within the 1,255-acre Anaheim Bay wetland
    complex, which includes 565 acres of salt marsh, 60 acres of tidal
    flat, 114 acres of tidal channels and ponds, and 475 acres of
    human-created waterways and open water. Thousands of shorebirds
    occur here during migration and winter, feeding primarily on tidal
    flats; some rocky coast species forage on rock jetties. Over 2,000
    acres of surrounding agricultural land, mostly in row crops, buffer
    the wetlands on two sides from dense urban development and provide
    additional foraging habitat for wintering shorebirds. About a dozen
    Black-necked Stilts breed in the wetlands. Anaheim Bay's wetlands
    have been reduced to about half their former extent during the past
    150 years by diking and filling for agriculture and construction of
    a railway and interstate highway through the marsh, an ammunition
    depot with connecting harbor, a marine-oriented residential
    community, and an oil pumping facility. There is a potential for
    further habitat loss and degradation from development. Habitat also
    has been altered by the introduction of non-native invertebrates
    into the benthic invertebrate community and probably by chemical
    contamination of water and sediments from the oil facility and motor
    boats. Feral red fox, feral cats, and stripped skunks *(Mephitis
    mephitis)* impact the reproductive success of nesting birds. The
    Seal Beach National Wildlife Refuge, contained within the U.S.
    Navy's Seal Beach Naval Weapons Station, is managed to maintain the
    quality of wetland habitat, prevent human intrusion, protect
    threatened and endangered species, and reduce predation pressure on
    nesting birds. Feral red fox populations have been controlled on the
    refuge but not in surrounding areas. Human disturbance and habitat
    needs of endangered species, such as the Light-footed Clapper Rail
    and Belding Savannah Sparrow, are wildlife management issues.
    Protection and restoration of adjacent historic coastal wetlands and
    protection of high tide roosting areas are actions that would
    benefit shorebirds at the refuge (J. Bradley pers. comm.).

    *Bolsa Chica.* Although recently threatened with development, all
    1,300 acres of the Bolsa Chica wetlands are now in state ownership.
    A project is underway to remove oil field infrastructure and restore
    tidal influence to about 700 acres, which will create large tidal
    flats; the largest seasonal ponds and flats will be retained for
    shorebirds and other species. The existing 330-acre Bolsa Chica
    Ecological Reserve is managed by CDFG. It consists of open water,
    tidal marsh, sandy islands, and 80 acres of tidal flats. The
    remaining 1,000 acres contain an operating oil field with extensive
    areas of seasonal ponds and non-tidal flats. Bolsa Chica supports
    nesting Snowy Plovers, Black-necked Stilts, American Avocets, and
    thousands of migrating and wintering shorebirds. It is smaller than
    150 years ago. Remaining habitat is degraded by invasive non-native
    plants, non-native benthic invertebrates, and restricted tidal
    circulation. Introduced mammalian predators impact nesting birds.
    Human disturbance and habitat needs of endangered species also are
    wildlife management issues. Bolsa Chica currently is protected to
    provide nesting, feeding, and roosting habitat for aquatic birds,
    especially listed species, including the Snowy Plover. Shorebirds
    will benefit from a new tidal entrance for the Ecological Reserve
    and the wetland habitat restoration being undertaken on the oil
    field (Hays 1985, E. Burres and L. Hays pers. comm.).

    *Santa Ana River Mouth.* Located about half way between Bolsa Chica
    and Upper Newport Bay, the Santa Ana River mouth accommodates a
    large array of shorebirds much of the year, including the
    Black-bellied Plover, Semipalmated Plover, Willet, Long-billed
    Curlew, Marbled Godwit, Western Sandpiper, Least Sandpiper, and
    Long-billed Dowitcher. Although fully channelized at the mouth and
    considerably smaller than the 2,950-acre footprint of historic
    wetlands, the Santa Ana River, adjacent U.S. Army Corps of Engineers
    (USACE) mitigation wetlands, and Huntington Beach wetlands contain
    developing salt marsh, over 60 acres of tidal mudflat, and diked
    wetlands under consideration for restoration to full tidal
    influence. The USACE mitigation has established a tidal channel,
    salt marsh, and island nesting habitats. Although much of the Santa
    Ana River mouth is undeveloped and used for recreation and flood
    control purposes, oil field operations continue to the northeast.
    Ownership includes the CDPR (Huntington State Beach); Orange County;
    the Cities of Huntington Beach, Costa Mesa, and Newport Beach; and
    private parties (L. Hays pers. comm.).

    *Upper Newport Bay.* Upper Newport Bay, fed by San Diego Creek and
    Delhi Channel, consists of nearly 1,400 acres of open water, salt
    marsh, freshwater marsh, and tidal mudflat. Thousands of shorebirds
    forage on the mudflats much of the year. Willets, Long-billed
    Curlews, and Marbled Godwits also feed in the salt marsh. Many
    species forage in the freshwater marsh, and the Black-necked Stilt
    and American Avocet nest there. Upper Newport Bay was heavily used
    for salt extraction until the salt works were destroyed by San Diego
    Creek flood waters. Marinas have been constructed, and now the bay
    is used intensively for motor boating, camping, and kayaking. There
    has been accelerated sedimentation from watershed development,
    degraded water quality, invasion of salt marsh by pampas grass, and
    introduction of non-native invertebrates into the benthos. There is
    a risk of further habitat alteration from development. Within the
    bay, the 729-acre Upper Newport Bay Ecological Reserve is owned by
    the State Lands Commission and managed cooperatively by CDFG and
    Orange County as a mix of marsh, mudflat, and open water for
    migrating and wintering shorebirds and other aquatic species.
    Important management issues are reduced tidal circulation,
    disturbance from human recreation, and habitat needs of endangered
    species, such as the California Least Tern *(Sterna antillarun
    browni)*. Shorebirds would benefit from improving water quality,
    removing non-native vegetation, and limiting human disturbance (E.
    Burres and L. Hays pers. comm.).

    *San Joaquin Marsh*. Located west of Upper Newport Bay Ecological
    Reserve and connected to it by a 0.6-mi stretch of San Diego Creek,
    the 492-acre San Joaquin Marsh includes about 305 acres of seasonal
    ponds, freshwater marsh, and seasonally-wet meadows. The San Joaquin
    Marsh is the largest coastal freshwater marsh in California; Campus
    Drive effectively splits it into east and west parcels. The
    University of California owns the 202-acre San Joaquin Freshwater
    Marsh Preserve and Irvine Ranch Water District owns the remainder of
    the area. Although not managed specifically for shorebirds, drying
    seasonal ponds provide varying amounts of non-tidal flats, which
    support hundreds (occasionally thousands) of small and large
    sandpipers, stilts, and avocets. The flats are an important feeding
    area for shorebirds that commute from Upper Newport Bay,
    particularly during high tides. Seasonal pond and marsh habitats are
    currently being restored; construction of islands within some of the
    larger pond cells has increased numbers of nesting Black-necked
    Stilts and American Avocets (L. Hays pers. comm.).

    *Santa Margarita River Mouth.* The Santa Margarita River mouth,
    owned and managed by the U.S. Marine Corps (USMC), covers about 268
    acres west of Interstate 5. It includes 95 acres of salt marsh, 35
    acres of open water, 7 acres of mudflat, 6 acres of brackish marsh,
    and 125 acres of salt flat. Formerly, there were about 370 acres of
    tidal channels and marsh. The Del Mar Boat Basin was carved out of
    153 acres, and until 1970 the marines used the salt flats of the
    estuary for tank training exercises. Prior to 1940 the estuary mouth
    remained open year round but it has since closed periodically,
    probably as a result of the construction of breakwaters at
    Oceanside. In 1965 the river channel was dredged deeper for
    waterfowl, and in 1971 the brackish marsh on the north side of the
    estuary was dredged to make a salt marsh (Marcus and Kondolf 1989).
    The beach and salt flats are an important nesting area for the Snowy
    Plover (A. Powell pers. comm.) and a foraging and roosting area for
    many other species of shorebirds (PRBO unpubl. data). The USMC
    protects nesting California Least Terns by erecting large
    enclosures, within which some Snowy Plovers also nest.

    *Agua Hedionda Lagoon.* The 400-acre Agua Hedionda Lagoon has been
    fully tidal since it was dredged and its mouth stabilized with
    jetties in 1954 (Marcus and Kondolf 1989). While tidally well
    flushed, there is relatively little tidal mudflat (L. Hays pers.
    comm.). Historically it held a great deal more salt marsh than it
    does today (Marcus and Kondolf 1989). Roads separate Agua Hedionda
    Lagoon into three regions. San Diego Gas and Electric owns most of
    the lagoon, part of which serves as a deepwater reservoir for
    cooling water for a power plant. The eastern basin, operated by the
    City of Carlsbad for recreational boating, contains a marina. Two
    hundred acres of the eastern end are managed by CDFG as an
    Ecological Reserve. Large sediment inflows from agricultural land
    around the lagoon are a management problem (Marcus and Kondolf
    1989).

    *Batiquitos Lagoon.* Batiquitos Lagoon's 600 acres are divided by
    roads and a railway. From 1901 to 1910 there were 25 acres of
    commercial salt ponds. Although historically fully tidal, excessive
    sedimentation reduced the tidal prism to a fraction of its former
    size; the lagoon rarely opened to tidal influence after the 1940s
    (Marcus and Kondolf 1989). It was dredged and reopened to tidal
    influence in 1996 and now has extensive tidal mudflat and high tide
    roosting areas available to shorebirds (L. Hays pers. comm.). It is
    owned by the State Lands Commission and CDFG, which manages the
    eastern and middle basins as an Ecological Reserve (L. Hays pers.
    comm.). The lagoon has been impacted from historic habitat loss and
    is at risk to further degradation from future development. It also
    is subject to accelerated rates of filling, reduced tidal
    circulation, poor water quality, detrimental agricultural practices
    in the watershed, non-native invertebrates in the benthos, and
    invasive plant species (T. Dillingham pers. comm.). Excessive rates
    of nest predation by introduced and native predators and human
    disturbance are management issues. Thirty-two acres are actively
    managed as nesting habitat for the California Least Tern and Snowy
    Plover. There is an erosion control plan for the watershed.
    Shorebirds will benefit by maintaining the lagoon opening to the
    ocean and limiting sediment input from the watershed (T. Dillingham
    pers. comm.).

    *San Elijo Lagoon***.** Historically, the 530-acre San Elijo Lagoon
    was fully tidal, but from 1880 to1940 roads, a railway, duck ponds,
    and sewage ponds were constructed, causing it to become brackish and
    rarely experience tidal flows (Marcus and Kondolf 1989). Currently
    an endowment enables maintenance of the lagoon mouth and restoration
    of tidal influence (L. Hays pers. comm.). Extensive areas of tidal
    mudflat have been revived. The lagoon is owned by CDFG, San Diego
    County, San Elijo Foundation, and private owners. CDFG manages the
    eastern and middle basins as an Ecological Reserve (Marcus and
    Kondolf 1989). The lagoon has been impacted by historic habitat loss
    and is at risk to further degradation from future development. It
    also is subject to accelerated rates of filling, reduced tidal
    circulation, poor water quality, detrimental agricultural practices
    in the watershed, and invasive plant species. Important management
    issues are excessive rates of nest predation by introduced and
    native predators, human disturbance, and mosquito abatement
    practices. Ten acres of the Ecological Reserve are actively managed
    for waterfowl, shorebirds, and endangered species. Water levels in
    the lagoon are managed by the San Elijo Lagoon Conservancy through a
    Memorandum of Understanding with the County of San Diego. Shorebirds
    would benefit from improved tidal circulation achieved through
    restoration projects (T. Dillingham pers. comm.).

    *San Dieguito Lagoon***.** Historically, San Dieguito Lagoon was
    fully tidal and the largest of San Diego County's six lagoons but
    has been reduced from probably 1,000 to 300 acres. Between 1905 to
    1970 the marsh was filled for roads, a racetrack, a fair grounds, a
    shopping center, and a military airfield; much of the San Dieguito
    River, which flowed into the lagoon, was impounded. Treated waste
    water was dumped in the lagoon for 20 years. By the 1940s the lagoon
    mouth closed most years, but in 1983 tidal action was restored to 70
    acres. Although San Dieguito Lagoon is mostly privately owned, CDFG
    owns and manages 107 acres of restored wetland as an Ecological
    Reserve and the City of San Diego owns a 20-acre abandoned sewage
    treatment pond and 29 acres of wetlands (Marcus and Kondolf 1989).
    Ten acres of the Ecological Reserve are managed for nesting
    California Least Terns and Snowy Plovers, but the managed site is
    inadequate and should be relocated (T. Dillingham pers. comm.). The
    Ecological Reserve is impacted by accelerated rates of
    sedimentation, reduced tidal circulation, agriculture in the
    watershed, invasive plants, and excessive nest predation by
    introduced and native predators. Human disturbance also is a
    management issue. Shorebirds could benefit from multi-agency actions
    to increase the amount of wetland habitat around the reserve. A
    project to restore an additional 135 acres to regular tidal
    influence and create tidal mud flats is imminent (T. Dillingham
    and L. Hays pers. comm.).

    *Los Penasquitos Lagoon.* The 630-acre Los Penasquitos Lagoon is
    bisected by a major railway and highway. Once fully tidal, it has
    been closed to such action for years. Shorebird use is low because
    there is little tidal mudflat or unvegetated habitat. Problems are
    sedimentation and lack of tidal flats. CDPR owns and manages most of
    the lagoon as part of Torrey Pines State Reserve. The Coastal
    Conservancy is another owner (Marcus and Kondolf 1989).

    *Mission Bay/San Diego Flood Control Channel.* This 4,600-acre area
    was once a deep water embayment. After the USACE diverted the San
    Diego River from San Diego Bay to Mission Bay, sediment began to
    rapidly fill False Bay (part of Mission Bay) making it very shallow
    by the turn of the century. Mission Bay was then dredged to create a
    park complex of islands and is now used primarily as a recreation
    area. Extensive tidal beaches now surround Mission Bay, and large
    expanses of mudflat occur at the edge of the Kendall Frost Marsh
    Preserve. This preserve and Famosa Slough (37 acres) contain the
    only remnants of native marsh. Tributary streams carry in urban
    pollutants, and sewage lines occasionally back up into the bay
    (Marcus and Kondolf 1989). Most of area is owned by the City of San
    Diego, but the University of California Natural Land and Water
    Reserve System owns Kendall Frost Marsh Preserve (Marcus and
    Kondolf 1989) and the City of San Diego owns Famosa Slough. Mission
    Bay has been subject to historic habitat loss, the spread of
    non-native plants, nest predation by introduced mammals, and the
    introduction of non-native invertebrates into the benthic
    invertebrate community. Key management issues are disturbance from
    human recreation, needs of endangered species, and, at Famosa
    Slough, poor water quality and reduced tidal circulation. At Famosa
    Slough, tidal restoration projects are proceeding. Shorebirds would
    benefit from a trail system with educational signs to reduce
    disturbance (L. Hays and R. Stribley pers. comm.).

    *San Diego Bay.* San Diego Bay consists of 11,130 acres of subtidal
    and intertidal habitat and 1,400 acres of salt ponds (M. Mailander
    pers. comm.). In 1850, there were nearly solid mudflats around the
    bay but only half (766 acres) remains today. After the San Diego
    River was diverted, the large marsh at the river delta was filled
    and built on by the City of San Diego. The bay has been dredged to
    fill tide lands, widen beaches along Silver Strand, and create
    military and domestic ports. The dredged area is much deeper and
    narrower than 150 years ago. Only the south bay contains significant
    areas of marsh, mudflat, and salt ponds (Marcus and Kondolf 1989).
    Tidal mudflats are the main shorebird feeding area; the salt ponds
    provide additional feeding and roosting habitat (Terp 1998). The San
    Diego Unified Port District (SDUPD) administers 37% of the bay
    (includes both submerged and historic tidelands), the State Lands
    Commission retains ownership of 42%, and the military controls
    almost 20% (Marcus and Kondolf 1989). Over half the salt ponds are
    privately owned; the remainder are owned by the State Lands
    Commission. The USFWS owns and manages the entire 315-acre
    Sweetwater/Paradise Marsh complex and manages the salt works as part
    of the national wildlife refuge system (B. Collins pers. comm.).
    Sweetwater Marsh consists of salt and brackish marsh, salt pan,
    mudflats, fill, and upland and supports breeding Snowy Plovers and
    many species of migrating and wintering shorebirds (B. Collins pers.
    comm.). The SDUPD manages the Emory Cove Reserve (8.5 acres), Chula
    Vista Wildlife Reserve (72 acres), and D Street Fill (13-20 acres).
    The latter are is managed jointly with the USFWS, principally for
    nesting California Least Terns and Snowy Plovers. At Chula Vista
    Wildlife Reserve, the primary management goal is to preserve the 14
    acres of subtidal habitat, 35 acres of mudflat, 11 acres of salt
    flat, and 12 acres of sand and dune substrate for the long-term
    benefit of migrating and wintering shorebirds and for nesting Snowy
    Plovers, California Least Terns, and Belding Savannah Sparrows.
    SDUPD and the U.S. Navy currently are developing a baywide
    management plan (M. Mailander pers. comm.).

    *Tijuana River Estuary.* Since 1852 the Tijuana River Estuary has
    lost 80% of its tidal prism and 250 acres of the southern arm to
    sedimentation and agricultural reclamation. Apartments have been
    erected on most of the northern dunes. In 1983 the mouth closed and
    had to be dredged; now it is susceptible to periodic closure (Marcus
    and Kondolf 1989). Today the approximately 1,320-acre Tijuana River
    Estuary is included within the 2,531-acre NOAA Tijuana River
    National Estuarine Research Reserve consisting of tidally flushed
    wetland, riparian habitat, and upland. The area is owned and managed
    cooperatively by the CDPR (Border Field State Park), USFWS (Tijuana
    Slough National Wildlife Refuge), City and County of San Diego, and
    U.S. Navy (B. Collins pers. comm.). Beside supporting thousands of
    migrating and wintering shorebirds, the Tijuana River Estuary is a
    nesting area for the Snowy Plover, Black-necked Stilt, and American
    Avocet. Management issues are accelerated sedimentation, reduced
    tidal circulation, exotic plants, introduced benthic invertebrates,
    clutch predation of nesting shorebirds by native and non-native
    predators, and human disturbance. USFWS manages for nesting Snowy
    Plovers and California Least Terns through closed areas and predator
    control. Projects to improve tidal circulation have been recently
    completed or are planned for the near future. The USFWS annually
    works on dune stabilization north of the river mouth to protect
    Oneonta Slough from sand deposition. USFWS projects in the planning
    stage include dune restoration south of the river mouth (including
    exotic vegetation removal) and a sediment control project in the
    Goat Canyon watershed (B. Collins pers comm.).

    Priority conservation actions for southern California coastal
    wetlands are to:

-   Acquire, and enhance for migrating and wintering shorebirds,
    privately owned wetland parcels at Moro Cojo Slough and Porter
    Marsh, Elkhorn Slough.

-   Provide incentives for landowners to reduce run-off (sediment and
    agricultural chemicals) from farmland into Elkhorn Slough.

-   Improve tidal circulation to increase mudflat exposure in Kirby
    Marsh, Elkhorn Slough.

-   Enforce boat speed limits to reduce bank erosion along the main
    channel of Elkhorn Slough.

-   Increase predator control to improve nesting success of the Snowy
    Plover, Black-necked Stilt, and American Avocet at Moss Landing
    Wildlife Area and Porter Marsh, Elkhorn Slough.

-   Repair water control structures to better manage water levels for
    nesting and wintering shorebirds at Moss Landing Wildlife Area,
    Elkhorn Slough.

-   Remove cattle to eliminate degradation of salt marsh at Moro Cojo
    Slough, Elkhorn Slough.

-   Support the Coastal San Luis Obispo Resource Conservation District's
    efforts to reduce watershed erosion at Morro Bay.

-   Allow sediment to accrete in the concrete channel of Los Angeles
    River to increase microhabitat heterogeneity, particularly at the
    river mouth.

-   Regulate water flows at Los Angeles River mouth to provide shallow
    water for foraging shorebirds.

-   Restore tidal action to at least 60 acres of diked and other
    degraded habitats in the Los Cerritos and Hellman Ranch areas at San
    Gabriel River.

-   Acquire and restore tidal flow to at least 100 acres of degraded
    diked wetlands east of the river channel at Santa Ana River mouth.

-   Prevent unnecessary grading and removal of channel sediments at
    Santa Ana River mouth to increase the extent and heterogeneity of
    mudflats.

-   Expand Seal Beach NWR at Anaheim Bay by 200 acres through
    acquisition of adjacent wetland habitat; enhance acquired habitat
    for nesting, migrating, and wintering shorebirds.

-   Remove fill from Shellmaker Island and other locations in Upper
    Newport Bay to increase intertidal habitat.

-   Restrict boat and kayak traffic from areas used heavily by foraging
    and roosting shorebirds at Upper Newport Bay.

-   Maintain closures and increase predator control in shorebird nesting
    areas in the northeastern part of the Ecological Reserve at Upper
    Newport Bay.

-   Reduce the need for frequent dredging projects at Upper Newport Bay.

-   Install silt traps in the creek above Michelson Drive to avoid
    shorebird habitat loss at San Diego Creek mouth, Upper Newport Bay.

-   Create additional marsh and pond habitat for shorebirds by restoring
    flow to currently degraded wetlands at San Joaquin Marsh.

-   Manage island vegetation to improve shorebird nesting, foraging, and
    roosting habitat at San Joaquin Marsh.

-   Manage pond water levels to protect shorebird nesting sites and
    provide shorebird foraging habitat at San Joaquin Marsh.

-   Maintain salt pond habitat for migrating phalaropes and nesting
    Snowy Plovers at San Diego Bay.

    **Monitoring Priorities**

    Priority monitoring needs for the southern California coast are to:

-   Annually monitor shorebirds in coastal wetlands for long-term trends
    in abundance.

-   Maintain fall, winter, and spring shorebird monitoring at Upper
    Newport Bay.

-   Monitor numbers, distribution, reproductive success, and predator
    impact on nests of the Black-necked Stilt and American Avocet at
    Upper Newport Bay, San Joaquin Marsh, and Tijuana River Estuary.

    **Research Priorities**

    Priority research needs for the southern California coast are to:

-   Identify the time of year each site is important to shorebirds.

-   Identify beaches important to migrating and wintering shorebirds.

-   Determine numbers and distribution of nesting Killdeers,
    Black-necked Stilts, and American Avocets along the coast.

-   Evaluate shorebird use of tidally-restricted wetlands relative to
    tide and water level at Elkhorn Slough.

-   Identify uplands important for foraging and roosting shorebirds in
    winter at Elkhorn Slough.

-   Determine physical characteristics of wetlands important to
    shorebirds at Elkhorn Slough.

-   Evaluate the seasonal importance of mudflat, salt marsh, and managed
    pond habitat to shorebirds at Elkhorn Slough.

-   Measure contaminant levels in the invertebrate prey base and fish
    populations of important shorebird foraging areas at Elkhorn Slough.

-   Quantify contaminant levels in shorebirds and their prey at Los
    Angeles and Orange county wetlands known to contain residual
    deposits of DDT.

-   Investigate the causes of shorebird movement among wetlands to
    facilitate adaptive habitat management of Orange County wetlands.

-   Evaluate how periodic sewage spills affect shorebird food supply at
    Tijuana River Estuary.

-   Determine the level of disturbance to shorebirds from illegal border
    crossings and activities of the Border Patrol to stop perpetrators
    at Tijuana River Estuary.

-   Determine patterns of shorebird seasonal use of different wetland
    regions of Elkhorn Slough.

-   Assess predator impact on Black-necked Stilt and American Avocet
    nesting success at the Moss Landing Wildlife Area and Porter Marsh,
    Elkhorn Slough.

-   Study shorebird use of soft-bottomed portions of the river channel
    relative to substrate disturbances and water column depth at Los
    Angeles River.

-   Assess the degree of shorebird movement among portions of Upper
    Newport Bay and nearby wetlands, such as San Joaquin Marsh, Santa
    Ana River, and Bolsa Chica.

-   Assess the short- and long-term effects of periodic dredging on
    shorebirds at Upper Newport Bay.

-   Study the impacts of nighttime predators on shorebird eggs and
    chicks at Tijuana River Estuary.

-   Evaluate shorebird use of habitats within Tijuana River Estuary.

### Education Priorities {#education-priorities-1 .unnumbered}

Education priorities for the subregion are to:

-   Support existing education, outreach, and interpretive programs at
    all sites.

-   Initiate focused shorebird conservation and education programs.

-   Disseminate information on research-driven adaptive management
    techniques.

### Funding Priorities {#funding-priorities .unnumbered}

Funding priorities for the subregion are to:

-   Support a shorebird plan coordinator for the Southern California
    Coast Subregion; estimated cost \$100,000 annually.

-   Fund habitat restoration projects; estimated cost \$2,000,000
    annually for 10 years.

    **Implementation and Coordination**

    Because shorebird habitat in the Southern California Coast Subregion
    is owned and managed by so many parties and there is no southern
    California joint venture, we believe a coordinator should be hired
    to implement the plan in this subregion. A partial list of the many
    organizations and agencies with regulatory or management
    responsibilities in the California coastal zone that might
    participate in the shorebird conservation plan include:

    California Coastal Commission -- regulatory responsibilities at all
    sites.

    California Department of Fish and Game -- Elkhorn Slough, Morro Bay,
    Bolsa Chica, Upper Newport Bay, Agua Hedionda Lagoon, Batiquitos
    Lagoon, San Elijo Lagoon, and San Dieguito Lagoon.

    California Department of Parks and Recreation -- Pacifica Beach,
    Half Moon Bay beaches, San Gregorio Creek, Pomponia Beach, Pescadero
    Beach, Gazos Creek, Año Neuvo beaches, Waddell Creek, Baldwin Creek,
    Seabright Beach, Monterey Bay beaches, Pajaro River mouth, Salinas
    River mouth, Asilomar Beach, Point Sur Beach, San Simeon Beach,
    Atascadero Beach, Morro Bay, Pismo Beach, Carpinteria Beach, San
    Buenaventura Beach, Mandalay Bay to Santa Clara River mouth beach,
    Malibu Lagoon, Huntington Beach, Santa Ana River mouth, Doheny
    Beach, Agua Hedionda Lagoon, South Carlsbad Beach, San Elijo Lagoon,
    Los Penasquitos Lagoon, and Tijuana River Estuary.

    City of Carlsbad -- Agua Hedionda Lagoon.

    Cities of Costa Mesa, Huntington Beach, Newport Beach -- Santa Ana
    River mouth.

    City of Del Mar -- San Dieguito Lagoon Beach.

    City of Hermosa -- Hermosa Beach.

    City of Morro Bay -- Atascadero Beach and Morro Bay.

    City of Long Beach -- San Gabriel River mouth.

    City of Oceanside -- San Luis Rey River mouth.

    City of Oxnard -- Ormond Beach.

    City of Pacifica -- Pacifica Beach.

    City of San Diego -- San Dieguito Lagoon, Mission Bay, San Diego
    Flood Control Channel, Ocean Beach, and Tijuana River Estuary.

    City of Santa Monica -- Santa Monica Beach.

    City of Ventura -- San Buenaventura Beach.

    Irvine Water District -- San Joaquin Marsh.

    Los Angeles County -- Zuma Beach and Corral Beach.

    Los Angeles Department of Water and Power -- Los Angeles River
    mouth.

    The Nature Conservancy -- Elkhorn Slough, Nipomo Dunes, and Santa
    Cruz Island beaches.

    Orange County -- Santa Ana River Mouth, Upper Newport Bay, Crystal
    Cove Beach, and Salt Creek Beach.

    San Diego County -- San Elijo Lagoon and Tijuana River Estuary.

    San Diego Gas and Electric -- Agua Hedionda Lagoon.

    San Diego Unified Port District -- San Diego Bay.

    The San Elijo Foundation -- San Elijo Lagoon.

    The San Elijo Lagoon Conservancy -- San Elijo Lagoon.

    Santa Barbara County -- Jalama Beach.

    Santa Cruz County -- Scott Creek Beach.

    State Water Control Board -- Morro Bay.

    State Lands Commission -- Upper Newport Bay and San Diego Bay.

    U.S. Air Force -- Vandenberg Air Force Base beaches, including Santa
    Ynez River mouth and Jalama Beach.

    U.S. Army Corps of Engineers -- Los Angeles River Mouth and Santa
    Ana River mouth.

    U.S. Fish and Wildlife Service -- Salinas River Mouth, Morro Bay,
    Anaheim Bay, San Diego Bay, and Tijuana River Estuary.

    U.S. Marine Corps -- San Onofre Beach, Aliso Creek, French Creek,
    and Santa Margarita River mouth.

    U.S. National Oceanic and Atmospheric Administration -- Elkhorn
    Slough, Morro Bay, and Tijuana River Estuary.

    U.S. National Park Service -- Ocean Beach and beaches of San Miguel
    and Santa Rosa islands.

    U.S. Navy -- Mugu Lagoon, San Nicolas Island, Anaheim Bay, San Diego
    Bay, and San Clemente Island.

    University of California -- Devereaux Slough, San Joaquin Marsh, and
    Mission Bay.

    Various private property owners -- Tunitas Creek, Gazos Creek,
    Elkhorn Slough, Monterey Bay beaches, Point Sur Beach, San
    Carpoforio Creek, Arroyo Hondo Creek, Point Sierra Nevada Beach,
    Arroyo de la Cruz, Sidneys Lagoon, Piedras Blancas Beach, Arroyo
    Laguna Creek, Pico Creek, Villa Creek, Toro Creek, Avila Creek,
    Nipomo Dunes, Hollister Ranch, Hollywood Beach, Ormond Beach, Santa
    Ana River mouth, Corral Beach, Agua Hedionda Lagoon, San Elijo
    Lagoon, San Dieguito Lagoon, and Tijuana River Estuary.

    Ventura County -- beach between Mandalay Bay and Santa Clara River
    mouth, Hollywood Beach, and Dockweiller Beach.

# CENTRAL VALLEY SUBREGION {#central-valley-subregion .unnumbered}

# Description of Subregion {#description-of-subregion-1 .unnumbered}

# The Central Valley -- stretching northwest to southeast through the heart of the state -- is California's largest valley. Surrounded by mountains, except for its western drainage into San Francisco Bay, the Central Valley averages about 400 mi long and 40 mi wide. It is divided into the Sacramento Valley, draining southward, the San Joaquin Valley draining northward, and the Sacramento-San Joaquin River Delta (hereafter Delta) where these rivers converge. The Sacramento Valley is further divided into the Colusa, Butte, Sutter, American, and Yolo drainage basins, and the San Joaquin Valley into the San Joaquin Basin and the, usually closed, Tulare Basin. Further discussion will focus primarily on the four major subdivisions of the Central Valley -- the Sacramento Valley, Delta, San Joaquin Basin, and Tulare Basin. {#the-central-valley-stretching-northwest-to-southeast-through-the-heart-of-the-state-is-californias-largest-valley.-surrounded-by-mountains-except-for-its-western-drainage-into-san-francisco-bay-the-central-valley-averages-about-400-mi-long-and-40-mi-wide.-it-is-divided-into-the-sacramento-valley-draining-southward-the-san-joaquin-valley-draining-northward-and-the-sacramento-san-joaquin-river-delta-hereafter-delta-where-these-rivers-converge.-the-sacramento-valley-is-further-divided-into-the-colusa-butte-sutter-american-and-yolo-drainage-basins-and-the-san-joaquin-valley-into-the-san-joaquin-basin-and-the-usually-closed-tulare-basin.-further-discussion-will-focus-primarily-on-the-four-major-subdivisions-of-the-central-valley-the-sacramento-valley-delta-san-joaquin-basin-and-tulare-basin. .unnumbered}

The Central Valley has lost about 90% of its historic wetlands (Frayer
et al. 1989), and the region is now dominated by agricultural lands.
Readers should consult Heitmeyer et al. (1989) for an overview of the
physiography and extent of historical and recent wetlands and croplands
by subregion of the Central Valley. Primary shorebird habitats in the
Central Valley currently are restored and highly managed wetlands,
flooded agricultural lands, hypersaline agricultural evaporation ponds,
and municipal sewage ponds (Table 2). The Central Valley's vernal pool
rangelands probably also provide important shorebird habitat (Silveira
1998) but use of these pools by shorebirds has been poorly studied.
During comprehensive surveys of shorebirds in the Central Valley in the
early 1990s, managed wetlands, agricultural fields (especially rice),
and agricultural evaporation ponds held the most shorebirds (Shuford et
al. 1998). These authors provide additional detail on habitat use by
various species of shorebird throughout the Central Valley.

# Shorebird Species {#shorebird-species .unnumbered}

# Surveys have shown the Central Valley to be one of the most important regions in western North America for migrating and wintering shorebirds. Shorebird populations in the Central Valley in the early 1990s averaged 134,000 individuals in August, 211,000 in November, 303,000 in January, and 335,000 in April (Shuford et al. 1998). Of 33 species recorded on these surveys, the 10 or 11 that averaged over 1000 individuals each season accounted for 99% of total numbers. In winter and spring, the Central Valley supports more shorebirds than any other inland site in western North America, and in winter is the only inland area, other than California's Salton Sea and Oregon's Willamette Valley, that supports tens of thousands of shorebirds. In fall, it is the second most important inland site to shorebirds after Great Salt Lake, Utah. Shorebird totals in the Valley seasonally range from about 20% to 40% of those on the California coast, but seven species have Valley populations that can exceed those on the coast in at least one season. The Valley is less important as a breeding area for shorebirds, but three species -- Killdeer, Black-necked Stilt, and American Avocet -- nest there in moderate numbers and four species -- Snowy Plover, Spotted Sandpiper, Common Snipe, and Wilson's Phalarope -- breed there in small numbers.  {#surveys-have-shown-the-central-valley-to-be-one-of-the-most-important-regions-in-western-north-america-for-migrating-and-wintering-shorebirds.-shorebird-populations-in-the-central-valley-in-the-early-1990s-averaged-134000-individuals-in-august-211000-in-november-303000-in-january-and-335000-in-april-shuford-et-al.-1998.-of-33-species-recorded-on-these-surveys-the-10-or-11-that-averaged-over-1000-individuals-each-season-accounted-for-99-of-total-numbers.-in-winter-and-spring-the-central-valley-supports-more-shorebirds-than-any-other-inland-site-in-western-north-america-and-in-winter-is-the-only-inland-area-other-than-californias-salton-sea-and-oregons-willamette-valley-that-supports-tens-of-thousands-of-shorebirds.-in-fall-it-is-the-second-most-important-inland-site-to-shorebirds-after-great-salt-lake-utah.-shorebird-totals-in-the-valley-seasonally-range-from-about-20-to-40-of-those-on-the-california-coast-but-seven-species-have-valley-populations-that-can-exceed-those-on-the-coast-in-at-least-one-season.-the-valley-is-less-important-as-a-breeding-area-for-shorebirds-but-three-species-killdeer-black-necked-stilt-and-american-avocet-nest-there-in-moderate-numbers-and-four-species-snowy-plover-spotted-sandpiper-common-snipe-and-wilsons-phalarope-breed-there-in-small-numbers. .unnumbered}

#  {#section-4 .unnumbered}

+-----------+-----------+-----------+-----------+-----------+----------+
| **Table   |           |           |           |           |          |
| 2**       |           |           |           |           |          |
| Extent    |           |           |           |           |          |
| (acres)   |           |           |           |           |          |
| of key    |           |           |           |           |          |
| shorebird |           |           |           |           |          |
| habitats  |           |           |           |           |          |
| in the    |           |           |           |           |          |
| Central   |           |           |           |           |          |
| Valley,   |           |           |           |           |          |
| 1992 to   |           |           |           |           |          |
| 1995      |           |           |           |           |          |
| (from     |           |           |           |           |          |
| Shuford   |           |           |           |           |          |
| et al.    |           |           |           |           |          |
| 1998).    |           |           |           |           |          |
+-----------+-----------+-----------+-----------+-----------+----------+
|           |           |           |           |           |          |
+-----------+-----------+-----------+-----------+-----------+----------+
|           |           |           | Ha        |           |          |
|           |           |           | bitats^a^ |           |          |
+-----------+-----------+-----------+-----------+-----------+----------+
| Basin     | MGWE^b^   | AGLA^b^   | AGRI^c^   | EVAP^d^   | SEPO^e^  |
+-----------+-----------+-----------+-----------+-----------+----------+
| Colusa    | 24,359    | 200,885   | 33,790    | 0         | 136      |
+-----------+-----------+-----------+-----------+-----------+----------+
| Butte     | 23,235    | 156,240   | 61,078    | 0         | 116      |
+-----------+-----------+-----------+-----------+-----------+----------+
| Sutter    | 5093      | 92,958    | 13,452    | 0         | 79       |
+-----------+-----------+-----------+-----------+-----------+----------+
| American  | 7336      | 116,875   | 30,043    | 0         | 274      |
+-----------+-----------+-----------+-----------+-----------+----------+
| Yolo      | 10,305    | 51,532    | 3927      | 0         | 620      |
+-----------+-----------+-----------+-----------+-----------+----------+
| Delta     | 17,389    | 36,791    | 291       | 0         | 1032     |
+-----------+-----------+-----------+-----------+-----------+----------+
| San       | ?^f^      | ?         | ?         | 0         | 2507     |
| Joaquin   |           |           |           |           |          |
+-----------+-----------+-----------+-----------+-----------+----------+
| Tulare    | 15,260    | 132,449   | 0         | 5409      | 3648     |
+-----------+-----------+-----------+-----------+-----------+----------+
| Total     | \_\_\_    | \_\_\_    | 142,581   | 5409      | 8412     |
+-----------+-----------+-----------+-----------+-----------+----------+
| ^a^ MGWE  |           |           |           |           |          |
| = managed |           |           |           |           |          |
| wetlands: |           |           |           |           |          |
| p         |           |           |           |           |          |
| alustrine |           |           |           |           |          |
| habitat   |           |           |           |           |          |
| of        |           |           |           |           |          |
| permanent |           |           |           |           |          |
| and       |           |           |           |           |          |
| seasonal  |           |           |           |           |          |
| marshes;  |           |           |           |           |          |
| AGLA =    |           |           |           |           |          |
| all       |           |           |           |           |          |
| agr       |           |           |           |           |          |
| icultural |           |           |           |           |          |
| lands     |           |           |           |           |          |
| (         |           |           |           |           |          |
| including |           |           |           |           |          |
| r         |           |           |           |           |          |
| icelands) |           |           |           |           |          |
| in winter |           |           |           |           |          |
| with      |           |           |           |           |          |
| standing  |           |           |           |           |          |
| water or  |           |           |           |           |          |
| moist     |           |           |           |           |          |
| soil;     |           |           |           |           |          |
| AGRI =    |           |           |           |           |          |
| ricelands |           |           |           |           |          |
| inte      |           |           |           |           |          |
| ntionally |           |           |           |           |          |
| flooded   |           |           |           |           |          |
| in        |           |           |           |           |          |
| winter;   |           |           |           |           |          |
| EVAP =    |           |           |           |           |          |
| hy        |           |           |           |           |          |
| persaline |           |           |           |           |          |
| agr       |           |           |           |           |          |
| icultural |           |           |           |           |          |
| ev        |           |           |           |           |          |
| aporation |           |           |           |           |          |
| ponds;    |           |           |           |           |          |
| SEPO =    |           |           |           |           |          |
| municipal |           |           |           |           |          |
| sewage    |           |           |           |           |          |
| ponds.    |           |           |           |           |          |
|           |           |           |           |           |          |
| ^b^ Data  |           |           |           |           |          |
| from GIS  |           |           |           |           |          |
| mapping   |           |           |           |           |          |
| of        |           |           |           |           |          |
| satellite |           |           |           |           |          |
| images    |           |           |           |           |          |
| from 3    |           |           |           |           |          |
| Jan 1993, |           |           |           |           |          |
| except    |           |           |           |           |          |
| that      |           |           |           |           |          |
| images    |           |           |           |           |          |
| from 20   |           |           |           |           |          |
| Dec 1992  |           |           |           |           |          |
| used for  |           |           |           |           |          |
| the       |           |           |           |           |          |
| Tulare    |           |           |           |           |          |
| Basin (D. |           |           |           |           |          |
| Kempka in |           |           |           |           |          |
| litt.); ? |           |           |           |           |          |
| = no data |           |           |           |           |          |
| available |           |           |           |           |          |
| for San   |           |           |           |           |          |
| Joaquin   |           |           |           |           |          |
| Basin in  |           |           |           |           |          |
| winter    |           |           |           |           |          |
| 1992-93.  |           |           |           |           |          |
|           |           |           |           |           |          |
| ^c^ Data  |           |           |           |           |          |
| for 6 Jan |           |           |           |           |          |
| 1994 from |           |           |           |           |          |
| Spell et  |           |           |           |           |          |
| al.       |           |           |           |           |          |
| 1995); ?  |           |           |           |           |          |
| = no data |           |           |           |           |          |
| available |           |           |           |           |          |
| for San   |           |           |           |           |          |
| Joaquin   |           |           |           |           |          |
| Basin.    |           |           |           |           |          |
|           |           |           |           |           |          |
| ^d^ The   |           |           |           |           |          |
| 6264      |           |           |           |           |          |
| acres of  |           |           |           |           |          |
| ponds     |           |           |           |           |          |
| active in |           |           |           |           |          |
| 1992      |           |           |           |           |          |
| (Moore et |           |           |           |           |          |
| al. 1990) |           |           |           |           |          |
| had been  |           |           |           |           |          |
| reduced   |           |           |           |           |          |
| to 5409   |           |           |           |           |          |
| acres in  |           |           |           |           |          |
| 1995 (A.  |           |           |           |           |          |
| Toto      |           |           |           |           |          |
| pers.     |           |           |           |           |          |
| comm.),   |           |           |           |           |          |
| and       |           |           |           |           |          |
| s         |           |           |           |           |          |
| tructural |           |           |           |           |          |
| changes   |           |           |           |           |          |
| were made |           |           |           |           |          |
| at some   |           |           |           |           |          |
| remaining |           |           |           |           |          |
| ponds to  |           |           |           |           |          |
| limit     |           |           |           |           |          |
| bird use. |           |           |           |           |          |
| Creation  |           |           |           |           |          |
| of        |           |           |           |           |          |
| m         |           |           |           |           |          |
| itigation |           |           |           |           |          |
| wetlands  |           |           |           |           |          |
| may have  |           |           |           |           |          |
| co        |           |           |           |           |          |
| mpensated |           |           |           |           |          |
| for some  |           |           |           |           |          |
| of these  |           |           |           |           |          |
| habitat   |           |           |           |           |          |
| losses.   |           |           |           |           |          |
|           |           |           |           |           |          |
| ^e^ Data  |           |           |           |           |          |
| from      |           |           |           |           |          |
| Chilcott  |           |           |           |           |          |
| and       |           |           |           |           |          |
| Johnson   |           |           |           |           |          |
| (1991)    |           |           |           |           |          |
| and R.    |           |           |           |           |          |
| Diekstra  |           |           |           |           |          |
| (pers.    |           |           |           |           |          |
| comm.).   |           |           |           |           |          |
| Figures   |           |           |           |           |          |
| are       |           |           |           |           |          |
| minimums; |           |           |           |           |          |
| t         |           |           |           |           |          |
| hroughout |           |           |           |           |          |
| the       |           |           |           |           |          |
| Central   |           |           |           |           |          |
| Valley    |           |           |           |           |          |
| some      |           |           |           |           |          |
| small     |           |           |           |           |          |
| sewage    |           |           |           |           |          |
| ponds not |           |           |           |           |          |
| reported  |           |           |           |           |          |
| and none  |           |           |           |           |          |
| north of  |           |           |           |           |          |
| Chico in  |           |           |           |           |          |
| the Butte |           |           |           |           |          |
| Basin     |           |           |           |           |          |
| reported. |           |           |           |           |          |
|           |           |           |           |           |          |
| ^f^ GIS   |           |           |           |           |          |
| data from |           |           |           |           |          |
| 13 Nov    |           |           |           |           |          |
| 1990 (in  |           |           |           |           |          |
| dry       |           |           |           |           |          |
| winter)   |           |           |           |           |          |
| estimated |           |           |           |           |          |
| 59,408    |           |           |           |           |          |
| acres of  |           |           |           |           |          |
| wetlands  |           |           |           |           |          |
| (R. Spell |           |           |           |           |          |
| in        |           |           |           |           |          |
| litt.);   |           |           |           |           |          |
| recent    |           |           |           |           |          |
| Central   |           |           |           |           |          |
| Valley    |           |           |           |           |          |
| Habitat   |           |           |           |           |          |
| Joint     |           |           |           |           |          |
| Venture   |           |           |           |           |          |
| figures   |           |           |           |           |          |
| estimated |           |           |           |           |          |
| 135,620   |           |           |           |           |          |
| acres (D. |           |           |           |           |          |
| Paullin   |           |           |           |           |          |
| in        |           |           |           |           |          |
| litt.).   |           |           |           |           |          |
+-----------+-----------+-----------+-----------+-----------+----------+

Species with regionally important populations in the Central Valley are
the Black-bellied Plover (winter, spring), Snowy Plover (winter),
Killdeer (winter, summer), Mountain Plover (winter), Black-necked Stilt
(fall-spring), American Avocet (fall-spring), Greater Yellowlegs (fall,
winter), Whimbrel (spring), Long-billed Curlew (fall, winter), Western
Sandpiper (spring), Least Sandpiper (winter), Dunlin (winter), and
Long-billed Dowitcher (fall-spring). A number of these species are
differentially distributed within subregions of the Central Valley
(Shuford et al. 1998), indicating a need to adapt management efforts
locally.

The Central Valley is one of only a few key wintering areas in the World
for the Mountain Plover, a species currently proposed for federal
threatened status (Edson and Hunting 1999, USFWS 1999). The Central
Valley also hosts two other Bird Species of Special Concern in
California, the Snowy Plover and the Long-billed Curlew (CDFG 1992). The
San Joaquin Valley is one of two key inland wintering areas in western
North America for the Snowy Plover (Shuford et al. 1995). See Barnum et
al. (1992) and Roster et al. (1992) regarding Snowy Plovers breeding on
agricultural evaportation ponds in the San Joaquin Valley.

Within the Central Valley, the Grasslands Ecological Area in the San
Joaquin Basin near Los Banos has been designated a WHSRN site of
International Importance to shorebirds. The ricelands and wildlife
refuges of the Sacramento Valley appear to qualify for similar status,
and an application for designation currently is being prepared.

**Regional Population and Habitat Goals**

Priority conservation goals for the Central Valley are to:

-   Increase the wintering population of the Mountain Plover in the
    Central Valley. Create suitable open foraging habitat by managing
    for giant kangaroo rats *(Dipodomys ingens)* and using fire and
    grazing, as appropriate.

-   Increase populations of breeding and wintering Snowy Plovers and
    wintering Long-billed Curlews in the Central Valley.

-   Increase breeding and wintering populations of other shorebirds in
    the Central Valley.

-   Restore, enhance, and manage wetlands with integrated wetland
    management goals, which accommodate the needs of a greater diversity
    of birds, including shorebirds (Isola 1998).

-   Ensure the availability of high quality water for wetlands.

-   Resist fragmentation or loss of existing wetland complexes by urban
    encroachment.

-   Promote management practices in agricultural lands and vernal pool
    rangelands that will provide for a greater diversity of birds,
    including shorebirds. Also promote easements and other options for
    maintaining wildlife-friendly agricultural lands and vernal pool
    rangelands.

-   Reduce use of contaminated agricultural evaporation ponds by
    shorebirds and other waterbirds while creating alternative
    uncontaminated habitats that will mimic historic saline playa
    wetlands thereby maintaining the current mix of waterbird
    communities.

-   Increase shorebird use of sewage ponds or wetlands using treated
    sewage effluent if issues of disease transmission and contaminants
    can be addressed.

    **Habitat Status, Threats, and Management Needs**

    Descriptions of current habitat availability, shorebird habitat use
    patterns, threats to shorebirds, management issues, and needed
    conservation actions are provided below for the major habitat types
    in the Central Valley overall or for the valley's major habitat
    types.

    *Valleywide Habitat Status and Concerns.* Given that 90% of the
    Central Valley's historic wetlands have been lost, the main concerns
    for shorebirds are water availability, poor and sometimes toxic
    water quality, habitat loss and degradation from urbanization, and
    changing agricultural practices (see Shuford et al. 1998). Other
    concerns of lesser or unknown magnitude are disturbance from human
    recreation activities, effects of mosquito control, competing needs
    of other species (e.g., salmon), and improper management (e.g., lack
    of grazing where needed).

    Availability of high quality water is a perennial problem throughout
    the Central Valley because of competition for limited supplies among
    agricultural, urban, and wildlife uses. Shorebirds should, however,
    benefit from the sizeable acreage of habitat recently created for
    waterfowl and dependable supplies secured for wetlands via the
    Central Valley Project Improvement Act. Still, wetlands upon which
    shorebirds depend receive only about 1% of the states' water supply,
    and future legislation potentially could reverse past gains,
    particularly as the state's population and water costs increase. The
    need for increased water supplies to meet the requirements of other
    species, such as salmon, potentially could limit the amount
    available for shorebird habitat. Mosquito control efforts also may
    limit options for managing for shallow-water for shorebirds in
    summer and early fall, when such habitat is particularly in short
    supply.

    Pesticides used on agricultural fields have caused limited direct
    mortality of shorebirds and other species, but they may reduce
    shorebirds' invertebrate prey in winter or perhaps have other
    sublethal effects. Similarly, concern has been expressed about the
    impact on fish and wildlife of chemicals used for mosquito control
    in wetlands (Washino and Dritz 1995). A study at the Sacramento
    National Wildlife Refuge complex in the Sacramento Valley, however,
    suggested that ultra low volume applications of insecticides to
    control adult mosquitoes did not substantially affect the abundance
    of aquatic macro-invertebrates or fish in treated waters (Lawler et
    al. 1995). Still, more needs to be known about the potential effects
    of pesticides on shorebirds or their invertebrate prey.

    Expanding urban development directly threatens wetlands, most
    notably at the Grasslands near Los Banos in the San Joaquin Basin
    and near Yuba City in the Sacramento Valley. Urbanization continues
    to reduce agricultural lands in the Central Valley at a rate among
    the highest of any region in North America (American Farmland Trust
    1995, Sorensen et al. 1997), although the effect on shorebirds is
    undocumented. Similarly, conversion of thousands of acres of land
    valleywide to vineyards, orchards, and row crops likely has reduced
    foraging habitat for shorebirds, particularly species using vernal
    pools and those using uplands, such as the Black-bellied Plover,
    Killdeer, Mountain Plover, Whimbrel, and Long-billed Curlew.

    Although many of the problems listed above are faced by shorebirds
    valleywide, some have been or are restricted primarily to certain
    subregions of the Valley. For example, as recently as the 1980s,
    agricultural drain water used to flood wetlands in the Grasslands
    Ecological Area of the San Joaquin Basin resulted in biological
    accumulation of selenium sufficient to harm reproduction of
    shorebirds and other wildlife (Ohlendorf et al. 1987). Conditions in
    the Grasslands have steadily improved after replacement with
    uncontaminated water in 1985 (references in Shuford et al. 1998).
    Similarly, concentrations of salts and trace elements, such as
    selenium, at agricultural evaporation ponds in the Tulare Basin have
    caused reproductive impairment in the Black-necked Stilt and
    American Avocet (Skorupa and Ohlendorf 1991, Ohlendorf et al. 1993).
    Efforts are being made to reduce use of these ponds by hazing,
    altering their physical structure, and creating nearby
    uncontaminated wetlands. How this has changed the size and species
    composition of shorebird populations in the Tulare Basin is
    currently being examined.

    Because agriculture is by far the dominant land use in the Central
    Valley, any broadscale changes in farming practices could
    tremendously influence shorebird habitat. For example, some
    Sacramento Valley riceland could be lost to the current expansion of
    cotton, a less friendly crop to shorebirds, although 80% of the
    region's riceland is incapable of supporting other economically
    viable crops. Conversely, an increase in flooded acreage of rice
    fields in winter to aid in stubble decomposition should benefit
    shorebirds. In the Tulare Basin, changing irrigation practices in
    recent decades have reduced the amount of shallow-water agricultural
    habitat available to ducks and shorebirds (Barnum and Euliss 1991).
    Concentrations of salts in agricultural fields may lead to
    abandonment of these lands and reversion to habitats less suitable
    to shorebirds.

    Anecdotal evidence suggests invasive exotic plants are degrading
    wetland habitats, but more needs to be known of the extent of this
    problem in the Central Valley. Bermuda grass *(Cynodon dactylon)*
    and knot grass *(Paspalum distichum)* pose problems in the Butte
    Sink and major bypasses of the Sacramento Valley where the water
    table is high.

    Limited anecdotal evidence suggests that human recreational
    activities may potentially cause harm to shorebirds in the Central
    Valley, but this may be a greater issue in coastal areas.

    *Overall Management Needs.* With the limited amount of wetlands now
    available in the Central Valley, it is imperative that remaining
    habitat be managed to maximize the diversity and abundance of
    wetland-dependent species. Studies in ricelands in the Sacramento
    Valley (Elphick and Oring 1998) and managed wetlands of the
    Grasslands in the San Joaquin Valley (Williams 1996) both have shown
    that the greatest diversity of waterbirds in winter is found when
    water depths *average* about 6 inches. Hence, a reduction in water
    depths in these habitats over those of previous management practices
    would benefit shorebirds without harming dabbling ducks. As outlined
    below, a number of other specific management recommendations have
    been made to increase wetland use of shorebirds during winter,
    migratory, and breeding periods.

    *Managed Wetlands.* Managed wetlands on refuges and private duck
    clubs cover about 162,000 to 239,000 acres in the Central Valley
    (Table 2). These wetlands provide important shorebird habitat in the
    Central Valley in winter and, especially, spring, when receding
    water levels expose extensive mudflats. Species that forage
    extensively in shallow water or mudflats in managed wetlands are the
    Killdeer, Black-necked Stilt, American Avocet, Greater Yellowlegs,
    Western and Least sandpipers, Dunlin, and Long-billed Dowitcher. The
    amount of acreage of managed wetlands has increased in the Central
    Valley in recent years, in large part from the efforts of the
    Central Valley Habitat Joint Venture (USFWS 1990).

    Personal communications with refuge and duck club managers indicate
    that most wetlands in the Central Valley currently are managed to
    benefit shorebirds to some degree but that management is habitat-
    rather than species-based. The main management techniques used to
    benefit shorebirds are water level management, slow or staggered
    drawdowns, timing of drawdowns to match periods of peak use,
    mechanical vegetation control (burning, disking, mowing), and
    creation of a variety of habitats and varied topography within and
    among management units. Education is viewed as the best tool to
    convince private landowners to incorporate shorebird management into
    existing wetland management for waterfowl. While most respondents
    indicated their management efforts were successful, few had
    specifically defined goals; monitoring effort varied from regular
    unit-by-unit monitoring to anecdotal observations. Many respondents
    indicated there was inadequate knowledge of shorebird habitat
    requirements. Most land managers indicated that management for
    shorebirds posed little conflict with other management goals, though
    one person felt conflicts could arise if there was a major shift in
    water management to target shorebird use exclusively.

    Williams (1996) studied the responses of shorebirds and other
    waterbirds to late winter and early spring drawdowns of moist-soil
    managed wetlands in the Grasslands of the San Joaquin Valley. During
    winter, shorebird diversity and density increased significantly,
    peaking during the mid-point of drawdowns when habitat diversity was
    greatest. Densities of large shorebirds (Black-necked Stilt,
    American Avocet, yellowlegs spp., dowitcher spp.) and sandpipers
    (Western Sandpiper, Least Sandpiper, Dunlin) in winter correlated
    with availability of habitat 2 to 6 inches and \<2 inches deep,
    respectively. By contrast, densities of shorebirds during spring
    drawdowns were not correlated with the amount of shallow habitat.
    These patterns of shorebird occurrence may at least in part reflect
    patterns of habitat availability on a landscape level across the
    entire Grasslands. Large responses to the provision of shallow-water
    habitat in winter may reflect the usually limited supply of this
    type of habitat in this region at this season. Conversely,
    shorebirds may not respond as well to similar experimental drawdowns
    in spring because shallow water typically is widely available during
    this period when extensive areas of wetland are dewatered for
    moist-soil plant management. A lack of significant response in
    spring also may reflect the transitory and variable use of wetlands
    by migratory shorebirds. Williams (1996) recommended that managers
    could provide for the greatest diversity of waterbirds, including
    shorebirds, by flooding most Grasslands wetlands less deep in autumn
    or partially dewatering them in winter to *average* depths of 6 to 8
    inches.

    Water depth is the most important variable influencing habitat use
    by foraging waterbirds in the late winter and early spring in the
    Grasslands of the San Joaquin Valley (Williams 1996, Safran et al.
    1997, Isola 1998). Isola (1998) identified four waterbird foraging
    groups based on similarities in water depth use. Of these, small
    shorebirds (Western Sandpiper, Least Sandpiper, and Dunlin) foraged
    in waters 0.7 to 1.4 inches deep and large shorebirds (Black-necked
    Stilt, American Avocet, and dowitcher spp.) in waters 2.3 to 4.3
    inches deep. Small shorebirds, particularly Least and Western
    sandpipers, foraged at shallower depths than found at random sites.
    Large shorebirds did not appear, at the level of the individual
    wetland, to select foraging depths that were shallower than random.
    On a landscape level, though, they may have selected wetlands that
    tended to be shallower than other available habitats. Isola
    concluded that differences in observed foraging depth variation
    indicated that habitat use of small shorebirds and, to a lesser
    degree, large shorebirds is more constrained by water depth than
    that of waterfowl.

    A two-year study at Sacramento NWR in the Sacramento Valley showed
    differential shorebird use between a wet and a dry spring and among
    various wetland types (Feldheim et al. 1999). Substantially higher
    peak shorebird numbers in a dry versus a wet year likely reflected
    concentration of shorebirds on the refuge when valleywide habitat
    was limited in the dry year. These results suggest the need to
    tailor management actions to varying climatic conditions. Most
    shorebird species preferred seasonally-flooded marshes or vernal
    pools, but the Long-billed Curlew and Whimbrel preferred watergrass
    production units. Although vernal pools comprised less than 2% of
    the refuge's total available wetland habitat, they held the highest
    shorebird densities, and more species preferred vernal pools than
    other wetland types.

    Priority conservation actions for managed wetlands of the Central
    Valley are to:

-   Promote wetland restoration projects that show high potential to
    benefit shorebirds. Regional experts indicated a few sites or
    regions of the Central Valley that had a high potential for
    large-scale restoration of habitats important to shorebirds. The
    most notable of these were in the Tulare Basin of the southern San
    Joaquin Valley, where a unique opportunity now exists to obtain
    retired agricultural lands with water rights from willing sellers
    (H. T. Harvey and Associates 1998). Still, a dependable and
    substantial water supply will be needed to maximize benefits to
    shorebirds and other wetland-dependent species. Additionally,
    private lands in the South Wilbur Flood Area and the Hacienda Ranch
    hold high potential for wetland restoration if cooperation can be
    obtained from private landowners.

-   Restore, and secure with conservation easements, habitats that have
    been greatly reduced historically, such as playa lake wetlands.

-   Expand current management strategies that benefit shorebirds:

    \(a\) Keep water levels that benefit both waterfowl and shorebirds
    during periods when water is maintained at relatively constant
    levels. *Average* depths of 6 to 8 inches are recommended for
    managed wetlands in the Grasslands (Williams 1996, Safran et al.
    1997, Isola 1998).

    \(b\) Conduct slow (\~2 weeks) and staggered drawdowns of water
    throughout wetland complexes. Slow drawdowns should be discouraged
    in wetlands of high salinity in the Grasslands, as this practice can
    increase salt levels in the soil and impede plant growth (Isola
    1998).

    \(c\) Time drawdowns to coincide with periods of peak shorebird
    abundance and need, such as during migration, or when suitable
    habitat might otherwise be limited. For instance, increase drawdowns
    in the Grasslands during late winter (Jan to mid-Mar) when dynamic
    shallow water habitat is in short supply (Williams 1996, Isola
    1998). Increase the practice of temporary drawdowns in late winter
    to help flush salts from degraded wetlands in the Grasslands.

    \(d\) Mimic historic hydrologic conditions by fluctuating water
    levels in wetlands throughout the winter and spring (Isola 1998).

    \(e\) Design new wetlands based on integrated wetland management
    goals (Williams 1996, Isola 1998). Create a variety of habitats and
    varied topography within and among management units to maximize
    diversity of waterbirds, including shorebirds. When enhancing and
    rehabilitating existing wetlands, take care to maintain habitat and
    topographic diversity. For wetlands with diverse topography with
    varied depths and (generally gentle) elevational gradients,
    *average* depths should be about 6 to 8 inches when fully flooded.
    Less topographically diverse wetlands will have to be flooded more
    shallowly (1-6 inches) to provide shorebird habitat. Gentle grading
    of side slopes of levees, islands, underwater berms, and drainage
    swales should provide structural integrity and greater diversity of
    water depths.

    \(f\) Set vegetation succession back by various means of mechanical
    control, fire, or grazing.

    \(g\) Provide predator-free, sparsely vegetated nesting islands for
    breeding shorebirds, which also may serve as roost sites for other
    shorebirds during the non-breeding season. Islands most suitable for
    shorebirds are low and shallowly sloped, thereby providing shoreline
    foraging areas for both adults and chicks (Engilis and Reid 1996).
    Be careful not to flood nests during spring irrigations or leave
    them high and dry during drawdowns.

-   Coordinate, if possible, management practices over large wetland
    complexes of state, federal, and private lands, such as the
    Grasslands Ecological Area.

-   Devise wet-year, dry-year management strategies to best use water
    when it is available and/or most needed.

-   Work with the Central Valley Habitat Joint Venture in the current
    revision of its waterfowl plan and goals to further incorporate
    shorebird needs. Work with joint venture agencies and their various
    programs to implement shorebird-friendly projects on the ground.

-   Adopt new management strategies proven to be valuable.

    *Agricultural Fields.* With the exception of rice, few data are
    available on the acreage of irrigated or flooded agricultural lands
    in the Central Valley at any specific time, although this habitat is
    very extensive seasonally. In January 1994, about 142,000 acres of
    rice were flooded in the Central Valley, primarily in the Sacramento
    Valley (Table 2). Flooded agricultural fields support large numbers
    of shorebirds, particularly in winter, and the amount of flooded
    habitat can vary greatly both seasonally and among years of varying
    precipitation. Rice fields alone can hold 20% to 30% of valleywide
    shorebird totals (Shuford et al. 1998). Species that forage
    extensively in flooded fields are the Killdeer, Greater Yellowlegs,
    small sandpipers (especially Dunlin in winter), and Long-billed
    Dowitcher. The Black-bellied Plover, Killdeer, Whimbrel (mainly in
    spring), and Long-billed Curlew use both flooded and drier upland
    fields for foraging. By contrast, the Mountain Plover almost
    exclusively uses dry, very open upland habitats, such as heavily
    grazed pastures, plowed fields, and alkali flats (Knopf and Rupert
    1995).

    To meet a legislative mandate to reduce air pollution in the
    Sacramento Valley, farmers recently have begun winter flooding of
    fields as an alternative to burning to dispose of rice stubble.
    Although the increase in winter-flooded habitat so far has been
    modest (Spell et al. 1995), it is expected to expand from the
    current level of 140,000 acres to 190,000 to 200,000 acres (F. Reid
    pers. comm.). This change in land use has prompted new research on
    the effects of various harvest, flooding, and rice straw
    manipulation techniques. Elphick and Oring (1998) studied the effect
    of various water depth and straw treatments on waterbird use of
    Sacramento Valley rice fields in winter. Median water depths of
    flooded rice fields used by shorebirds in winter were about 1 to 5
    inches, whereas in early winter median depths of most fields were
    greater than 8 inches. The Killdeer, Least Sandpiper, Dunlin, and
    Long-billed Dowitcher occurred in highest densities in fields in
    which straw had been incorporated in the soil prior to flooding,
    though this may have been due to shallower water in incorporated
    fields. By contrast, the American Avocet was most abundant in fields
    that had no treatment except flooding. These authors recommended
    that reducing water depths in rice fields in the early part of the
    winter would lead to use by a wider variety of species while also
    lowering water costs. Results of across habitat measures of food
    abundance, perceived predation threat, foraging performance, and
    time allocation suggest that flooded rice fields may provide
    equivalent foraging habitat to semi-natural wetlands and, because of
    reduced predation threat, may be safer habitat for waterbirds
    (Elphick 1998).

    Elphick (1998) also found shorebirds responding differentially to
    features in the landscape at various scales. Shorebird densities in
    rice fields were positively related to the proportion of the
    surrounding landscape at the 2 km (1.2 mi) scale that was a wildlife
    refuge, semi-natural wetland, or both. Conversely, shorebird
    densities were negatively correlated with an abundance of flooded
    agricultural land at the 10 km (6.2 mi) scale.

    Day and Colwell (1998) also studied the effects of harvest method,
    post-harvest treatment of straw, and extent of flooding on waterbird
    use of Sacramento Valley rice fields in winter. Shorebirds occurred
    primarily in conventionally-harvested (vs. "stripped") fields that
    were puddled or flooded; species richness of waterbirds did not
    differ among straw treatments.

    Priority conservation actions for agricultural lands of the Central
    Valley are to:

-   Promote conservation easements and agricultural (vs. wetland)
    easements , protecting lands of both high and low productivity.

-   Promote harvesting of rice fields by conventional methods (or add
    secondary efforts to cut stubble) and promote winter flooding to
    water depths suitable for a high diversity of waterbirds, including
    shorebirds.

-   Increase the acreage of flooded rice in winter and reduce water
    depths in rice fields early in the winter relative to current
    practices.

-   Curtail loss and restore habitats, such as vernal pool rangelands,
    that currently are diminishing at a rapid rate.

    *Agricultural Evaporation Ponds.* The approximately 5409 acres of
    very saline agricultural evaporation ponds in the Tulare Basin of
    the southern San Joaquin Valley (Table 2) can support high densities
    of shorebirds seasonally. In fall, highest numbers of shorebirds in
    the Central Valley can occur in these evaporation ponds (Shuford et
    al. 1998). In that season, key species foraging in these ponds
    include the Black-necked Stilt, American Avocet, small sandpipers
    (Western and Least sandpipers), and Wilson's and Red-necked
    phalaropes. Shorebird numbers in these ponds appear to be declining
    because of management efforts to limit their use and thereby reduce
    the risk of exposure to concentrated contaminants, such as selenium.
    Pond owners have sought to reduce the risk to wildlife of these
    ponds by hazing, physically altering ponds to make them less
    attractive, and creating nearby uncontaminated wetlands as
    alternative habitat.

    Priority conservation actions for agricultural evaporation ponds in
    the Central Valley are to:

-   Continue to devise strategies to reduce shorebird use on
    contaminated evaporation ponds while increasing shorebird use of
    nearby mitigation wetlands.

-   Ensure that alternative habitats created provide suitable conditions
    for species, such as the Snowy Plover, that favor shallow saline
    water and alkali flats.

    *Sewage Ponds.* A minimum of 8413 acres of sewage ponds are present
    in the Central Valley, with the greatest extent of this habitat
    occurring in the San Joaquin and Tulare basins (Table 2). Although
    sewage ponds hold a relatively small percentage of the valleywide
    shorebird total at any season, particular pond systems periodically
    may host large numbers of shorebirds. Sewage ponds also may serve as
    important roosting sites for species, such as the Black-bellied
    Plover, that forage in nearby fields.

    Although various management actions potentially could increase the
    use of sewage ponds by shorebirds, pre-implementation studies are
    needed first to determine if transmission of diseases or
    concentrations of toxic substances pose substantial threats to
    shorebirds or other species of wildlife using these ponds.

    *Vernal Pool Rangelands.* Holland (1998) mapped the distribution of
    grassland-vernal pool complexes in California and found them
    scattered widely around the perimeter of the Central Valley and in a
    swath in the basin lands along the valley trough. A total of 999,319
    acres of this habitat occurred in counties with valley floor
    terrain; roughly 31% was in the Sacramento Valley, 14% in the Delta,
    47% in the San Joaquin Basin, and 8% in the Tulare Basin. Although
    these figures include both vernal pools and surrounding grasslands,
    nevertheless the total acreage of wetlands represented by vernal
    pools valleywide is impressive. Although there has been considerable
    historical loss of vernal pool habitat, the extent of this loss is
    unknown.

    Silveira (1998) described the importance of vernal pools to birds,
    but use of these pools by shorebirds has been poorly studied.
    Shuford et al's (1998) study of shorebird use of Central Valley
    habitats did not find especially large numbers of shorebirds in
    vernal pools, though their surveys did not include large areas of
    vernal pool rangelands on the periphery of the valley (D.
    Shuford, G. Page pers. obs.). Although used by a variety of
    shorebirds, vernal pools probably are particularly important to
    species, such as the Greater Yellowlegs, that occur singly or in
    small loose flocks. Feldheim et al. (1999) conducted a two-year
    study of shorebird habitat use at Sacramento NWR in the Sacramento
    Valley. Although vernal pools comprised less than 2% of the refuge's
    total available wetland habitat, they held the highest shorebird
    densities, and more species preferred vernal pools than other
    wetland types.

    Priority conservation actions for vernal pool landscapes in the
    Central Valley are to (Silveira 1998):

-   Identify large intact vernal pool complexes and develop conservation
    plans for these complexes and surrounding vernal pool landscapes.

-   Develop a vernal pool conservation team.

-   Create patterns of land use in and around vernal pool landscapes
    consistent with agriculture and open space conservation.

-   Develop public private partnerships and obtain (and monitor)
    conservation easements on large private cattle ranches via Land and
    Water Conservation Funds.

    **Monitoring Priorities**

    Monitoring shorebird populations in the Central Valley will be very
    challenging because of the large geographic size of the area and the
    great seasonal and annual variation in extent of habitat,
    particularly as influenced by cycles of drought and flood. With this
    in mind, the priorities for monitoring for the subregion are to:

-   Devise a long-term monitoring scheme to detect overall trends in
    shorebird abundance and habitat use in the Central Valley; ensure
    repeatability and reliability of results. Such a scheme needs
    specific protocols, including census methodology, periodicity of
    surveys, procedures to deal with fluctuations in habitat
    availability, etc.

-   Devise long-term monitoring protocols for restoration and
    enhancement projects to ensure they meet goals of shorebird use.
    Such efforts should recognize that landscape level effects, such as
    the extremes of drought and flooding on nearby and/or widely
    distributed agricultural lands, may override beneficial wetland
    practices in certain years.

-   Establish long-term monitoring schemes for sensitive shorebird
    species -- Mountain Plover, Snowy Plover, Long-billed Curlew -- in
    the Central Valley.

-   Conduct valleywide surveys of populations of breeding shorebirds in
    years of varying environmental conditions to establish baseline data
    useful in establishing recommendations for actions to increase these
    populations.

-   Monitor shorebird habitats at the landscape level using GIS
    technology.

    **Research Priorities**

    Research priorities for the Central Valley are to:

-   Identify limiting factors and specific habitat needs of shorebirds.

-   Obtain information on the diets of shorebirds at different seasons
    and in various habitats.

-   Determine how various drawdown regimes influence the production of
    invertebrates and their availability to shorebirds.

-   Investigate how shorebirds move within and among wetland complexes.
    Determine the needs of shorebirds for roosting habitat.

-   Quantitatively monitor the responses of shorebirds to various
    management strategies.

-   Assess fidelity and survivorship of shorebirds using the Central
    Valley.

-   Examine the potential effects on shorebirds of biosolids (sewage
    sludge) spread on agricultural fields as a fertilizer.

-   Study shorebird use of grazed habitats, such as irrigated pastures
    and seasonally grazed wetlands, as has been done for coastal
    pastures (Colwell and Dodd 1995).

-   Conduct broadscale surveys of vernal pools to determine their
    importance to shorebirds.

-   Investigate whether concerns over mosquito control, vegetation
    management, and water costs can be overcome while providing shallow
    water habitat in summer (Jul-Aug) for autumn migrant shorebirds.

    **Education Priorities**

    Priority education goals for the Central Valley are to:

-   Educate landowners and the public of the direct economic benefit of
    ecotourism and wetland festivals (e.g., Wild on Wetlands Weekend)
    and the consequent need to manage for a diversity of species,
    including shorebirds. Also, illustrate how ecotourism can help fend
    off urban encroachment on wetlands.

-   Inform private landowners and public resource managers how to
    incorporate shorebird management strategies into existing wetland
    management schemes, thereby blending practices for waterfowl and
    shorebirds. Emphasize that management for shorebirds can benefit
    waterfowl. For example, certain dabbling ducks prefer to feed in
    shallow flooded marshes, drawdowns increase marsh productivity, and
    seasonally flooded wetlands receive greater waterfowl use in winter
    than permanent ponds.

-   Work with agricultural interests to promote management that benefits
    both shorebirds and crop production. Work with agricultural
    extension specialists to educate landowners regarding how minor
    changes in farming practices may provide large benefits to
    shorebirds and other wildlife.

**Implementation and Coordination**

Conservation of shorebirds in the Central Valley will of necessity
involve a host of public and private agencies and individuals to ensure
its success. It will be particularly important to coordinate with
already established collaborative efforts, such as the Central Valley
Habitat Joint Venture of the North American Waterfowl Management Plan,
Partners in Flight, the California Riparian Joint Venture, and other
natural resource programs like Partners for Wildlife, and to integrate
with other formative efforts, such as the Colonial Waterbird
Conservation Plan and the North American Bird Conservation Initiative.
Coordination already exists at the local level at wetlands complexes
such at the Grasslands Ecological Area in the San Joaquin Valley. There
shorebird concerns can be brought to their Habitat Coordination
Committee, which has representatives from U.S. Fish and Wildlife
Service, California Department of Fish and Game, Grasslands Water
District, Grasslands Resource Conservation District, and private
landowners.

Various wetland incentive and technical assistance programs offered by
federal, state, and private agencies are the best means to coordinate
drawdowns and implement integrated management practices on private lands
(Isola 1998).

### CONTRIBUTORS

Preparation of this document was greatly facilitated by the combined
knowledge of the following individuals who kindly shared their expertise
via meetings, personal communications, and the publication of their
research results.

\[The final draft of this document will include complete addresses,
phone numbers, and email address for all contributors.\]

**Northern California Coast**

Sarah Allen National Park Service

Mark Colwell Humboldt State University

Peter Connors Bodega Marine Laboratory

Kevin Hunting California Department of Fish and Game

John Kelly Audubon Canyon Ranch

Gary Page Point Reyes Bird Observatory

David Shuford Point Reyes Bird Observatory

Nils Warnock Point Reyes Bird Observatory

**San Francisco Bay**

Joy Albertson U.S. Fish and Wildlife Service

Dennis Becker California Department of Fish and Game

Doug Bell San Francisco Bay Bird Observatory

Joelle Buffa U.S. Fish and Wildlife Service

Janet Hanson San Francisco Bay Bird Observatory

Kevin Hunting California Department of Fish and Game

Gary Page Point Reyes Bird Observatory

Nils Warnock Point Reyes Bird Observatory

Carl Wilcox California Department of Fish and Game

Larry Wyckoff California Department of Fish and Game

**Southern California Coast**

John Bradley U.S. Fish and Wildlife Service

Erick Burres California Department of Fish and Game

Brian Collins U.S. Fish and Wildlife Service

Sarah Connors Moss Landing Marine Laboratory

Tim Dillingham California Department of Fish and Game

Jack Fancher U.S. Fish and Wildlife Service

Loren Hays U.S. Fish and Wildlife Service

Katie Kropp State Water Resources Control Board

Kevin Lafferty University of California

Melissa Mailander San Diego Unified Port District

Kimberly Mc Kee-Lewis California Department of Fish and Game

Robin Stribley City of San Diego

**Central Valley**

Mark Ackerman Cosumnes River Preserve

Jack Allen Kern National Wildlife Refuge

Doug Barnum USGS Biological Resource Division

John A. Beam Los Banos Wildlife Area

Dan Blake Upper Butte Basin Wildlife Area

Mike Brady Stone Lakes National Wildlife Refuge

Holden Brink Cosumnes River Preserve

Steve Cordes Upper Butte Basin Wildlife Area

Chris Elphick Dept. Ecol. and Evol. Biology, Univ. Conn.

David Feliz Yolo Bypass Wildlife Area

Robert Hansen Hansen Biological Consulting

Dave Hardt Kern National Wildlife Refuge

Bob Herkert California Rice Promotion Board

Robert Huddleston Mendota Wildlife Area

Craig Isola Sacramento National Wildlife Refuge complex

Jennifer Isola Sacramento National Wildlife Refuge complex

Dean Kwasny Grasslands Water District

Henry Lomeli District Biologist/Butte Co., Calif. Dept. Fish Game

Greg Mensik Sacramento National Wildlife Refuge complex

Gary Page Point Reyes Bird Observatory

Tim Poole Wetland Consultant

Fritz Reid Ducks Unlimited, Inc.

Jeff Seay H.T. Harvey and Associates

Dave Shuford Point Reyes Bird Observatory

Joe Silveira Sacramento National Wildlife Refuge complex

Oriane Williams Taft Forest and Range Ecosystem Sci. Ctr., Corvallis, OR

Ron Thompson Gray Lodge Wildlife Area

Mike Wolder Sacramento National Wildlife Refuge complex

Dennis Woolington San Luis National Wildlife Refuge complex

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**APPENDIX: LIST OF COMMON AND SCIENTIFIC NAMES OF SHOREBIRD SPECIES
CITED IN THE TEXT**

Black-bellied Plover *(Pluvialis squatarola)*

American Golden-Plover *(Pluvialis dominica)*

Pacific Golden-Plover *(Pluvialis fulva)*

Snowy Plover *(Charadrius alexandrinus)*

Semipalmated Plover *(Charadrius semipalmatus)*

Killdeer *(Charadrius vociferus)*

Mountain Plover *(Charadrius montanus)*

Black Oystercatcher *(Haematopus bachmani)*

Black-necked Stilt *(Himantopus mexicanus)*

American Avocet *(Recurvirostra americana)*

Greater Yellowlegs *(Tringa melanoleuca)*

Lesser Yellowlegs *(Tringa flavipes)*

Solitary Sandpiper *(Tringa solitaria)*

Willet *(Catoptrophorus semipalmatus)*

Wandering Tattler *(Heteroscelus incanus)*

Spotted Sandpiper *(Actitis macularia)*

Whimbrel *(Numenius phaeopus)*

Long-billed Curlew *(Numenius americanus)*

Marbled Godwit *(Limosa fedoa)*

Ruddy Turnstone *(Arenaria interpres)*

Black Turnstone *(Arenaria melanocephala)*

Surfbird *(Aphriza virgata)*

Red Knot *(Calidris canutus)*

Sanderling *(Calidris alba)*

Semipalmated Sandpiper *(Calidris pusilla)*

Western Sandpiper *(Calidris mauri)*

Least Sandpiper *(Calidris minutilla)*

Baird's Sandpiper *(Calidris bairdii)*

Pectoral Sandpiper *(Calidris melanotos)*

Rock Sandpiper *(Calidris ptilocnemis)*

Dunlin *(Calidris alpina)*

Short-billed Dowitcher *(Limnodromus griseus)*

Long-billed Dowitcher *(Limnodromus scolopaceus)*

Common Snipe *(Gallinago gallinago)*

Wilson's Phalarope *(Phalaropus tricolor)*

Red-necked Phalarope *(Phalaropus lobatus)*

Red Phalarope *(Phalaropus fulicaria)*