Ellicott Slough National Wildlife Refuge Final Comprehensive Conservation Plan and Environmental Assessment

              U.S. Fish & Wildlife Service
Ellicott Slough
National Wildlife Refuge
Final Comprehensive Conservation Plan
and Environmental Assessment
September 2010
Disclaimer
CCPs provide long term guidance for management decisions and set forth goals, objectives,
and strategies needed to accomplish refuge purposes and identify the Service’s best estimate
of future needs. These plans detail program planning levels that are sometimes substantially
above current budget allocations and, as such, are primarily for Service strategic planning
and program prioritization purposes. The plans do not constitute a commitment for staffing
increases, operational and maintenance increases, or funding for future land acquisition.
Ellicott Slough
National Wildlife Refuge
Final Comprehensive Conservation Plan
and Final Environmental Assessment
Prepared By
US Fish and Wildlife Service
San Francisco Bay National Wildlife Refuge Complex
9500 Thornton Avenue
Newark, California 94560
and
Pacific Southwest Region
2800 Cottage Way, W-1832
Sacramento, California 95825
September 2010
Ellicott Slough NWR - Final Comprehensive Conservation Plan iii
Table of Contents
Abbreviations and Acronyms..........................................................................................................................vi
Chapter 1. Introduction and Background.............................................................................................. 1
1.1 Purpose and Need for this CCP ............................................................................................. 1
1.2 The U.S. Fish and Wildlife Service and the National Wildlife Refuge System ............... 2
1.2.1 U.S. Fish and Wildlife Service...................................................................................... 2
1.2.2 The National Wildlife Refuge System......................................................................... 2
1.2.3 National Wildlife Refuge System Mission and Goals................................................ 2
1.3 Legal and Policy Guidance....................................................................................................... 2
1.3.1 The Improvement Act ................................................................................................. 3
1.3.2 Refuge System Policies ................................................................................................. 3
1.4 San Francisco Bay National Wildlife Refuge Complex........................................................ 3
1.5 Ellicott Slough National Wildlife Refuge............................................................................... 3
1.5.1 Location.......................................................................................................................... 3
1.5.2 Refuge Setting................................................................................................................ 3
1.5.3 History of Refuge Establishment and Acquisition.................................................... 4
1.5.4 Refuge Purposes ............................................................................................................ 7
1.5.5 Ecosystem Context and Related Projects.................................................................. 8
1.5.6 Conservation Priorities and Initiatives....................................................................... 8
1.5.7 Adaptive Management................................................................................................... 8
Chapter 2. The Comprehensive Conservation Planning Process..................................................... 9
2.1 The Planning Process: How the CCP was Developed......................................................... 9
2.1.1 Preplanning.................................................................................................................... 9
2.1.2 Planning Hierarchy........................................................................................................ 9
2.1.3 The Core Planning Team............................................................................................... 10
2.1.4 The Extended Planning Team...................................................................................... 10
2.2 Public Involvement in Planning............................................................................................... 11
2.2.1 Issues, Concerns, and Opportunities Identified through Scoping........................... 11
2.2.2 Additional Management Issues Identified by Staff through Scoping..................... 11
2.3 Development of Refuge Vision................................................................................................ 11
2.4 Development of Refuge Goals, Objectives and Strategies................................................... 12
2.4.1 Goals ............................................................................................................................... 12
2.4.2 Objectives, Rationale, and Strategies.......................................................................... 12
2.5 Development of Alternatives................................................................................................... 12
2.6 Selection of the Refuge Proposed Action............................................................................... 13
2.7 Plan Implementation................................................................................................................ 13
Chapter 3. Refuge and Resource Description....................................................................................... 15
3.1 Geographic/Ecosystem Setting............................................................................................... 15
3.2 Description by Refuge Unit..................................................................................................... 15
iv Ellicott Slough NWR - Final Comprehensive Conservation Plan
3.2.1 Ellicott Unit..................................................................................................................... 15
3.2.2 Calabasas Unit................................................................................................................ 16
3.2.3 Harkins Slough Unit...................................................................................................... 16
3.2.4 Buena Vista..................................................................................................................... 17
3.3 Physical Resources.................................................................................................................... 17
3.3.1 Climate and Air Quality................................................................................................. 17
3.3.2 Climate Change and Greenhouse Gas Emissions ..................................................... 18
3.3.3 Climate Change Regulation.......................................................................................... 20
3.3.4 Topography..................................................................................................................... 20
3.3.5 Geology, Soils, and Hydrology....................................................................................... 20
3.3.6 Water Supply and Water Quality.................................................................................. 22
3.3.7 Hazardous Materials and Contaminants..................................................................... 24
3.4 Biological Resources................................................................................................................. 30
3.4.1 Vegetation....................................................................................................................... 30
3.4.2 Wildlife............................................................................................................................ 34
3.5 Cultural Resources.................................................................................................................... 40
3.5.1 Social and Economic Environment.............................................................................. 40
3.5.2 Demographics................................................................................................................. 41
3.5.3 Traffic and Public Access............................................................................................... 41
3.5.4 Local Economy and Employment................................................................................ 41
3.5.5 Environmental Justice................................................................................................... 41
Chapter 4. Current Refuge Management and Programs................................................................... 43
4.1 Land Management ................................................................................................................... 43
4.2 Water Management................................................................................................................... 43
4.3 Wildlife Management................................................................................................................ 43
4.3.1 Mosquito Population Management............................................................................... 44
4.4 Fire Prevention and Hazard Reduction................................................................................. 44
4.5 Law Enforcement and Resource Protection......................................................................... 45
4.6 Cultural Resource Management............................................................................................. 45
4.7 Facilities Maintenance.............................................................................................................. 45
4.8 Safety.......................................................................................................................................... 46
4.9 Volunteers and Partners........................................................................................................... 46
4.10 Visitor Programs....................................................................................................................... 46
4.11 Environmental Education and Interpretation...................................................................... 46
4.12 Fishing and Hunting................................................................................................................. 47
4.13 Wildlife Observation and Photography................................................................................... 47
4.14 Outreach.................................................................................................................................... 47
Chapter 5. Management Direction.......................................................................................................... 49
5.1 Ellicott Slough NWR Vision Statement................................................................................. 49
5.2 Refuge Management Goals, Objectives, and Strategies...................................................... 49
Chapter 6. Plan Implementation.............................................................................................................. 61
6.1 Funding and Staffing................................................................................................................. 61
6.2 Step-Down Management Plans............................................................................................... 61
6.3 Compatibility Determination................................................................................................... 63
Ellicott Slough NWR - Final Comprehensive Conservation Plan v
Appendix A - References
Appendix B - Glossary of Terms
Appendix C - Final Environmental Assessment and Finding of No Significant Impact
Appendix D - Plant List
Appendix E - Section 7, Endangered Species Act Compliance
Appendix F - Wildlife List
Appendix G - Compatibility Determinations
Appendix H - Wilderness Inventory
Appendix I - List of Preparers
Appendix J - Public Involvement and Responses to Comments on the July 2010 Draft
Comprehensive Conservation Plan and Environmental Assessment (Draft CCP/EA)
Appendix K - Other Environmental Compliance
Appendices
Figure 1. San Francisco Bay NWR Complex Map..................................................................................... 5
Figure 2. Ellicott Slough NWR Location Map............................................................................................ 6
Figure 3. The CCP Process Diagram..........................................................................................................10
Figure 4. Soil Types on the Ellicott Slough NWR.....................................................................................21
Figure 5. Watsonville Slough System..........................................................................................................23
Figure 6. Vegetation – Ellicott Unit.............................................................................................................26
Figure 7. Vegetation – Calabasas Unit........................................................................................................27
Figure 8. Vegetation – Harkins Slough Unit..............................................................................................28
Figure 9. Vegetation – Buena Vista Property.............................................................................................29
Figure 10. Visitor Services at Ellicott Slough NWR ..................................................................................59
Figures
Tables
Table 1. Key policies related to management of National Wildlife Refuges......................................... 4
Table 2. Pollutant measures for North Central Coast Air Basin - 2006................................................18
Table 3. Ellicott Slough NWR - Acreages of habitat types by unit.......................................................25
Table 4. Population counts for robust spineflower on Buena Vista........................................................34
Table 5. Santa Cruz long-toed salamander subpopulation complexes..................................................34
Table 6. Estimated initial capital outlay to fully implement the CCP...................................................62
Table 7. Estimated annual cost to fully implement the CCP ...............................................................63
6.4 Compliance Requirements....................................................................................................... 64
6.5 Partnership Opportunities....................................................................................................... 64
6.6 Monitoring and Evaluation...................................................................................................... 64
6.7 Adaptive Management.............................................................................................................. 64
6.8 Plan Amendment and Revision............................................................................................... 65
vi Ellicott Slough NWR - Final Comprehensive Conservation Plan
Complex  San Francisco Bay NWR Complex
Ellicott Slough NWR  Ellicott Slough National Wildlife Refuge (Refuge)
Improvement Act  National Wildlife Refuge System Improvement Act of 1997 (or 1997
Improvement Act)
Plan  Comprehensive Conservation Plan (CCP)
Refuge System  The National Wildlife Refuge System (NWRS)
Service  U.S. Fish and Wildlife Service (USFWS)
ATV  All-terrain vehicle
BD  Batrachochytrium dendrobatidis
BIDEH  Biological Integrity, Diversity and Environmental Health
(601 FW3)
CAL FIRE  California Department of Forestry and Fire Protection
CCC  California Conservation Corps
CCP  Comprehensive Conservation Plan (CCP)
CCAMP  Central Coast Ambient Monitoring Program
CCRWQCB  Central Coast Regional Water Quality Control Board
CDFG  California Department of Fish and Game
CEQA  California Environmental Quality Act
CNDDB  California Natural Diversity Database
CNPS  California Native Plant Society
CRLF  California red-legged frog
CTS  California tiger salamander
EA  Environmental Assessment
EO  Executive Order
EPA  Environmental Protection Agency
ESA  Endangered Species Act of 1973, as amended
FMP  Fire Management Plan
FSA  Farm Service Agency
FTE  Full Time Employee
GHG  greenhouse gas
GIS  Geographic Information System
IPCC  Intergovernmental Panel on Climate Change
Abbreviations and Acronyms
Ellicott Slough NWR - Final Comprehensive Conservation Plan vii
KOA  Kampgrounds of America
MBUAPCD  Monterey Bay Unified Air Pollution Control District
MMT  million metric tons
MOU  Memorandum of Understanding
NEPA  National Environmental Policy Act
NRCS  Natural Resource Conservation Service
NWR  National Wildlife Refuge
NWRS  National Wildlife Refuge System (Refuge System)
PG&E  Pacific Gas and Electric
PUP  Pesticide Use Proposal
RONS  Refuge Operating Needs System
SCCMCV  Santa Cruz County Mosquito and Vector Control
SCLTS  Santa Cruz long-toed salamander
SHPO  (California) State Historic Preservation Office
SLAMM  Sea-level Affecting Marshes Model
SUP  Special Use Permit
TPL  Trust for Public Land
USFWS  U.S. Fish and Wildlife Service (Service)
USGS  U.S. Geological Survey
VOC  volatile organic compounds
WCB  Wildlife Conservation Board
WNV  West Nile Virus
WUI  Wildland Urban Interface
Ellicott Slough NWR - Final Comprehensive Conservation Plan 1
The U.S. Fish and Wildlife Service (Service)
manages the Ellicott Slough National Wildlife
Refuge (Refuge, Ellicott Slough NWR) located in
Santa Cruz County within the Monterey Bay area,
California. Established in 1975, the Refuge provides
vital habitat for the endangered Santa Cruz long-toed
salamander (Ambystoma macrodactylum croceum),
the threatened California red-legged frog (Rana
aurora draytonii), the threatened California tiger
salamander (Ambystoma californiense), and the
endangered robust spineflower (Chorizanthe robusta).
The Service prepared this Comprehensive
Conservation Plan (CCP, Plan) to guide Refuge
management for the next 15 years. The CCP
provides a description of the desired future
conditions and long-range guidance to accomplish
the purposes for which the Refuge was established.
The CCP and accompanying environmental
assessment (EA) address Service legal mandates,
policies, goals, and National Environmental Policy
Act (NEPA) compliance.
The CCP is divided into six chapters: Chapter 1,
Introduction and Background; Chapter 2, The
Comprehensive Conservation Planning Process;
Chapter 3, Refuge and Resource Description;
Chapter 4, Current Refuge Management and
Programs; Chapter 5, Management Direction; and
Chapter 6, Plan Implementation.
1.1 Purpose and Need for this CCP
No formal management plan currently exists for
the Refuge. The National Wildlife Refuge System
(Refuge System, NWRS) Improvement Act of 1997
(16 United States Code [USC] 668dd-668ee) (1997
Improvement Act) requires that all refuges be
managed in accordance with an approved CCP by
2012. Under the 1997 Improvement Act, the Refuge
System is to be consistently directed and managed
to fulfill the specific purpose(s) for which each
refuge was established as well as the Refuge System
Mission. The planning process helps the Service
achieve the refuge purposes and the Refuge System
mission by identifying specific goals, objectives,
and strategies to implement on each refuge. The
purposes of this CCP are as follows:
■■ Provide a clear statement of direction for the
management of the Refuge during the lifetime
of the CCP.
■■ Provide long-term continuity in Refuge
management.
■■ Communicate the Service’s management
priorities for the Refuge to its neighbors and
the public.
■■ Provide an opportunity for the public to help
shape the future management of the Refuge.
■■ Ensure that management programs on the
Refuge are consistent with the legal and
policy mandates for the Refuge System and
the purpose of the Refuge as set forth in
establishing documentation.
■■ Ensure that management of the Refuge is, to
the extent practicable, consistent with Federal,
state, and local plans.
Chapter 1. Introduction and Background
Ellicott Slough NWR entrance sign. Photo: USFWS
Chapter 1
2 Ellicott Slough NWR - Final Comprehensive Conservation Plan
■■ Provide a basis for budget requests to support
the Refuge’s needs for staffing, operations,
maintenance, and capital improvements.
■■ Evaluate existing and proposed uses on each of
the Refuges to ensure that they are compatible
with the Refuge purpose(s); the Refuge Sys-tem
mission; and the maintenance of biological
integrity, biodiversity, and environmental health
(or BIDEH).
1.2 The U.S. Fish and Wildlife
Service and the National Wildlife
Refuge System
1.2.1 U.S. Fish and Wildlife Service
The Service is the primary Federal agency
responsible for conserving, protecting, and enhancing
the Nation’s fish, wildlife, and plant populations
and their habitats for the continuing benefit of the
American people. Although the Service shares
this responsibility with other Federal, tribal, state,
local, and private entities, the Service has specific
responsibilities for migratory birds, threatened and
endangered species, interjurisdictional fish, and
certain marine mammals. These are referred to as
Federal Trust Species. The Service also manages
the National Wildlife Refuge System and National
Fish Hatcheries, enforces Federal wildlife laws
and international treaties related to importing and
exporting wildlife, assists state fish and wildlife
programs, and helps other countries develop wildlife
conservation programs.
1.2.2 The National Wildlife Refuge System
The National Wildlife Refuge System (Refuge
System) is the world’s largest collection of
lands specifically managed for fish and wildlife
conservation. Unlike other Federal lands that
are managed under a multiple-use mandate (e.g.,
National Forests and lands administered by the U.S.
Bureau of Land Management, the Refuge System
is managed primarily for the benefit of fish, wildlife,
and plant resources and their habitats. The Refuge
System consists of more than 551 units that provide
more than 150 million acres of important habitat
nationwide for native plants and many species of
mammals, birds, and fish, including threatened and
endangered species.
1.2.3 National Wildlife Refuge System
Mission and Goals
The mission of the Refuge System is “to administer
a national network of lands and waters for the
conservation, management and, where appropriate,
restoration of the fish, wildlife and plant resources
and their habitats within the United States for
the benefit of present and future generations of
Americans” (1997 Improvement Act).
The goals of the Refuge System are:
a. Conserve a diversity of fish, wildlife, and
plants and their habitats, including species
that are endangered or threatened with
becoming endangered.
b. Develop and maintain a network of habitats
for migratory birds, anadromous and
interjurisdictional fish, and marine mammal
populations that is strategically distributed and
carefully managed to meet important life history
needs of these species across their ranges.
c. Conserve those ecosystems; plant communities;
wetlands of national or international signifi-cance;
and landscapes and seascapes that are
unique, rare, declining, or underrepresented in
existing protection efforts.
d. Provide and enhance opportunities
to participate in compatible wildlife-dependent
recreation (hunting, fishing,
wildlife observation, and photography, and
environmental education and interpretation).
e. Foster understanding and instill appreciation
of the diversity and interconnectedness of fish,
wildlife, and plants and their habitats.
1.3 Legal and Policy Guidance
Refuges are guided by the purposes of the individual
refuge, the mission and goals of the Refuge System,
Service policy, laws, and international treaties.
Relevant guidance includes the Refuge Recreation
Act of 1962, the 1997 Improvement Act, and selected
portions of the Code of Federal Regulations and the
U.S. Fish and Wildlife Service Manual. Refuges
are also governed by a variety of other Federal
laws, Executive orders (EOs), treaties, interstate
compacts, regulations, and policies pertaining to the
conservation and protection of natural and cultural
resources (see Service Manual 602 FW 1 [1.3]).
Ellicott Slough NWR - Final Comprehensive Conservation Plan 3
1.3.1 The Improvement Act
The 1997 Improvement Act, which amends the
National Wildlife Refuge System Administration
Act of 1966, serves as an “organic” act for the
Refuge System and provides comprehensive
legislation describing how the Refuge System
should be managed and used by the public. The
1997 Improvement Act’s main components include
the following.
■■ A strong and singular wildlife conservation
mission for the Refuge System
■■ A recognition of six priority public uses
of the Refuge System (hunting, fishing,
wildlife observation and photography, and
environmental education and interpretation)
■■ A requirement that the Secretary of the Interior
maintain the biological integrity, diversity, and
environmental health of Refuge System lands
■■ A new process for determining compatible uses
on refuges
■■ A requirement for preparing a Comprehensive
Conservation Plan for each refuge by 2012
1.3.2 Refuge System Policies
Refuge System policies are found in the land
use management series (600) of the U.S. Fish
and Wildlife Service Manual. These policies are
available online at www.fws.gov/policy/manuals.
Table 1 provides brief descriptions of key policies
related to refuge management and use.
1.4 San Francisco Bay National
Wildlife Refuge Complex
With the support of citizens and public officials,
seven refuges have been established in the San
Francisco and Monterey Bay Areas: Farallon NWR
(1909), Salinas River NWR (1973), San Pablo Bay
NWR (1974), San Francisco Bay NWR (1974),
Ellicott Slough NWR (1975), Antioch Dunes NWR
(1980), and Marin Islands NWR (1992). These
seven refuges, stretching from Monterey Bay to
the Sacramento–San Joaquin River Delta, were
combined to create the San Francisco Bay NWR
Complex (Complex) (Figure 1). These refuges
provide a variety of critical habitat, food, and shelter
for native plants and animals such as threatened
and endangered species, species of special concern,
waterfowl, and many others. Unlike refuges in
remote locations, each of these seven refuges shares
the task of implementing wildlife conservation
objectives while addressing human needs in a
highly urbanized environment. The Complex is
administered from a headquarters office located on
the Don Edwards San Francisco Bay NWR, near
the city of Fremont.
1.5 Ellicott Slough National
Wildlife Refuge
1.5.1 Location
The Ellicott Slough National Wildlife Refuge
(Refuge) is located on the southern coast of Santa
Cruz County, approximately four miles west of the
city of Watsonville. Santa Cruz County is part of the
larger Monterey Bay area and is heavily influenced
by marine conditions of the Pacific Ocean. This
area is small but diverse with mountains, foothills,
valleys, and marine scenery. The soil is productive,
making the area an important agricultural base.
Residential and agricultural development surrounds
the Refuge.
1.5.2 Refuge Setting
Present-day Santa Cruz and Watsonville were
explored in 1769 by an expedition led by Don Caspar
de Portola. Settlers came with the founding of the
Santa Cruz Mission in September 1791 (Watkins
1925). Farming was first practiced near the Mission
and even continues today. Wheat, corn, and barley
were the principal crops, but fruit orchards also
existed. Raising livestock was also important.
Logging began in 1832, and numerous mills were
built to utilize the local timber. California was
acquired from Mexico by the United States in
1846. Santa Cruz County was formally organized
in 1850. In 1851, farmers settled into Pajaro Valley.
In 1858, commercial apple orchards were started,
and by 1910, there were a million trees on 14,000
acres. Other crops that were grown from the late
1800s through the 1900s included prunes, hops,
sugar beets, strawberries, and lettuce. The farming
industry was stimulated greatly when the railroad
came into the Pajaro Valley in 1870 (Martin 1911).
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4 Ellicott Slough NWR - Final Comprehensive Conservation Plan
1.5.3 History of Refuge Establishment
and Acquisition
In 1971, the original owner of the Ellicott Slough
area intended to rezone the area to develop it into a
trailer park. However, the proposal was denied by
the Santa Cruz County commissioners because at
the time, the parcel contained one of only two known
active breeding ponds for the Santa Cruz long-toed
salamander (USFWS 1975). The California
Department of Fish and Game (CDFG) later
acquired the property and some adjacent upland
in 1973 and designated the 30-acre acquisition as
a State Ecological Reserve. During that time,
salamanders were found in significant numbers
in chaparral and oak woodland up to at least a
quarter mile from the breeding pond (USFWS
1975). In 1975, the Service acquired additional
adjacent upland habitat to protect the salamander’s
terrestrial lifecycle needs and established Ellicott
Slough NWR. Beginning with 41 acres in 1975, 87
acres were added the following year to make up the
128-acre Ellicott Unit. The 30-acre State Ecological
Reserve is included in the Ellicott Unit and is
managed by the Refuge under a Memorandum
of Understanding (MOU) with the CDFG. Two
easements are also associated with the Ellicott
Unit. The Fisher family contributed a 1.12-acre
Policy Purpose
Refuge System Mission and Goals and Refuge Pur-poses
(601 FW 1)
Reiterates and clarifies the Refuge System mission
and how it relates to the Service mission; explains
the relationship between the Refuge System mission,
goals, and purpose(s). It also includes the decision
making process for determining refuge purposes.
Biological Integrity, Diversity and Environmental
Health Policy (601 FW 3)
Provides guidance for maintaining and restoring,
where appropriate, the biological integrity, diversity,
and environmental health of the Refuge System.
Comprehensive Conservation Planning (602 FW 3) Describes the requirements and processes for develop-ing
refuge comprehensive conservation plans.
Appropriate Use (603 FW 1) Describes the initial decision process the refuge man-ager
follows when first considering whether or not to
allow a proposed use on a refuge. The refuge manager
must find a use appropriate before undertaking a com-patibility
review of the use.
Compatibility (603 FW 2) Details the formal process for determining if a use
proposed on a National Wildlife Refuge is compatible
with the Refuge System mission and the purposes for
which the refuge was established. Units of the Refuge
System are legally closed to all public access and use,
including economic uses, unless and until they are
officially opened through a compatibility determina-tion.
Appendix G contains several draft compatibility
determinations for proposed uses on Ellicott Slough
NWR. These will be open to public comment with the
Draft Plan and formalized with the Final Comprehen-sive
Conservation Plan.
Wildlife-Dependent Recreation (605 FW 1-7) Provides specific information and guidance for each of
the six priority wildlife-dependent uses: the policy for
the use; guiding principles for the use; guidelines for
program management; and guidelines for opening the
specific program.
Table 1. Key policies related to management of National Wildlife Refuges
Ellicott Slough NWR - Final Comprehensive Conservation Plan 5
Figure 1. San Francisco Bay NWR Complex Map
Monterey
Bay
Antioch Dunes NWR
Redwood City
San Pablo Bay NWR
Marin Islands NWR
Ellicott
Slough NWR
Salinas
River NWR
Don Edwards San
San Francisco Francisco Bay NWR
Bay
S..F..
Fremont
Oakland
Concord
Vallejo
Monterey
San Jose
Santa Cruz
San Rafael
San Francisco
MARIIN
ALAMEDA
SOLANO
SANTA CLARA
CONTRA COSTA
SAN
MATEO
MONTEREY
SANTA CRUZ
SONOMA
NAPA
Farallon NWR
San Francisco Bay National Wildlife Refuge Complex
C A L I F O R N I A
NEVADA
Enlarged Area
P a c i f i c O c e a n
±
0 5 10 20
km
0 5 10 20
0 250 Miles
Miles
Chapter 1
6 Ellicott Slough NWR - Final Comprehensive Conservation Plan
Figure 2. Ellicott Slough NWR Location Map
Larkin Valley Rd.
San Andreas Rd.
Willow Crk. Dr.
Fiesta Way
Mar Monte Rd.
Rampart Dr.
Harkins Slough Rd.
Cabrillo Hwy
BuenaVista Dr.
Metvier's Way
Ardilla Cyn Rd.
UV1
0 0.25 0.5 1
Miles
±
0 0.25 0.5 1
Kilometers
!
!
Monterey
Bay
Ellicott Slough
Area Monterey
Santa Cruz
Calabasas
Unit
Buena Vista
Property
Ellicott
Unit
Harkins Slough
Unit
Regional location
California Dept. of Fish and Game
U.S. Fish and Wildlife Service
Land ownership:
Ellicott Slough National Wildlife Refuge
Refuge Location
C A L I F O R N I A
Agreement
Approved Acquisition Boundary
Land status:
Easement
Ellicott Slough NWR - Final Comprehensive Conservation Plan 7
conservation easement in 1975, and the Lima family
contributed a 4.50-acre conservation easement in
1994. Both easements are within the approved
Refuge boundary. In total, the 133.24 acres owned
in fee title by the Service and the 35.11 acres
managed under easement or agreement comprise
the 168.35-acre Ellicott Unit today.
In June 1999, the Calabasas Unit was added to
the Refuge. A single-family home was slated for
development on this nearly 32-acre parcel but
was halted due to seismic, septic, and endangered
species restrictions (Santa Cruz long-toed
salamander and California red-legged frog were
found on the property). In 1999, The Trust for
Public Land (TPL) obtained an option to purchase
the site, with the intention to sell it to the Wildlife
Conservation Board (WCB) (USFWS 1999c). The
WCB was then awarded a Cal Trans Environmental
Enhancement and Mitigation grant to purchase
Calabasas for $250,000. The WCB transferred the
unit, at no cost, to the Service to maintain its coastal
scrub and pond habitat.
The Harkins Slough Unit was formerly an
agricultural property farmed for over 40 years by the
Bencich family. It was reclaimed by the Farm Service
Agency in 1994 when flooding from the Harkins
Slough waterway permanently inundated the
agricultural fields. The 116-acre property was then
transferred to the Service in 2005 due to its value as
freshwater wetland habitat for migratory birds.
The Ellicott Unit (168.35 acres), the Calabasas Unit
(31.20 acres), and the Harkins Slough Unit (116
acres) together comprise the Ellicott Slough NWR,
totaling 315.55 acres.
The 289-acre Buena Vista property was acquired
by TPL in 2004. Originally, a golf course had been
planned for the property until the Santa Cruz long-toed
salamander and California tiger salamander
were found to breed in the manmade ephemeral
pond on site. TPL led efforts to acquire the land, with
support from state agencies. This property was later
transferred to the CDFG. The Service is working
with CDFG to develop an agreement to cooperatively
manage the property that is within the approved
acquisition boundary for the Refuge. See Figure 2.
1.5.4 Refuge Purposes
Lands within the Refuge System are acquired and
managed under a variety of legislative acts and
administrative orders and authorities. The official
purpose or purposes for a refuge are specified in
or derived from the law, proclamation, executive
order, agreement, public land order, funding source,
donation document, or administrative memorandum
establishing, authorizing, or expanding a refuge,
refuge unit, or refuge subunit. The purpose of a
refuge is defined when it is established or when
new land is added to an existing refuge. When an
addition to a refuge is acquired under an authority
different from the authority used to establish the
original refuge, the addition takes on the purposes
of the original refuge, but the original refuge does
not take on the purposes of the addition. Refuge
managers must consider all of the purposes.
However, purposes that deal with the conservation,
management, and restoration of fish, wildlife, and
plants and their habitats take precedent over other
purposes in the management and administration of a
refuge (601 FW 1.5).
The Refuge System Improvement Act directs
the Service to manage each refuge to fulfill the
mission of the Refuge System, as well as the specific
purposes for which that refuge was established.
Refuge purposes are the driving force in developing
refuge vision statements, goals, objectives and
strategies in the CCP. Refuge purposes are also
critical to determining the compatibility of all
existing and proposed refuge uses.
Ellicott Slough National Wildlife Refuge was
established under the authority of two acts. These
acts and the corresponding purposes are:
Endangered Species Act of 1973 (16 U.S.C.
1531 et seq.) - “…to conserve (A) fish or
wildlife which are listed as endangered species
or threatened species .... or (B) plants ...”
Emergency Wetlands Resources Act of 1986
(16 U.S.C. 3901-3932) - “... the conservation
of the wetlands of the Nation in order to
maintain the public benefits they provide
and to help fulfill international obligations
contained in various migratory bird treaties
and conventions ...”
Chapter 1
8 Ellicott Slough NWR - Final Comprehensive Conservation Plan
1.5.5 Ecosystem Context and Related Projects
To the extent possible, a CCP will assist in
meeting conservation goals established in existing
national and regional plans, state fish and wildlife
conservation plans, and other landscape-scale plans
covering the same watershed or ecosystem in which
the refuge resides (602 FW 3.3). The Refuge falls
within the Central California Ecoregion. This
ecoregion consists of mountains, hills, valleys, and
plains in the southern Coast Ranges of California.
It is close enough to the Pacific Ocean for the
climate to be modified greatly by marine influence.
The purpose of establishing these ecoregions is to
develop and implement goals, priorities, objectives,
and actions that will ensure an “ecosystem
approach” to fish and wildlife conservation.
1.5.6 Conservation Priorities and Initiatives
The conservation priorities for Federally-listed
endangered and threatened species that are present
at a refuge are frequently reinforced by recovery
plans, conservation plans, and designation of critical
habitat. The primary conservation priority for the
Ellicott Slough NWR is recovering and conserving
the Santa Cruz long-toed salamander and other
sensitive amphibians. A revised recovery plan has
been developed to guide recovery efforts (USFWS
1999b). The recovery plan has been used to develop
some of the objectives and strategies in this CCP.
The Refuge also provides breeding habitat for
California red-legged frog and California tiger
salamader (CTS), both of which are Federally-listed
threatened species. A recovery plan was completed
for California red-legged frog in 2002, and critical
habitat was re-designated for the species in 2010.
Critical habitat for California red-legged frog can
be found on the Ellicott and Harkins Slough Units,
as well as the Buena Vista Property. The CTS is
Federally listed as threatened in Central California
and endangered in other parts of California (Santa
Barbara and Sonoma Counties). Critical habitat was
designated for all CTS populations in 2005, however
it does not include Santa Cruz County.
In addition to threatened and endangered
amphibians, the Refuge supports the endangered
robust spineflower. A recovery plan for robust
spineflower was completed in 2004 (USFWS 2004a)
and critical habitat was designated in 2002. Critical
habitat for spineflower can be found at the Buena
Vista property. While it is not known whether the
Federally-listed as threatened Santa Cruz tarplant
is present at the Refuge, there is designated critical
habitat at the Harkins Slough Unit.
1.5.7 Adaptive Management
The Service acknowledges that much remains to
be learned about the species, habitats, and physical
processes that occur on the Refuge and about the
ecological interactions between them. It follows
that uncertainty is an unavoidable component of
managing natural systems because of the inherent
variability in these systems and gaps in the
knowledge of their functions. Adaptive management
strives to reduce some of that uncertainty and
improve management over time. It is an iterative
process of evaluating and refining management
based on the results of management activities and
the status of the managed resource. The Service
has been practicing adaptive management on
the Refuge since 1991 and plans to continue the
practice. Accordingly, the management scenario
proposed in this CCP provides for ongoing
adaptive management of the Refuge; its adaptive
management component is described more fully in
Chapter 6, Plan Implementation.
Ellicott Slough NWR - Final Comprehensive Conservation Plan 9
Chapter 2. The Comprehensive Conservation
Planning Process
This CCP/EA for the Refuge is intended to meet
the dual requirements of compliance with the 1997
Improvement Act and NEPA of 1969 (42 USC 4321).
The development of this CCP/EA was also guided
by the Refuge Planning Policy outlined in Part 602,
Chapters 1, 3, and 4 of the Service Manual (USFWS
2000). Service policy, the 1997 Improvement
Act, and NEPA provide specific guidance for the
planning process. For example, Service policy and
NEPA require the Service to actively seek public
involvement in the preparation of environmental
documents such as EAs.
The purpose of the EA is to evaluate and disclose
the environmental effects of the management actions
detailed in the proposed action and alternatives
on the quality of the human environment. NEPA
requires the Service to give serious consideration
to all reasonable alternatives, including the “no
action” alternative, which represents continuation
of current conditions and management practices.
Alternative management scenarios were developed
as part of the planning process and can be found in
Appendix C (Environment Assessment).
2.1 The Planning Process: How the
CCP was Developed
Key steps in the CCP planning process are as follows
and are depicted in the CCP Process diagram.
1. Preplanning.
2. Identifying issues and developing a vision
statement.
3. Gathering information.
4. Analyzing resource relationships.
5. Developing alternatives and assessing
environmental effects.
6. Identifying a preferred alternative.
7. Publishing the draft CCP and NEPA document.
8. Documenting public comments on the Draft Plan.
9. Preparing the final CCP.
10. Securing approval of the Regional Director.
11. Implementing the plan.
The CCP may be amended as necessary at any time
in keeping with the adaptive management strategy.
Major revisions would require public involvement
and NEPA review.
2.1.1 Preplanning
The planning process for this CCP began in January
2008 with the collection of pertinent data and
selection of team members. A core team and an
extended team were formed to integrate stakeholder
input into the planning process (see Appendix I).
Refuge staff identified four primary areas of focus:
wildlife management, habitat management, wildlife-dependent
recreation, and environmental education.
These areas helped focus comments received from
the public during the scoping period into potential
objectives and strategies for the CCP.
2.1.2 Planning Hierarchy
The Service’s planning hierarchy, which determines
the direction of the goals, objectives, and strategies,
is a natural progression from the general to the
specific. Described as a linear process, the planning
hierarchy is rather a multi-dimensional flow that
is linked by the refuge purposes, missions, laws,
mandates, and other statutory requirements.
■■ The refuge purposes provide direction for
the refuge.
■■ A refuge vision broadly reflects the refuge
purpose(s), the Refuge System mission and
goals, other statutory requirements, and larger-scale
plans as appropriate.
■■ Goals define general targets in support of
the vision.
Chapter 2
10 Ellicott Slough NWR - Final Comprehensive Conservation Plan
■■ Objectives direct effort into incremental and
measurable steps toward achieving goals.
■■ Strategies identify specific tools to
accomplish objectives.
In practice, the process of developing vision, goals,
and objectives is iterative and dynamic. During the
planning process or as new information becomes
available, the plan continues to develop.
2.1.3 The Core Planning Team
The planning team responsible for leading the
CCP effort included Service planners, the Refuge
manager, the Refuge biologist, and visitor services
staff from the San Francisco Bay NWR Complex.
The members were responsible for researching
and generating the contents of the CCP document
and participated in the entire planning process.
Representatives from the California Department
of Fish and Game (CDFG) were also invited to
participate. Appendix I lists the members of the
core team and other participants.
2.1.4 The Extended Planning Team
The extended team is the advisory forum of the
CCP process. Its role is significant because of the
Refuge’s history of networking and partnerships
with local, state and Federal agencies, community
groups, research institutes, and non-profit
organizations concerned with the Refuge. Service
staff identified several participants including state
and Federal agency officials, local government
officials, non-profit organizations, community
groups, and other interested parties. The goal of
the extended team is to provide technical comments
on the goals, objectives, and strategies of the CCP
to improve the Service’s decision-making process.
Appendix I lists the members in the extended team.
Figure 3. The CCP Process Diagram
Ellicott Slough NWR - Final Comprehensive Conservation Plan 11
2.2 Public Involvement in Planning
Public involvement is an important and required
component of the CCP and NEPA processes.
Public outreach allows the Service to provide
updated information about the Refuge System and
the Refuge. More importantly, public involvment
allows Refuge staff to hear public comments,
concerns, and opportunities. Public input can
identify important issues regarding the Refuge and
its surrounding area.
A Notice of Intent to prepare a Comprehensive
Conservation Plan (CCP) and Environmental
Assessment was published in the Federal Register on
July 14, 2008. A planning update, which introduced
the Refuge and the planning process, was mailed to
over 100 agency and organization representatives,
members of the public, media, and elected
representatives in Santa Cruz County. The Refuge
held a public scoping period from July 14 through
August 13, 2008. During this period, upon request,
the Refuge staff met or spoke directly with neighbors
and partner organizations, including Watsonville
Wetlands Watch on October 2, 2008. The substance of
the comments or issues identified through the scoping
process is summarized in the Issues, Concerns, and
Opportunities section that follows.
2.2.1 Issues, Concerns, and Opportunities
Identified through Scoping
■■ Public trespass (e.g., bicycling, hiking,
horseback riding, dog walking) occurs on the
Refuge units.
■■ Illegal fishing occurs on the Harkins Slough Unit.
■■ Vehicular traffic is a major cause of amphibian
mortality, and roads exist between breeding
ponds and over-summering habitat.
■■ Invasive plants (e.g., eucalyptus: Eucalyptus
spp.), pampas or jubata grasses (Cortaderia
spp.), poison hemlock (Conium maculatum),
New Zealand spinach (Tetragonia
tetragonioides), and mustard (Brassica sp.)
continue to threaten native habitats.
■■ Intense farming in the area may employ practices
(such as pesticide and fertilizer use) that have
potentially adverse effects on amphibians.
■■ Drought years severely impact Santa Cruz long-toed
salamander (SCLTS) productivity and make
it difficult to assess the status of SCLTS and
California tiger salamander (CTS) populations.
■■ Occasional chytrid fungus (Batrachochytrium
dendrobatidis) outbreaks cause chytridiomycosis,
which threaten amphibian health.
■■ Mosquito control has been allowed in the past
for nuisance and health reasons; however, the
potential effects of control to amphibians are
still being evaluated.
■■ Invasive predators of amphibians (e.g.,
bullfrog, crayfish) tend to multiply quickly
and have the potential to decimate native
amphibian populations.
■■ The effects of climate change (e.g., temperature
fluctuations and narrowing wildlife habitat
ranges) on Refuge resouces. (For more
information on climate change, see Chapter 3.)
2.2.2 Additional Management Issues Identified
by Staff through Scoping
■■ Illegal off-road vehicle use, such as all-terrain
vehicle (ATV) and motorcycle, in the upland and
pond habitats on the Calabasas Unit.
■■ Few remaining upland habitats and ponds for
the SCLTS, CTS, and other native amphibians
due to habitat loss from development.
■■ Known SCLTS and CTS sites are non-contiguous,
preventing population exchange.
■■ Existing Refuge data on SCLTS and CTS is
sparse, limiting understanding of population
trends and habitat use.
■■ Amphibian malformation outbreaks caused by
trematode parasites.
2.3 Development of Refuge Vision
A vision statement is developed or reviewed for
each individual refuge unit as part of the CCP
process. Vision statements are grounded in the
unifying mission of the Refuge System and describe
the desired future conditions of the refuge in the
long term (more than 15 years). A vision statement
is based on the refuge’s specific purposes, the
resources present on the refuge, and any other
Chapter 2
12 Ellicott Slough NWR - Final Comprehensive Conservation Plan
relevant mandates. Chapter 5 presents the vision
statement for the Refuge.
2.4 Development of Refuge Goals,
Objectives and Strategies
The purpose for creating the Refuge was established
by law, Executive Order, and other mechanisms
described in Chapter 1. The 1997 Improvement
Act directs that the planning effort develop and
revise the management focus of the Refuge
within the Service’s planning framework-that is,
the Service mission, the Refuge System mission,
ecosystem guidelines, and refuge purposes. This is
accomplished during the CCP process through the
development of goals, objectives, and strategies.
Chapter 5 includes the goals, objectives and
strategies developed for the Refuge.
2.4.1 Goals
Refuge goals are necessary for outlining the desired
future conditions of a refuge in clear and succinct
statements. The Refuge System defines goals
as a “…descriptive, open-ended, and often broad
statement of desired future conditions that conveys
a purpose but does not define measurable units” (602
FW 1). Each goal is subdivided into one or more
objectives that define these desired conditions in
specific, measurable, and time-bounded terms. A
well-written goal directs work toward achieving a
refuge’s vision and, ultimately, the purpose(s) of a
refuge. Collectively, a set of goals is a framework
within which to make decisions.
2.4.2 Objectives, Rationale, and Strategies
After the refuge goals have been reviewed and
revised, various objectives, a rationale, and strategies
are developed to accomplish each of the goals.
Objectives: An objective is defined as a “concise
statement of what we want to achieve, how much we
want to achieve, when and where we want to achieve
it, and who is responsible for the work” (602 FW 1).
Objectives are incremental steps taken to achieve
a goal. They are derived from goals and provide a
foundation for determining strategies, monitoring
refuge accomplishments, and evaluating success.
The number of objectives per goal can vary but
should be developed to comprise those necessary
to satisfy the goal. In cases where there are many
objectives, an implementation schedule may be
developed. All objectives must possess the following
five properties: specific, measurable, achievable,
results-oriented, and time-fixed.
Rationale: Each objective should be supported
by a rationale. The degree of documentation can
vary, but at a minimum, the rationale should include
logic, assumptions, and sources of information.
Articulating a rationale promotes informed debate
on the objective’s merits, provides continuity in
management through staff turnover, and allows
reevaluation of the objective as new information
becomes available.
Strategy: A strategy is a “specific action, tool,
technique, or combination of actions, tools, and
techniques used to meet unit objectives” (602 FW
1). Well-written goals, objectives, and strategies
direct work toward achieving the refuge’s vision and
purpose. Multiple strategies can be necessary to
support an objective.
2.5 Development of Alternatives
The CCP process includes the development of
a range of reasonable alternatives that can be
implemented to meet the goals of the Refuge
System and the purpose of the Refuge. The Refuge
System defines alternatives as “…different sets
of objectives and strategies or means of achieving
refuge purposes and goals, helping fulfill the Refuge
System mission, and resolving issues…” (602 FW
1). NEPA also requires analysis of a no-action
alternative, which constitutes a continuation of
current conditions and management practices.
Development of action alternatives is based on
consideration of input from the scoping period, as
well as on input from the planning team and other
Service staff. The EA (Appendix C) describes the
development of alternatives and assessment of their
environmental effects, and it identifies the preferred
management alternative (proposed action). Once a
preferred alternative is selected, it is developed as
the objectives and strategies of the CCP.
Three alternatives were identified for analysis; these
are discussed in detail in the EA (Appendix C).
Ellicott Slough NWR - Final Comprehensive Conservation Plan 13
2.6 Selection of the Refuge
Proposed Action
The alternatives were analyzed in the EA (Ap-pendix
C) to determine their effects on the Refuge
environment. Based on this analysis, Alternative B
was selected as the proposed action because it best
achieves the Refuge goals and purposes in accor-dance
with Refuge System and Service missions.
Alternative B is founded upon the need for restoring
habitat, protecting wildlife, and focusing research
and monitoring programs on priority needs. The
alternative also integrates environmental educa-tion,
outreach, and wildlife-dependent recreation
objectives that will connect the public to the Refuge.
The management plan set forth in Alternative B is
described in Chapter 5, Management Direction, and
Chapter 6, Plan Implementation.
2.7 Plan Implementation
The CCP will be reviewed by Refuge staff to
coordinate annual work plans and update the
Refuge Operational Needs System database. This
database describes the unfunded budget needs
for each refuge and is the basis upon which the
Refuge receives funding increases for operational
needs. The CCP may also be reviewed during
routine inspections or programmatic evaluations.
Results of the reviews may indicate a need to
modify an integral part of plan implementation,
and management activities may be modified if the
desired results are not achieved. If minor changes
are required, the level of public involvement and
NEPA documentation will be determined by the
Refuge manager. The CCP will be formally revised
about every 15 years.
Santa Cruz long-toed salamander juveniles. Photo: USFWS
Ellicott Slough NWR - Final Comprehensive Conservation Plan 15
Chapter 3. Refuge and Resource Description
3.1 Geographic/Ecosystem Setting
The Refuge is located in Santa Cruz County, one-half
mile inland from Monterey Bay and four miles
west of Watsonville. The Refuge falls within the
Central California Ecoregion. This ecoregion
consists of mountains, hills, valleys, and plains in
the southern Coast Ranges of California. It is close
enough to the Pacific Ocean for the climate to be
modified greatly by marine influence. Elevation
ranges from sea level to 3,800 feet. The Refuge is
located in the Watsonville Slough system where
surface waters converge and eventually terminate
into Monterey Bay.
3.2 Description by Refuge Unit
3.2.1 Ellicott Unit
The main Ellicott Unit is located on Peaceful
Valley Drive off of San Andreas Road. A privately
operated Kampgrounds of America (KOA)
campground lies on the western border, and
approximately seven houses, agricultural fields, and
several small businesses are located in the valley
along the eastern border. Scattered houses are
located on the northern and southern boundaries.
Several California State Parks, open to the public,
(Manresa and Sunset State Beaches) are also
within two miles of the Ellicott Unit. The nearby
agricultural areas are dominated by cash crops
such as artichokes, strawberries, broccoli, lettuce,
cauliflower, and cut flowers.
The dominant habitats found on the Ellicott Unit are
northern coastal shrub, San Andreas coastal live oak
woodland, riparian woodland, closed-cone coniferous
forest, and coastal grassland. In addition to the Santa
Cruz long-toed salamander (SCLTS), California
tiger salamander (CTS) and small populations of
the robust spineflower have also been identified as
Federally-listed species present on the unit.
Past uses on the unit include livestock grazing,
farming of berry crops, and off-road vehicle use. A
residential house was also located on the property
and was demolished prior to Refuge acquisition.
The ephemeral Ellicott Pond on the Ellicott Unit
is used by salamanders during breeding. It is
unknown whether the Ellicott Pond is naturally
occurring or man-made. In 1997, the Refuge
attempted to create an additional breeding
pond on the unit (Prospect Pond). A pond area
was excavated, and a partial earthen berm was
constructed to surround the site. Water levels
were to be controlled by a culvert
installed through the earthen
berm. A well was also established
on the hilltop above the pond to
augment water levels as needed.
Plastic piping was laid from the
well to the pond site. A temporary
pump and generator were needed
to transport the water. Subsequent
years resulted in poor water
retention. The pond dried too early
in the season to ensure larvae and
tadpole metamorphosis, and water
augmentation from the well would
have been needed throughout the
entire spring and summer. Initial
monitoring surveys showed limited
Ellicott Unit. Photo: USFWS Pacific tree frog (Pseudacris
Chapter 3
16 Ellicott Slough NWR - Final Comprehensive Conservation Plan
regilla) use. In 2004, a hydrologic survey of the
area was conducted, and a new pond design was
developed. The Service sees a need for further
study of the hydrologic conditions and possible
causes of the poor water retention.
3.2.2 Calabasas Unit
The Calabasas Unit is located within the upper
portion of Larkin Valley area, parallel to Larkin
Valley Road where it intersects Mar Monte Avenue.
It is bordered to the west by Milky Way and to
the east by a dirt fire road. Ardilla Canyon Road
is to the south of the unit. The Calabasas Unit is
surrounded by residential properties and houses.
Several horse stables and horse pastures are also
located nearby.
The dominant habitats found on the Calabasas Unit
are northern coastal shrub, riparian woodland,
coastal grassland, San Andreas coastal live oak
woodland, and ephemeral pond.
Historically, Calabasas Pond was a reservoir with
an earthen dam across the southern end, and the
upland habitat was grazed by livestock. Santa
Cruz County Public Works intentionally breached
a section of the dam about 1980, after it was
determined to be structurally unsound. This breach
created the existing hydrologic site conditions, with
two to four feet of rainwater accumulating annually
in the shallow footprint of the former reservoir.
When the pond exceeds capacity, the excess water
overtops the lowest southwest section of bank
and drains along the hillside. The pond typically
remains wet from late fall through mid summer.
Although this pond was not originally created for
salamanders and frogs, it has become a secure
breeding site for SCLTS with associated over-summering
upland habitats.
In 1994, it was observed by the CDFG that
rainwater spillover was gradually eroding the
adjacent hillside, as well as potentially threatening
the integrity of the earthen pond bank. A
temporary fix of rip rap boulders was placed in the
wash-out area to prevent further damage. During
the El Nino winter of 1997–1998, substantially
above-average rainfall caused a breach in the
spillway section of earthen bank. The increase in
water flow and velocity through the wash-out caused
further scouring of the area.
In 2006, the Service permanently repaired the
breach in the Calabasas Pond bank. This action was
prescribed in the Revised Recovery Plan for the
Santa Cruz long-toed salamander (USFWS 1999b).
As part of the breach repair, the bank was replaced
with a levee and fortified. A water control structure
was installed in the new bank to manipulate water
levels and to prevent erosion and bank failure from
re-occurring during substantially above-average
rainfall years.
3.2.3 Harkins Slough Unit
The dominant habitats found on the Harkins Slough
Unit are former farmlands with approximately 51
acres of freshwater wetland, coastal grassland,
San Andreas coastal live oak woodland, northern
coastal shrub, and native and non-native herbaceous
vegetation. The unit is bordered to the west and
south by Harkins Slough Road, off of Buena Vista
Drive. It is adjacent to the Buena Vista landfill,
a plant nursery, a residential neighborhood, and
a correctional facility along the western border.
Agricultural fields and a former dairy are adjacent
to the eastern border.
The Harkins Slough waterway itself continues
upstream as a channel north of the unit and remains
a large, open permanent freshwater wetland
downstream to the south, beyond the flooded
Harkins Slough Road. It is a natural drainage valley
that flows to Watsonville Slough, which in turn flows
into the Pajaro River before draining into the ocean.
The Refuge staff has observed large numbers of
gulls using this unit for roosting, probably due to the
proximity to a landfill. A variety of waterfowl species
use the slough, including mallard, northern shoveler,
cinnamon teal, and pintail. Flocks of white pelicans
have also been observed feeding and roosting.
The unit contains several buildings, roads, wells,
and utility infrastructure that are in disrepair.
The buildings consist of three houses, a barn,
warehouses, and storage and equipment sheds.
There are three agricultural and two drinking water
wells on the site.
Several parcels within the vicinity of this unit are
owned by the California Department of Fish and
Game or are in easements and protected from
development. In 2009–2010, the Land Trust of
Ellicott Slough NWR - Final Comprehensive Conservation Plan 17
Santa Cruz County acquired approximately 486
acres southeast of the Harkins Slough Unit and
is developing a management plan that includes
slough restoration.
3.2.4 Buena Vista
The Buena Vista property is two miles west of
the Watsonville Airport and 1.5 miles west of
Watsonville. It is bound on the northeast by
Highway 1, on the south by Fiesta Way and Rancho
Road, and on the west by cultivated lands east of
Willow Spring Road. It is a largely undisturbed
micro-ecosystem consisting of a mosaic of San
Andreas coastal live oak woodland, northern coastal
shrub, San Andreas maritime chaparral, and
Monterey pine woodland.
Buena Vista Pond is a small manmade ephemeral
pond on the southeast portion of the site. Santa
Cruz long-toed salamander and CTS have been
found to breed at the site.
Several plants identified on the property are listed
by the state as species of concern, including robust
spineflower, Hooker’s manzanita (Arctostaphylos
hookeri ssp. hookeri), California bottlebrush
(Elymus californicus), and Kellogg’s horkelia
(Horkelia cuneata ssp. sericea). Robust spineflower
has been found on the Buena Vista property,
however population estimates are not current.
A house and garage are located on Buena Vista;
they were built in 1951, according to Santa
Cruz County Assessor’s records. A well is also
associated with the property and is used to supply
the residence with water.
3.3 Physical Resources
3.3.1 Climate and Air Quality
Santa Cruz County has warm summers and mild
winters. Mean annual temperature in the county
ranges from 54 to 58 degrees Fahrenheit. Near
the coast, the difference between the mean daily
minimum and maximum temperatures ranges from
about 20 to 30 degrees (NRCS 2007a). In the coastal
area where the Refuge is located, the mean daily
temperature is about 50 to 55 degrees Fahrenheit
minimum and 70 to 75 degrees Fahrenheit
maximum. The mean daily temperature in January
is about 35 to 40 degrees Fahrenheit minimum
and 57 to 62 degrees Fahrenheit maximum. Mean
Harkins Slough Unit. Photo: USFWS
Chapter 3
18 Ellicott Slough NWR - Final Comprehensive Conservation Plan
annual precipitation of about 30 inches is typical of
the Santa Cruz area, and 20–25 inches is typical of
the Watsonville area (NRCS 2007a).
Air quality is regulated by the Federal Clean Air Act
(42 U.S.C. §§ 7401, as amended), which mandates
the establishment of ambient air quality standards
and requires areas that violate these standards
to prepare and implement plans to achieve the
standards by certain deadlines. Areas that do not
meet Federal primary air quality standards are
designated as “nonattainment” areas. Areas that
comply with Federal air quality standards are
designated as “attainment” areas. Attainment and
nonattainment designations are pollutant specific.
Agencies involved with air pollution management
include the U.S. Environmental Protection Agency,
California Air Resources Board, and the Monterey
Bay Unified Air Pollution Control District. State and
Federal governments have developed the following
attainment standards for several criteria pollutants.
■■ Particulate matter less than 10 microns in
diameter (PM10)
■■ Ozone
■■ Carbon monoxide (CO)
■■ Nitrogen dioxide (NO2)
■■ Sulfur dioxide (SO2)
■■ Sulfates
■■ Lead
The Refuge is located in the North Central Coast
Air Basin. The pollutant measures for 2006 are as
follows (CARB 2007).
Table 2. Pollutant measures for North Central
Coast Air Basin - 2006
State
Standards
Federal
Standards
Ozone Nonattainment Unclassified/attainment
PM10 Nonattainment Unknown
CO Attainment Attainment
NO2 Attainment Unclassified/
Attainment
SO2 Attainment Unclassified
Sulfates Attainment n/a
Lead Attainment n/a
Source: CARB 2007
3.3.2 Climate Change and Greenhouse
Gas Emissions
Global climate change is a problem caused by
combined worldwide greenhouse gas (GHG)
emissions, and mitigating global climate change will
require worldwide solutions. GHGs play a critical
role in the Earth’s radiation budget by trapping
infrared radiation emitted from the Earth’s surface,
which could have otherwise escaped to space.
Prominent GHGs contributing to this process
include water vapor, carbon dioxide (C02), nitrous
oxide (N20), methane (CR.), ozone, and certain
hydro- and fluorocarbons. This phenomenon, known
as the “greenhouse effect” keeps the Earth’s
atmosphere near the surface warmer than it would
be otherwise and allows for successful habitation
by humans and other forms of life. Increases in
these gases lead to more absorption of radiation
and warm the lower atmosphere further, thereby
increasing evaporation rates and temperatures
near the surface. Emissions of GHGs in excess of
natural ambient concentrations are thought to be
responsible for the enhancement of the greenhouse
effect and to contribute to what is termed “global
warming,” a trend of unnatural warming of the
Earth’s natural climate. Climate change is a global
problem, and GHGs are global pollutants, unlike
criteria air pollutants (such as ozone precursors)
and toxic air contaminants, which are pollutants of
regional and local concern (USFWS, CDFG 2009a).
The Intergovernmental Panel on Climate Change
(IPCC) has been established by the World
Meteorological Organization and United Nations
Environment Programme to assess scientific,
technical and socio- economic information relevant
for the understanding of climate change, its
potential impacts and options for adaptation
and mitigation. The IPCC predicts substantial
increases in temperatures globally of between 1.1
to 6.4 degrees Celsius (depending on scenario)
(Intergovernmental Panel on Climate Change 2007).
Climate change could impact the natural
environment in California in the following ways,
among others:
■■ Rising sea levels along the California
coastline, particularly in San Francisco Bay
and the Sacramento-San Joaquin Delta due to
ocean expansion;
Ellicott Slough NWR - Final Comprehensive Conservation Plan 19
■■ Extreme-heat conditions, such as heat waves
and very high temperatures, which could last
longer and become more frequent;
■■ An increase in heat-related human deaths,
infectious diseases and a higher risk of
respiratory problems caused by deteriorating
air quality;
■■ Reduced snow pack and stream flow in the
Sierra Nevada mountains, affecting winter
recreation and water supplies;
■■ Potential increase in the severity of winter
storms, affecting peak stream flows and flooding;
■■ Changes in growing season conditions that could
affect California agriculture, causing variations
in crop quality and yield;
■■ Changes in distribution of plant and wildlife
species due to changes in temperature,
competition from colonizing species, changes
in hydrologic cycles, changes in sea levels, and
other climate-related effects.
For further discussion of climate change, refer to
Appendix C – Environmental Assessment.
These changes in California’s climate and
ecosystems are occurring at a time when California’s
population is expected to increase from 34 million
to 59 million by the year 2040 (California Energy
Commission 2005).
As such, the number of people potentially affected
by climate change as well as the amount of
anthropogenic GHG emissions expected under
a “business as usual” scenario are expected to
increase. Similar changes as those noted above for
California would also occur in other parts of the
world with regional variations in resources affected
and vulnerability to adverse effects.
GHG emissions in California are attributable
to human activities associated with industrial
manufacturing, utilities, transportation, residential,
and agricultural sectors (California Energy
Commission 2006) as well as natural processes.
United States Greenhouse Gas Emissions
In 2006, total U.S. GHG emissions were 7,054.2
million metric tons (MMT) CO2 Eq. Overall, total U.S.
emissions have risen by 14.7 percent from 1990 to 2006.
The primary GHG emitted by human activities
in the United States was CO2, representing
approximately 84.8 percent of total GHG emissions.
The largest source of CO2, and of overall GHG
emissions, was fossil fuel combustion. CH4,
emissions, which have declined from 1990 levels,
resulted primarily from enteric fermentation
associated with domestic livestock, decomposition
of wastes in landfills, and natural gas systems.
Agricultural soil management and mobile source
fossil fuel combustion were the major sources
of N2O emissions. The emissions of substitutes
for ozone depleting substances and emissions
of HFC-23 during the production of HCFC-22
were the primary contributors to aggregate HFC
emissions. Electrical transmission and distribution
systems accounted for most SF6 emissions, while
PFC emissions resulted from semiconductor
manufacturing and as a by-product of primary
aluminum production (U.S. Environmental
Protection Agency 2008).
California Greenhouse Gas Emissions
Worldwide, California is the 12th to 16th largest
emitter of CO2 (California Energy Commission
2006), and is responsible for approximately 2
percent of the world’s CO2 emissions (California
Energy Commission 2006).
Transportation is responsible for 41percent of the
state’s GHG emissions, followed by the industrial
sector (23 percent), electricity generation (20
percent), agriculture and forestry (8 percent)
and other sources (8 percent) (California Energy
Commission 2006). Emissions of carbon dioxide
and nitrous oxide are byproducts of fossil fuel
combustion, among other sources. Methane, a
highly potent GHG, results from off-gassing
associated with agricultural practices and landfills,
among other sources. Sinks1 of carbon dioxide
include uptake by vegetation and dissolution into
the ocean. California GHG emissions in 2002 totaled
approximately 491 MMT-CO2 eq.
1 A carbon dioxide sink is a resource that absorbs carbon dioxide
from the atmosphere. The classic example of a sink is a forest in
which vegetation absorbs carbon dioxide and produces oxygen
through photosynthesis.
Chapter 3
20 Ellicott Slough NWR - Final Comprehensive Conservation Plan
3.3.3 Climate Change Regulation
Federal Climate Change Regulations
Twelve U.S. states (including California) and
cities, in conjunction with several environmental
organizations, sued to force the EPA to regulate
GHGs as a pollutant pursuant to the Clean Air
Act (Massachusetts vs. Environmental Protection
Agency et al. [U.S. Supreme Court No. 05-1120].
Argued November 29, 2006. Decided April 2, 2007).
The court ruled that the plaintiffs had standing to
sue, that Clean Air Act does give EPA the authority
to regulate tailpipe emissions of GHG, and the
EPA is required to review its contention that it has
discretion in regulating carbon dioxide and other
GHG emissions. No regulations have been proposed
by the EPA to date pursuant to this ruling.
In February 2002, President Bush committed
the United States to a comprehensive strategy to
reduce the GHG emission intensity of the American
economy by 18 percent by 2012. In April 2008,
President Bush announced a new national goal to
stop the growth in U.S. GHG emissions by 2025.
Although there is substantial work underway by the
current administration of President Obama and new
policies on GHG emissions are expected, no specific
new policies on GHG emissions have been adopted
as of March 2010.
Thus, at present, there are no Federal regulations
specifically limiting the GHG emissions overall.
Department of the Interior Climate
Change Requirements
Each bureau and office of the Department must
consider and analyze potential climate change
impacts when undertaking long-range planning
exercises, setting priorities for scientific research
and investigations, developing multi-year
management plans, and making major decisions
regarding potential use of resources under the
Department’s purview. These requirements were
set forth in Secretary’s Orders No. 3226 and 3285,
and remain in effect. The organizational changes
made by this Order will enable the bureaus and
agencies to fulfill these planning requirements.
The Service’s Climate Change
Requirements
Increasing carbon dioxide and other greenhouse gas
emissions from anthropogenic sources have altered
the temperature over the last century more than any
other time in history. Such temperature changes can
have different consequences worldwide from sea-level
rise to greater meteorological fluctuations. The
Service recognizes that a changing climate will affect
natural resources and has been charged by Congress
(H. CON. RES. 2006) to address these effects in
CCPs. This challenge is especially important at the
Refuge in light of the sensitivity of amphibians to
temperature fluctuations and narrow habitat ranges.
For further discussion of climate change, refer to
Appendix C – Environmental Assessment.
Local Climate Change Regulations
The Monterey Bay Unified Air Pollution Control
District (MBUAPCD) presently has no guidance
concerning the California Environmental Quality
Act (CEQA) evaluation of GHG emissions and no
regulatory requirements.
3.3.4 Topography
The topography of the Refuge units ranges from
hilly to flat. The Refuge is closest to the city of
Watsonville, which has elevation ranging from 20
to 900 feet. At the Ellicott Unit, elevation varies
from 120 to 180 feet between the slough and the
top of the adjoining hills. There are no permanent
streams, and natural drainage systems are not well
developed. The groundwater table is less than 150
feet below the surface. The Buena Vista property is
surrounded by hilly, wooded terrain. The property
slopes in elevation from 250 to 450 feet mean sea
level. The land form includes three ridge lines and
four drainage valleys extending in a north-south
direction (Hanna and Associates 2001).
3.3.5 Geology, Soils, and Hydrology
The geology of the Refuge area is described as
beach and dune sand (Quaternary). There are
several soil types on the Refuge (see Figure 4).
Baywood loamy sand is characteristically deep
Ellicott Slough NWR - Final Comprehensive Conservation Plan 21
Figure 4. Soil Types on the Ellicott Slough NWR
Ardilla CynRd.
Metvier's Way
Mar MonteAve.
Cabrillo Hwy.
Larkin Valley Rd.
Buena Vista Dr.
San Andreas Rd.
White Rd.
Rampart Rd.
E. Bel Mar Dr.
Alta Dr.
Fiesta Way
Airport Blvd.
Tulsa Ln.
Spring Valley Rd.
Water Tank Rd.
Harkins Slough Rd.
Willow Creek Dr.
Rountree Ln.
Ridgeway St.
1
1
2
4
1
9
5
4
5
3
9
4
8
6
3
6
3
9
4
9
9
5
3
7
3
7
3
8
8
7
4
3
10
8
10
0 0.25 0.5 1
Miles ± 0 0.25 0.5 1
Kilometers
Calabasas
Unit
Buena Vista
Property
Ellicott
Unit
Harkins Slough
Unit
Ellicott Slough National Wildlife Refuge
Soils
1 - Baywood Loamy sand
2 - Clear Lake clay
3 - Elder sandy loam
4 - Elkhorn sandy loam
5 - Elkhorn-Pfeiffer complex
6 - Fluvaquentic Haploxerolls-
Aquic Xerofluvents
7 - Pfeiffer gravelly sandy loam
8 - Tierra-Watsonville complex
9 - Watsonville loam
10 - Water
Soil Name
UV1
Sources:
-USDA, Natural Resources Conservation Service
-National Agriculture Imagery Program, 2009
Chapter 3
22 Ellicott Slough NWR - Final Comprehensive Conservation Plan
and drains somewhat excessively (NRCS 2007b).
Sand dunes are made up of this soil type. Elder
sandy loam is considered a well-drained soil and
typically has a surface layer of dark grayish brown
and grayish brown, medium acid and slightly acidic
sandy loam about 23 inches thick. Elkhorn soils are
well drained and are located on marine terraces and
old alluvial fans. Typically, the surface layer is very
dark grayish brown, slightly acid and medium acid
sandy loam about 21 inches thick. The subsoil to a
depth of 61 inches is pale brown and variegated light
gray and very pale brown neutral sandy clay loam.
Fluvaquentic Haploxerolls-Aquic Xerofluvents
complex soils are considered moderately well
drained, while the Tierra-Watsonville complex is
considered moderately to poorly well-drained.
Pfeiffer gravelly sandy loam is a deep, well-drained
soil located on hills. It formed in material weathered
from granitic rock, sandstone, or marine sediment.
Watsonville loam consists of very deep, somewhat
poorly drained soils on old coastal terraces. These
soils formed in alluvium.
The geology of Buena Vista is relatively uniform and
is mapped as Pleistocene non-marine Quaternary
Aromas Formation. The soil at the Buena Vista
property is described as sandy loam; the ridge soil
tends to be shallow and finer textured. Soils in the
lower lying positions tend to have argillic horizons
(clay-enriched subsoils). Soils in the valleys vary
from sandy to hydric. Buena Vista is a high-value
groundwater recharge zone.
The Refuge is located within the Pajaro River
Watershed. The Pajaro River Watershed is sourced
by the Pajaro River and local runoff. Within the
watershed, the Watsonville Slough System carries
surface water through the different Refuge units.
It is a remnant of a more extensive wetland and
estuarine complex. The system has been modified
to meet adjacent land use needs such as agriculture
and urban development. The Watsonville Slough
System currently is made up of six major branch
sloughs as depicted in Figure 5. This 800-acre
system is made up of coastal salt marsh, seasonal
wetlands, brackish and freshwater emergent marsh,
and riparian communities. The Watsonville Slough
System also receives runoff from the 13,000-acre
Pajaro River Watershed, which includes a mix of
urban, industrial, rural residential, agricultural,
and open space land uses (California Coastal
Commission 2006). The Watsonville Slough
System continues down a broad alluvial flood plain
with irrigated agriculture as the primary land
use and finally drains near a small residential
dunes complex to the Pajaro Lagoon, joining the
Monterey Bay and Pacific Ocean (Hager et al.
2004). However, flows have been observed in the
reverse direction, from the mouth to the watershed.
Factors of this phenomenon include high ocean
waves, backwater flow from the neighboring Pajaro
River, active pumping of the watershed, and land
subsidence (Hager et al. 2004). The Refuge is
sensitive to extreme flood events in the sloughs,
with the Harkins Slough and Calabasas Units
located within the Federal Emergency Management
Agency floodplain.
3.3.6 Water Supply and Water Quality
Santa Cruz County is one of the few California
counties that are not dependent on water sources
from outside its boundaries. However, increased
water demand has exceeded currently developed
surface sources and depleted groundwater supplies.
Santa Cruz County primarily depends on surface
flow and wells for its water supply, with some surface
water inflow from San Benito County and some
groundwater inflow from Monterey County (SCRCD
2008). The Refuge ephemeral ponds are heavily
dependent on the rainfall captured in this slough
system and watershed, as well as upland runoff.
Harkins Slough, part of the Watsonville Slough
System (see Figure 5), is the largest and most
northerly slough in the system. Its drainage
initiates in Larkin Valley, flowing eastward under
Highway One, between Airport Boulevard and
Buena Vista Road. Near the county landfill,
Harkins Slough broadens, flooding Harkins Slough
Road year round. Below this point, the inaccessible
Gallighan Slough merges with Harkins Slough.
Continuing south, it merges into Watsonville Slough
at the Pajaro Valley Water Management Pump
Station off San Andreas Road, and then flows into
the Pajaro River and finally into the Monterey Bay
(Chirco-Mcdonald 2007).
Water quality on the Refuge is heavily influenced
by agricultural practices in the surrounding
region. Santa Cruz County is the second smallest
county in California and the smallest agricultural
county in California. Santa Cruz County ranked
Ellicott Slough NWR - Final Comprehensive Conservation Plan 23
Figure 5. Watsonville Slough System. Source: Watsonville Wetlands Watch
(http://watsonvillewetlandswatch.org/images/sloughmapLarge.jpg)
Chapter 3
24 Ellicott Slough NWR - Final Comprehensive Conservation Plan
20th out of 58 counties in value of agricultural
production in 2005, with farm gate sales totaling
$418 million (UCCE 2005). Watsonville Slough
and the Pajaro River (downstream of Watsonville
Slough) are both listed in the 2006 Federal Clean
Water Act Section 303(d) as waterbodies that
do not meet water quality objectives and do not
support beneficial uses. The listing established a
priority for developing a control plan to address
the impairment of these waterbodies. Primary
pollutants to the Watsonville Slough are pathogens
from urban runoff and/or storm sewers, unknown
sources, and nonpoint sources. Pesticides are
also another stressor on the slough as a result of
agriculture, irrigated crop production, agriculture
storm runoff, agriculture irrigation tail water,
and nonpoint sources (CCRWQCB 2006). Fecal
coliform is another concern. Sampling by the Santa
Cruz County Environmental Health Department
(1977–2000) determined that 10 of 11 sites surveyed
in the county exceeded the Central Coast Regional
Water Quality Control Board’s Basin Plan standards
(Hager et al. 2004). A 2004 sampling of Watsonville
Slough sites revealed that fecal coliform levels in the
area compared closely with regional levels (Hager et
al. 2004).
Other water quality information for the area is
limited. No U.S. Geological Survey (USGS) survey
sites were found in Santa Cruz County. The Coastal
Watershed Council conducted a Clean Streams
Citizen Monitoring Program of the Watsonville
Slough System (in 2004) and the Harkins Slough
Watershed (in 2007) using volunteer participation
to gather surface water quality field data. The
surveys found that the Watsonville Slough System
has consistently high nitrate and bacteria, as well
as low dissolved oxygen levels that often exceeded
the water quality objectives based on the Basin
Plan developed by the Central Coast Regional
Water Quality Control Board (CCRWQCB) (Coastal
Watershed Council 2004). The 2004 survey also
found that E. coli and total coliform levels exceeded
state water quality objectives at most of the survey
stations. Nitrate and ammonia levels also exceeded
acceptable CCRWQCB levels.
Although Harkins Slough is part of the Watsonville
Slough System described above, the Harkins
Slough surveys found low nutrient results, with
orthophosphates and nitrate having the lowest
number of exceedences based on unofficial Central
Coast Ambient Monitoring Program (CCAMP)
water quality objectives (Coastal Watershed Council
2007). Dissolved oxygen and pH levels were within
acceptable ranges of the unofficial CCAMP water
quality objective. However, the survey results found
high levels of ammonia, E. coli, and total coliform
in a majority of the samples. These high levels
were thought to be attributed to large number of
birds [gulls] frequenting the survey area and/or
surrounding livestock fields. Total coliform count
provides an indicator of pathogen conditions in the
water. Testing for indicator bacteria monitors the
potential presence of disease-causing organisms.
Indicator bacteria are types of bacteria not normally
found in high numbers in oceans, rivers, or creeks
but always found in sources of fecal contamination.
Though they are not typically disease-causing
organisms themselves, they can be indicative of the
presence of such organisms. Studies have shown
that when concentrations of indicator bacteria
exceed certain levels in waters used for water body
contact recreation, individuals exposed to these
waters may have a greater chance of getting sick
(www.ccamp.org ) (Coastal Watershed Council 2007).
Based upon results from the 2009 program and
previous years, continued monitoring is a key factor
in working towards watershed restoration. In
addition, increased pressure from urban development
and the region’s intense commercial agriculture
place significant strain upon the Watsonville Slough
System, creating further need for study to move
toward restoration of the watershed.
3.3.7 Hazardous Materials and Contaminants
A contaminant assessment process was conducted
in May 1999 on the Ellicott Unit (USFWS 1999a).
The report raised a number of concerns, including
pesticide exposure from adjacent agricultural lands,
application of methoprene to vernal breeding ponds,
and the potential for an accidental spill of hazardous
material or petroleum compounds from a train
derailment. Since 2000, the Refuge has not permitted
the use of methoprene by the Santa Cruz County
Mosquito and Vector Control District in ponds used
by SCLTS and CTS for breeding. As of 2010, the
Refuge has stopped the use of methoprene by the
Santa Cruz County Mosquito and Vector Control
District, in ditches that fill seasonally with water, until
Ellicott Slough NWR - Final Comprehensive Conservation Plan 25
a mosquito management plan and environmental
compliance are completed.
When the Calabasas Unit was acquired, the
acquisition assessment noted no known uses or
sources of hazardous materials on the property. In
several areas, corroded, non-functional water pipes
were identified. A Level I Environmental Site
Assessment was conducted in 1998. Nearby above-ground
storage tanks, electrical transmission lines,
and non-functional water pipes were initially noted
as potential hazardous materials (USFWS 1998).
Upon further investigation, the storage tanks and
water pipes were deemed innocuous.
Whether there are contaminants or hazardous
materials present on the Buena Vista property is
unknown; the property has not been surveyed.
During the acquisition assessment of the Harkins
Slough Unit, Level I and II Pre-Acquisition Surveys
identified several environmental concerns, including
neighboring and on-site factors. Neighboring
factors included impacts to groundwater and soil
from the adjacent Buena Vista Landfill and nearby
Western Farm Services, a former commercial
fertilizer operation. There were a variety of
discarded heavy equipment and several chemical
storage containers, some of which were leaking.
Concerns were noted that that the old containers
and farming equipment contained contaminants that
could runoff into the slough. The heavy equipment
and containers were removed before acquisition.
Soil, surface water, groundwater, and drinking water
well sampling was also conducted during the pre-acquisition
surveys in 2004 (USFWS 2005b). Soil
sampling analyzed for volatile organic compounds
(VOCs), chlorinated pesticides and herbicides, some
metals, and some nitrate sampling. Of 18 samples,
only one sample exceeded project screening levels
(USEPA Region IX Preliminary Remediation Goals-
PRG). This sample detected methylene chloride,
chlordane, chromium, and lead. Low concentrations
of pesticides and methylene chloride were present
on the unit. Low VOC levels were apparent but
considered typical at this location. Arsenic was also
found in a subsequent 2004 survey.
Ellicott Unit Calabasas
Unit
Harkins
Slough Unit
Buena Vista
Property
Habitat Type Acres* Acres* Acres* Acres*
Acacia stands 0 0 0.2 6.2
Coastal grassland 24.5 5.6 13.8 3.4
Bare/developed/roads 2.7 0.4 0.5 1.2
Northern coastal shrub 41.4 12.6 6.2 51.9
Eucalyptus stands 5.3 0.0 0.0 13.2
San Andreas maritime chaparral 0.0 0.0 0.0 33.1
Closed-cone coniferous forest 19.8 0.0 0.0 21.1
San Andreas coastal live oak woodland 38.2 3.8 8.9 158.8
Ephemeral pond 3.7 1.9 0.0 0.4
Riparian woodland 24.7 6.8 5.2 0.1
Native and non-native herbs 7.0 0.0 6.5 0.0
Water 0.0 0.0 50.8 0.0
Freshwater marsh 0.0 0.0 16.7 0.0
Total Acres 167.3 31.1 108.8 289.4
*Habitat acreages are based on GIS analyses and satellite imagery with limited field sampling, and therefore are
general estimates.
Table 3. Ellicott Slough NWR - Acreages of habitat types by unit
Chapter 3
26 Ellicott Slough NWR - Final Comprehensive Conservation Plan
Figure 6. Vegetation – Ellicott Unit
San Andreas Rd.
Ellicott Slough Rd.
Buena Vi sta Dr.
Spring Valley Rd.
±
Ellicott Slough National Wildlife Refuge
Vegetation - Ellicott Unit
0 250 500 1,000 1,500
feet
0 100 200 400
meters
Closed-cone coniferous forest
San Andreas coastal live oak woodland
Riparian woodland
Northern coastal shrub
Coastal grassland
Ephemeral pond
Eucalyptus stands
Semi-natural herbaceous stands
Bare/roads/developed
Ellicott Slough NWR - Final Comprehensive Conservation Plan 27
Figure 7. Vegetation – Calabasas Unit
Ardilla Canyon Rd.
Milky Way
Larkin Valley Rd.
White Rd.
±
Ellicott Slough National Wildlife Refuge
Vegetation - Calabasas Unit
San Andreas coastal live oak woodland
0 100 200 400 600
feet
0 50 100 200
meters
Riparian woodland
Northern coastal shrub
Coastal grassland
Ephemeral pond
Bare/roads/developed
Chapter 3
28 Ellicott Slough NWR - Final Comprehensive Conservation Plan
Figure 8. Vegetation – Harkins Slough Unit
Harkins Slough Rd.
Rountree Ln.
±
Ellicott Slough National Wildlife Refuge
Vegetation - Harkins Slough Unit
San Andreas coastal live
oak woodland
Semi-natural herbaceous
stands
Bare/roads/developed
Riparian woodland
Northern coastal shrub
Coastal grassland
Freshwater marsh
Water
Acacia stands
0 250 500 1,000 1,500
feet
0 100 200 400
meters
Ellicott Slough NWR - Final Comprehensive Conservation Plan 29
Figure 9. Vegetation – Buena Vista Property
Willow Crk. Dr.
Cabrillo Hwy
UV1
Cabrillo Hwy.
0 250 500 1,000 1,500
feet
±
Ellicott Slough National Wildlife Refuge
Vegetation - Buena Vista Property
Buena Vista
Property
Ellicott
Unit
0 100 200 400
meters
Ephemeral pond
Eucalyptus stands
Acacia stands
Bare/developed/roads
Closed-cone coniferous forest
San Andreas coastal live oak woodland
Riparian woodland
San Andreas maritime chaparral
Northern coastal shrub
Coastal grassland
Freshwater Marsh
Chapter 3
30 Ellicott Slough NWR - Final Comprehensive Conservation Plan
Surface water sampling revealed lead concentrations
that exceeded the maximum contaminant level
(treatment action level of 15μg/l and the National
Recommended Water Quality Criteria for Priority
Toxic Pollutants criterion). Groundwater sampling
showed that barium, chromium, lead, selenium, and
nitrate concentrations exceeded project screening
levels by a significant margin (USFWS 2005b).
Drinking water well sampling tested positive for
coliform bacteria and fecal coliform, indicating
contamination from human or animal waste.
Samples taken from buildings for lead and asbestos
confirmed that lead was found in painted surfaces
and asbestos in the building materials.
Prior to the transfer of the Harkins Slough Unit
to the Refuge, the Farm Service Agency (FSA)
required the former tenants to conduct a clean-up
of the property. All chemical storage containers and
the majority of the discarded farming equipment
were removed from the site.
In 2006, follow-up water quality monitoring
was conducted for lead in the Harkins Slough
waterway. Results from the three surface water
sample collected showed lead concentrations below
detectable limits.
In 2006, special funding by the Amphibian Initiative
of the U.S. Fish and Wildlife Service, Environmental
Contaminants Program was made available to
study amphibian abnormalities at the Ellicott and
Calabasas Ponds. The study coordinators were
especially interested in Ellicott Pond results, as
Ellicott Pond was one of the first sites to document
large numbers of abnormalities caused by trematode
parasites in the mid 1980s. The survey found that
the abnormal frog rates at Ellicott and Calabasas
Units were consistent with the expected background
abnormal rate of 2–3 percent in anuran populations
(Stocum 2000). The Refuge received funding again
in 2008 and 2009 for Calabasas Pond and found that
sampled rates were above the expected rate both
years (Tertes pers. comm.).
3.4 Biological Resources
3.4.1 Vegetation
Ellicott Slough NWR supports a variety of habitat
types. The habitat types are described in the
following sections. The habitat types on each of the
Refuge units and the Buena Vista property are shown
in the vegetation maps in Figures 6, 7, 8, and 9. A
summary table of acreages of the various habitat
types by unit is presented in Table 3. These acreages
are based on Geographic Information System (GIS)
analyses and satellite imagery with limited field
sampling, and therefore are general estimates.
The Refuge has a wide variety of plant communities
throughout its units. It has forests, woodlands,
shrublands, grasslands, and freshwater wetlands, to
name a few. Each habitat is important to maintain
a complex relationship of plants, animals, and other
organisms. The combination of habitats provides
breeding and non-breeding areas for threatened and
endangered amphibians, resident and migratory
birds, mammals of varying sizes, and many other
species. It also provides conditions suitable for
endangered, rare, native, and invasive trees, shrubs,
grasses, and forbs.


California's north coastal forests are divided into
separate communities that integrate with one
another. The largest and most important of these
communities are the coastal redwood, Douglas fir,
and mixed-evergreen forests. From the coast inland,
species composition is dictated by moisture gradients.
These gradients are determined by rainfall and the
ability of soils to retain water. In moderately moist
areas, farther inland, Douglas fir (Pseudotsuga
menziesii) becomes dominant. Mixed-evergreen
forests occur in warmer areas and are highly variable
in their species composition (CERES 1997).
Ecologists recognize at least 13 major tree
communities within California, and 5 of these
are associated with the coastal regions. There
are approximately 129 species of native trees in
California, 63 of which are endemic. It is estimated
that another 1,000 have been introduced from
all over the world, but most of these are limited
to private gardens. Nevertheless, about 30 to
50 introduced species have become naturalized,
including the ubiquitous blue gum, Eucalyptus
globulus (CERES 1997).
Closed-cone Coniferous Forests
Closed-cone coniferous forests are a unique
California community occurring in patches along
the coast from Humboldt to Santa Barbara County.
The name of this community derives from the
Ellicott Slough NWR - Final Comprehensive Conservation Plan 31
fact that the seed-bearing cones
remain closed for several years,
a reproductive adaptation that
ensures survival. Only age,
excessive hot weather, or fire
opens the cones (CERES 1997).
Douglas fir, Monterey pine
(Pinus radiata), and knobcone
pine (Pinus attenuata) grow
throughout the Refuge.
San Andreas Coastal Live
Oak Woodland
Coastal live oak woodland is
characterized by hilly slopes
with thin soils and moderate to
large amounts of rainfall. The
oak woodland present in Santa
Cruz County is locally referred
to as San Andreas Coastal Live
Oak Woodland. It is considered
a sensitive habitat by Santa Cruz
County because of its high species
diversity and relative scarcity (USFWS 2005a). Coast
live oak (Quercus agrifolia) dominates this habitat;
associated species include coffeeberry, madrone,
California blackberry (Rubus ursinus), creeping
snowberry, coyote bush (Baccharis pilularis), and
poison oak (Toxicodendron diversilobum).
Riparian Woodlands
Riparian woodlands occur in ribbon-like bands along
ephemeral creeks, ephemeral freshwater ponds, and
canyon bottoms (USFWS 2005a) where there are
rich soils and high humidity. Although this unique
community accounts for less than one per cent of
California's total forest acreage, it supports one of
the most diverse ecological communities of plants
and animals. Tall deciduous trees tower above a
lush understory of ferns and delicate wildflowers.
Unfortunately, many riparian woodlands have been
destroyed during the last century because the fertile
soils along rivers are among the most sought after
for agricultural lands and because numerous rivers
have been channelized for flood control projects
(CERES 1997).
Below the canopy of trees, rich riparian soils
support many species of ferns and willows such as
the goldenback fern (Pentagramma triangularis),
Arroyo willow (Salix lasiolepsis), and Sitka willow
(Salix sitchensis). California blackberry and
poison oak are frequently encountered shrubs in
riparian communities.
Eucalyptus Stands
The invasive blue gum (Eucalyptus spp.) can be
found in dense patches throughout the Refuge.
Because of the large amount of leaves, bark, and
other duff (and the tannins in them) that accumulate
below each eucalyptus tree, there is little to no
understory vegetation.
Acacia Stands
For the same reasons it is favored as an erosion-control
plant, with its easy spreading and resilience,
wattle (Acacia spp.) is an invasive species. Introduced
worldwide, it has become an invasive plant that
is taking over grasslands and the abandoned
agricultural areas, especially in moderate coastal
regions where mild climate propagates its spreading.
California's Coastal Plant Communities
Thirty percent of the state's native plant species
are endemic to California. Common endemic
plants include many species of manzanita and
monkeyflower. Ecologists recognize as many as 80
Coffeeberry. Photo: USFWS
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32 Ellicott Slough NWR - Final Comprehensive Conservation Plan
different plant communities, constituting what is
known as the California Floristic Province. Eleven
of these communities, of which six are non-tree
communities, are represented along the California
coast (CERES 1997).
Coastal Grasses
Until late in the last century, the coastal prairie
was almost entirely composed of native perennial
grasses. These relatively slow-growing grasses have
deep root systems and creeping stems that help to
ensure their long-term survival; some individual
plants are known to be more than 100 years old.
Early European settlers found the naturally
treeless coastal grasslands ideal for agriculture and
ranching. As grazing operations expanded, fast-growing,
invasive annual grasses were gradually
introduced, and these began to out-compete the
slow-growing, native perennials. Some introductions
were accidental and others were intentional. Annual
grasses live only a single growing season, but good
seed dispersal ensures their return year after year.
As a result, few intact native grassland communities
remain today (CERES 1997).
Representative native coastal grasses include
species of bentgrass (Agrostis spp.), hairgrass
(Deschampsia spp.), and oatgrass (Danathonia
spp.), which can all be found at Buena Vista.
However, the majority of grasses found at the
Refuge are invasive. Commonly encountered
invasive grasses include wild oat (Avena spp.),
fescue (Vulpia spp.), and brome (Bromus spp).
Ecologists believe that the presence of annual
grasses has actually increased the number of
wildflower species able to survive in this community
(CERES 1997). Miniature lupine (Lupinus bicolor),
California buttercup (Ranunculus californicus),
and the brilliant orange California poppy
(Eschscholzia californica) are common inhabitants
of the grassland community.
Coastal Scrub
Coastal scrub communities are characterized
by low shrubs and an absence of trees. Types of
shrubs include either pure stands or mixtures of
low, thick-leaved evergreens and coarse, deciduous
species that drop their leaves in response to periodic
drought conditions. Three representative scrub
assemblages (not strictly limited to the coast) are
the northern coastal scrub, southern coastal sage
scrub (or soft-chaparral), and arid hard-chaparral
(CERES 1997).
Northern Coastal Scrub
The Refuge has northern coastal scrub throughout
its units. Low, shrubby overstory and lush
herbaceous undergrowth often characterize the
northern coastal scrub community, which may
graduate into adjacent coastal prairie. Many
northern scrub species retain their leaves
throughout the year. Native coyote brush is the
most abundant plant in this community and is
easily identified by its white fall flowers. California
blackberry and poison oak are other common
shrubs. The predominantly gray-green northern
scrub landscape is accented by colorful sticky
monkeyflower (Mimulus aurantiacus), deerweed
(Lotus scoparius), and California lilac (Ceanothus
spp.) (CERES 1997).
San Andreas Maritime Chaparral
The San Andreas maritime chaparral is considered a
distinctive type of chaparral by Santa Cruz County
because of its unique species composition (USFWS
2005a). The chaparral community is dominated
by two species of manzanita: Hooker’s manzanita,
which is a rare species endemic to the Monterey
Bay region of Santa Cruz and Monterey Counties,
and wooly manzanita (Buena Vista Country Club,
Inc. 1995). This vegetation type is considered highly
restricted in distribution in California, with only 207
acres of San Andreas maritime chaparral remaining.
Buena Vista includes approximately 33 acres of
maritime chaparral.
Freshwater Marshes
Freshwater marsh plants have adapted to their
aquatic environment in several ways. Most species
have developed air tubes to their roots, buoyant
leaves, or porous leaf coverings that enhance gas
exchange. In contrast to salt marshes, freshwater
marshes have little, if any, water movement
(CERES 1997). Freshwater marshes can be found
throughout the Refuge.
Typical freshwater marsh plants include numerous
species of sedges; these grass-like plants often
Ellicott Slough NWR - Final Comprehensive Conservation Plan 33
exceed five feet in height. Sedge (Carex spp.) is
one of the most common. Familiar cigar-shaped
cattails (Typha latifolia) form thick stands and
are so prolific that a single plant can rapidly fill a
small pond. Bushy, needle-leaved rushes (Juncus
phaeocephalus) and succulent water parsley
(Oenanthe sarmentosa) are also typical freshwater
marsh inhabitants (CERES 1997).
Freshwater marsh can be found surrounding a
50-acre permanent pond at the Harkins Slough
Unit. The pond itself has only a few emergent plant
species, such as willows and invasive water hyacinth
(Eichhornia spp.).
Ephemeral Ponds
Seasonal freshwater ponds occur on Ellicott and
Calabasas Units and on the Buena Vista property.
The ponds tend to dry out during late summer.
The amount and duration of water retention is a
function of the amount and duration of rainfall
during the year (Buena Vista County Club, Inc.
1995). Common plant species include native cattails,
spikerush (Eleochris spp.), and invasive curly dock
(Rumex crispus).
Semi-natural Herbaceous Stands
In addition to invasive tree stands such as
eucalyptus and acacia mentioned previously,
there are also many invasive herbaceous plants
clumped in stands or occurring throughout most
plant communities at the Refuge. Common
species include poison hemlock, rosemary,
mustard, Himalayan blackberry, and pampasgrass
(Cortaderia selloana) and jubatagrass (C. jubata).
Threatened and Endangered
Plant Species
Robust Spineflower
Robust spineflower was Federally-listed as
endangered on February 4, 1994. It is currently
known from 10 sites that support a total of 12
populations (USFWS 2004a). It is restricted to
sandy soils along the coast and near-coastal areas in
Santa Cruz and Marin Counties. It is a short-lived
annual plant that germinates during the winter
months and generally flowers from April through
June. On the Refuge, it has been found on the
Ellicott Unit (with an estimated 5 acres of standing
plants) and at Buena Vista (10 acres). The species is
not currently actively managed by Refuge staff.
The robust spineflower relies on sandy soils
and coastal dune, coastal scrub, and grassland
communities. Spineflower can grow in sunny
openings within maritime chaparral and oak
woodland communities; however, these two
habitats themselves cannot support robust
spineflower because of shade and leaf litter.
Plants have been observed in disturbed areas
along trails and where gopher disturbance is high
(Baron, pers. comm.).
Populations of robust spineflower on Buena
Vista have been followed for more than a decade.
Available data are listed in Table 4 (CNDDB
1997, Baron, pers. comm.). On Buena Vista,
approximately 135 acres of this critical habitat were
designated for robust spineflower. The Ellicott Unit
population trends are unknown.
Robust Spineflower. Photo: Sandra Baron
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34 Ellicott Slough NWR - Final Comprehensive Conservation Plan
Table 4. Population counts for robust spineflower
on Buena Vista
Year Individuals Counted
1993 1,000
1997 1,000
2000 305
2003 3,700
3.4.2 Wildlife
Though the Watsonville Sloughs are a hydrologically
compromised system (see Geology, Soils, and
Hydrology in previous text), they are still
biologically rich and highly valued. It is one of the
largest remaining freshwater marshlands in the
California coastal zone, providing critical habitat for
numerous bird and plant species, including a variety
of rare and endangered species. Located along the
Pacific Flyway, it is an important rest stop, breeding
ground and year-round habitat for over 200 species
of waterfowl, songbirds, and raptors.
The many habitats of the Refuge provide homes for
a variety of wildlife. Many species are present on
the Refuge, including several amphibian, reptile,
waterfowl, waterbird, raptor, songbird, mammal,
invertebrate, and aquatic invertebrate species. The
primary species that are actively surveyed are the
Federally-listed amphibians. However, several
surveys have been conducted to start a baseline
account of birds and mammals. Incidental sightings
have also proved fruitful in adding wildlife to the
Refuge species list, such as medium and large
mammals and reptiles. Though the Refuge is known
for its amphibians, migratory birds use the Refuge
for a stopover on the Pacific Flyway, as well as for
roosting and nesting. Appendix F contains a list of
wildlife species that occur or potentially occur at the
Ellicott Slough NWR. An overview of wildlife use of
the Refuge follows.
Federally-listed Wildlife Species at the Refuge
Three Federally-listed wildlife species occur on the
Refuge: Santa Cruz long-toed salamander (SCLTS)
(Ambystoma macrodactylum croceum), listed as
endangered; the California tiger salamander (CTS)
(Ambystoma californiense), listed as threatened;
and the California red-legged frog (CRLF) (Rana
aurora draytonii), listed as threatened. Habitat
for these species range-wide is continually reduced
due to development, resulting in fragmented areas,
especially between salamander over-summering
(upland) habitat and breeding grounds (pond).
Furthermore, it is difficult to track productivity of
these species because they spend most of their time
over-summering underground and only migrate
during rainy nights. In addition to conducting
night time surveys in the winter, surveys are also
conducted in late spring to determine if reproduction
has occurred. These larval surveys are conducted for
presence or absence, health, and fitness.
Table 5. Santa Cruz long-toed salamander subpopulation complexes
Santa Cruz metapopulation
Valencia-Seascape Valencia Lagoon and Seascape Ponds and surrounding upland habitat
Larkins Valley Calabasas, Suess, and Olive’s Ponds and surrounding upland habitat
Ellicott-Buena Vista Ellicott, Buena Vista, Ranch Road, Green’s and Anderson’s Ponds and sur-rounding
upland habitat
Freedom Palmer, Racehorse, Tucker, Merk, and Millsap Ponds and surrounding upland
habitat
Monterey metapopulation
McClusky Zmudowski Pond, Bennett Slough/Struve Pond, McCluskey Slough and sur-rounding
habitat
Elkhorn Oxbow Pond, Lower Cattail Swale, Northern Moro Cojo and Southern Moro
Cojo Sloughs and surrounding upland habitat
Source: Santa Cruz Long-toed Salamander 5-Year Review (USFWS 2009)
Ellicott Slough NWR - Final Comprehensive Conservation Plan 35
Santa Cruz Long-toed Salamander
SCLTS was among the first animals listed as
endangered by the Service in 1967 due to several
factors, most prominently habitat loss and
fragmentation. At the time, only two breeding
localities of the species, Valencia Lagoon and
Ellicott Slough, were known. The presence of the
SCLTS has been documented at only 24 locations
in southern Santa Cruz County and northern
Monterey County. Breeding has been documented
at 19 of the 24 known locations since the last revised
recovery plan for the subspecies (USFWS 1999b)
was published. The subspecies likely has been
extirpated from two locations: Bennett Slough/
Struve Pond in Monterey County and Rancho
Road Pond in Santa Cruz County. It is not known
whether two other previously known breeding
locations (Green’s Pond and Anderson’s Pond)
in Santa Cruz County still exist. Additionally,
breeding has not been documented at Lower
Moro Cojo Slough (in Monterey County) since
1990 (USFWS 2009). This species was added
to California’s endangered species list in 1971,
with additional protections under the Santa Cruz
Local Coastal Plan and the Santa Cruz County
Salamander Protection District zoning regulations.
SCLTS are found in six metapopulations, four
of which are located in Santa Cruz County and
two of which are located in Monterey County.
Each metapopulation contains one or more
subpopulations. Metapopulations found in Santa
Cruz County include Valencia-Seascape, Freedom,
Larkin Valley, and Ellicott-Buena Vista while
metapopulations found in Monterey County include
McCluskey and Elkhorn (see Table 5). The Ellicott
Unit, Harkins Slough Unit, and Buena Vista
property are located within the Ellicott-Buena
Vista metapopulation and the Calabasas Unit of
the Refuge is located within the Larkin Valley
metapopulation (USFWS 2009). There is no single
comprehensive population estimate available, and
only sporadic surveys have been conducted on some
parts of some subpopulations. For the purposes of
this CCP, data and management of only the Larkins
Valley and Ellicott-Buena Vista complexes will be
discussed. The Refuge provides both breeding
(ponds) and over-summering (upland) habitat for
SCLTS.
The Larkins Valley complex lies in the upper
Harkins Slough watershed. The Refuge’s Calabasas
Pond is located in the Larkins Valley complex and
is considered a breeding site. The current size and
status of this salamander subpopulation is unknown,
but surveys have documented reproduction in 1989,
1993, 1995, and 2004–2010 (USFWS 1999b, Tertes
pers. comm. 2010).
SCLTS rely on freshwater ponds for egg
development, where larvae feed and grow in the
pond for three to seven months before becoming
terrestrial. Insufficient precipitation, unusually
cold weather, parasites, or other unknown factors
may severely limit recruitment. Adults may go
several years without successfully breeding. SCLTS
Santa Cruz long-toed salamander larvae. Photo: USFWS
Adult Santa Cruz long-toed salamander. Photo: Leah Oscar
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36 Ellicott Slough NWR - Final Comprehensive Conservation Plan
apparently are long-lived creatures, possibly living
for a decade or more (USFWS 2009).
The primary terrestrial habitats for SCLTS are oak
woodland, woody riparian, and moist coastal scrub
vegetation types. SCLTS spend the majority of
their life in these terrestrial habitats, underground
in small mammal burrows and among the root
systems of plants in upland chaparral and woodland
areas of coast live oak or Monterey pine, as well as
in riparian strips of arroyo willows. These areas
are desirable because they are protected from heat
and the drying rays of the sun. From November
to February, their annual nocturnal migration to
the breeding ponds occurs. The breeding ponds
are usually shallow and ephemeral freshwater
ponds; however, most ponds currently known to be
used for breeding are artificial. The extent of the
upland habitat potentially used by SCLTS varies
from a ring of riparian vegetation on the perimeter
of the pond to as far as one mile or more out from
the pond. However, examination of all currently
available studies on SCLTS reveals that no adults
have been observed to move more than 0.6 mile
(straight line distance) from a breeding site where
they were originally marked. The distance between
known breeding and over-summering locations
varies greatly from site to site and apparently
depends largely upon soil type, vegetation presence
or absence, vegetation structure or composition,
and slope, aspect, and size of the breeding pond
(USFWS 2009).
The Ellicott Slough-Buena Vista complex contains
five ponds that have been used as breeding
habitat by SCLTS. Breeding activity has been
documented at the other sites in the vicinity since
1993. The Ellicott Pond population was surveyed
from 1956–1960, and it was estimated that there
were 8,000–10,000 individuals (USFWS 1999b). A
population estimate was also conducted during
1972–1973, yielding an estimated 6,000–8,000
individuals (Marlow 1973). A survey from 1979–1980
indicated that Ellicott Pond was used for breeding.
Approximately 345 adults were found migrating
to the pond for the breeding season (Reed 1979).
Juveniles were also seen moving away from the
pond, indicating successful recruitment. Since then,
regular monitoring has documented the presence of
salamanders in most years between 1992 and 2010
(USFWS 1999b, Tertes pers. comm. 2010). Survival
of the Ellicott population was threatened in 1970
when the owner of the breeding site and much of
the upland attempted to rezone the area for a trailer
park (Bury and Ruth 1972).
The Buena Vista Pond was created during the 1940s,
and SCLTS were first found here in 1992. It may
support several hundred adults, based on trapping
studies conducted during 1995 (Jennings 1995). An
additional mark-recapture study was conducted by
Biosearch Associates in the winter of 2008–2009.
They estimated the breeding adult population of
SCLTS at Buena Vista Pond to be 775, with a 95
percent confidence interval of ± 380 due to low
number of recaptures. However, due to a shortage
of rainfall and therefore a shortened hydro-period,
breeding migration was affected and the population
size has probably been underestimated (Biosearch
Associates 2009). The hydro-period is the duration of
time an ephemeral pond will retain water.
The SCLTS continues to face numerous threats,
including loss and degradation of both upland
and breeding habitats from proposed residential
development, road kill, encroachment of agricultural
activities and invasive plant and animal species,
sedimentation, and degraded water quality.
Disjunct distributions have made SCLTS especially
susceptible to population declines resulting from
human-associated factors such as habitat loss.
Degradation and destruction of aquatic breeding
habitat was the primary reason for listing this
species. In Santa Cruz County, the primary threats
have been road construction and urbanization.
Other threats include predators such as invasive
opossums (Didelphis virginiana), striped skunks
(Mephitis mephitis), raccoons (Procyon lotor), and
a variety of snakes. Further details of life history
and biology of the SCLTS are contained in the
revised Recovery Plan (USFWS 1999b). Although
the SCLTS is now known from more locations than
when it was listed and some sites are now protected,
the overall status of the SCLTS remains tenuous.
California Tiger Salamander
The CTS, listed as threatened in August 2004,
inhabits large ephemeral pools and their
surrounding grasslands throughout the Central
Valley as well as adjacent foothill and coastal
grasslands. It is the only native tiger salamander
species known to occur in its range. It is estimated
Ellicott Slough NWR - Final Comprehensive Conservation Plan 37
that 75 percent of the original CTS habitat is now
lost due to anthropogenic impacts and that 55 to 58
percent of documented historic breeding sites has
been eliminated (USFWS 2004).
The CTS life history is similar to the SCLTS,
requiring shallow ephemeral ponds for breeding in
the winter months. During the summer months,
CTS persist in open grasslands, using ground
squirrel and pocket gopher burrows, as well as deep
cracks or holes in the ground, for over-summering.
CTS have been demonstrated to remain active
throughout the summer, moving small distances
within burrow systems. Dispersal distances from
pond breeding sites to upland burrows depend
on local topography and vegetation, distribution
of burrows, and climatic conditions. CTS require
different over-summering habitat from the SCLTS.
CTS prefer grassland, whereas Santa Cruz long-toed
salamanders prefer oak woodland.
Both breeding and over-summering habitat for CTS
are provided at the Ellicott Unit and the Buena
Vista property. Regular monitoring has documented
the presence of salamanders in most years between
1993 and 2010 at Ellicott Pond (Tertes pers. comm.
2010). However, breeding and non-breeding habitat
use has not been thoroughly assessed at the Refuge.
In the winter of 2008–2009, two adult female and 11
adult male CTS were captured at the Buena Vista
Pond during a mark-recapture study performed
by Biosearch Associates. Biosearch estimated the
breeding adult population of CTS at Buena Vista
Pond to be 16, with a 95 percent confidence interval
of ± 10. However, due to a shortage of rainfall
and therefore a shortened hydro-period, breeding
migration was affected, and the population size
has probably been underestimated (Biosearch
Associates 2009). During the study, Biosearch
also sent CTS tissue for genetic testing. Results
verified the salamander as the native CTS—and
not a hybrid. (Biosearch Associates 2009). There
have been no CTS population studies conducted at
Ellicott Pond; however, CTS have been found during
rainy night-time surveys at Ellicott Unit (Tertes,
pers. comm. 2010). Therefore, while the Ellicott
Unit and Buena Vista have breeding CTS, there is
currently no population estimate.
California Red-legged Frog
The CRLF was listed as a threatened species on
June 24, 1996. It is also listed as a state species
of concern. The CRLF has been extirpated or
nearly extinct from 70 percent of its former range.
Habitat loss and alteration, combined with over-exploitation
and introduction of invasive predators,
were important factors in the decline of the CRLF
in the early to mid-1990s. Primary threats that led
to its listing status included urban encroachment,
construction of reservoirs and water diversions,
contaminants, agriculture, and livestock grazing
(USFWS 2002). At present, CRLF are known to be
present in approximately 256 streams or drainages
from 28 counties, primarily in central coastal
California (USFWS 2002).
CRLFs breed from November through April.
California red-legged frogs spend most of their
lives in and near sheltered backwaters of ponds,
marshes, springs, streams, and reservoirs. Deep
pools with dense stands of overhanging willows
and an intermixed fringe of cattails are considered
optimal habitat. California red-legged frog eggs,
larvae, transformed juveniles, and adults also have
been found in ephemeral creeks and drainages and
in artificial ponds devoid of riparian or wetland
vegetation. Each of the life stages also have been
observed in artificial environments, such as stock
ponds, sewage treatment ponds, irrigation ponds,
wells, canals, golf course ponds, sand and gravel
pits, and large reservoirs (USFWS 2002).
Accessibility to sheltering habitat is essential for the
survival of CRLF within a watershed and may be a
factor limiting population numbers and distribution.
Juvenile and adult CRLF have been observed in
areas of riparian vegetation where they may use
small mammal burrows, moist litter, and debris
such as discarded lumber (boards on the ground)
California tiger salamander juvenile. Photo: Heather Butler
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38 Ellicott Slough NWR - Final Comprehensive Conservation Plan
for sheltering. During wet periods (particularly
winter and spring), CRLF may move long distances
between aquatic habitats, often traveling through
habitats previously considered to be unsuitable
for frogs. California red-legged frogs have been
found more than one mile from breeding habitat
and may reach isolated aquatic habitats up to a mile
away from the nearest known CRLF populations
(USFWS 2002).
The Refuge falls into one of the recovery units for
this species. Critical habitat has also been designated
at Ellicott and Harkins Slough Units and the Buena
Vista Property (USFWS 2010). However, breeding
and non-breeding habitat use by the CRLF has never
been thoroughly assessed at the Refuge. Therefore,
the current status and size of the population at the
Refuge is unknown. There have been anecdotal
reports that CRLF have been heard calling at pond
at the Ellicott Unit; however, no larvae have been
found in the pond. Pond surveys at the Calabasas
Unit indicated presence of California red-legged frog
larvae once in the past 10 years. Ongoing threats,
which are primarily the result of urbanization
and agricultural activities, include habitat loss,
fragmentation, and degradation and establishment of
invasive vegetation, disease, and predators.
Other Wildlife
Amphibians and Reptiles
In addition to the special status amphibians, a
variety of other native amphibian species have been
found on the Refuge, including California slender
salamander (Batrachoseps attenuatus) and arboreal
salamander (Aneides lugubris). Pacific tree frogs
are most commonly seen in or adjacent to seasonal
and permanent waterbodies, while other amphibians
are more commonly seen during terrestrial night-time
surveys. Some species found during these
surveys include ensatina salamander (Ensatina
eschscholtzii), arboreal salamander, California
slender salamander, and Pacific tree frog (see
Appendix F).
Reptiles are common residents in the upland,
riparian, and wetland habitats. Reptile species
recorded during coverboard surveys include western
fence lizard (Sceloporus occidentalis), southern
alligator lizard (Elgaria multicarinata), and
western skink (Eumeces skiltonianus). Additional
sightings by Refuge personnel during tree removal
work, plantings, and surveys include ringneck snake
(Diadophis punctata), racer (Coluber constricta),
gopher snake (Pituophis melanoleuca), common
garter snake (Thamnophis sirtalis), and Western
terrestrial garter snake (Thamnophis elegans). A
list of wildlife species is included in Appendix F.
Mammals
Many mammalian species are year-round residents
of the Refuge. A small mammal trapping study in
1977 by CDFG was the first inventory of mammal
species on t