Natural Resource Management Plan for Mission Trails Regional Park San Diego, California

304 Pages·2017·42.05 MB·English

Natural Resource Management Plan
for Mission Trails Regional Park
San Diego, California
City of San Diego
Park & Recreation Department
202 C Street, MS5D
San Diego, CA 92101
Natural Resource
Management Plan
for Mission Trails
Regional Park,
San Diego, California

Prepared for Prepared by

City of San Diego RECON Environmental, Inc.
Parks & Recreation Department 1927 Fifth Avenue
202 C Street,MS5D San Diego, CA 92101-2358
San Diego, CA 92101 P 619.308.9333 F 619.308.9334
RECON Number 5286
January 17, 2017
Mission Trails Regional Park NRMP Table of Contents
TABLE OF CONTENTS
Acronyms vii
1.0 Introduction 1-1
2.0 Existing Conditions 1
2.1 Environmental Setting 1
2.1.1 Topography 2-1
2.1.2 Geology and Paleontology 2-1
2.1.3 Soils 2-5
2.1.4 Hydrology 2-6
2.2 Existing Biological Resources 2-10
2.2.1 Vegetation Communities 2-10
2.2.2 Plant Species 2-13
2.2.3 Wildlife Species 2-13
2.2.4 Wildlife Corridors 2-28
3.0 Regulatory Framework 3-1
3.1 Multiple Species Conservation Program 3-1
3.2 Multi-Habitat Planning Area Guidelines for MTRP 3-1
4.0 Biological Resource Management 4-1
4.1 Sensitive Biological Resources 4-1
4.1.1 Sensitive Species within MTRP 4-1
4.2 Threats to Biological Resources at MTRP 4-1
4.2.1 Preserve-level Threats 4-6
4.2.2 Region-wide Threats 4-9
4.3 Adaptive Management 4-12
4.3.1 Management Action Tool Kit 4-12
4.3.2 Management Prioritization 4-13
4.4 Priority Species Management at MTRP 4-15
4.4.1 San Diego Thornmint (Acanthomintha ilicifolia) 4-15
4.4.2 San Diego Ambrosia (Ambrosia pumila) 4-26
4.4.3 Variegated Dudleya (Dudleya variegata) 4-39
4.4.4 Willowy Monardella (Monardella viminea) 4-53
4.4.5 Coastal Cactus Wren (Campylorhynchus brunneicapillus couesi) 4-67
4.5 Priority Management Guilds at MTRP 4-77
4.5.1 Cliffs and Rocky Outcrops 4-77
4.5.2 East Elliott Clay Ridgelines 4-86
4.5.3 Tierrasanta Clay Ridge 4-95
4.5.4 Riparian Woodlands 4-102
4.5.5 Coastal Sage Scrub – Artemisia/Eriogonum 4-109
5.0 Budget and Schedule 5-1
6.0 References 6-1
i
Mission Trails Regional Park NRMP Table of Contents
FIGURES
2-1: Regional Location of Mission Trails Regional Park 2-2
2-2: Mission Trails Regional Park Areas 2-3
2-3: Topography within Mission Trails Regional Park 2-4
2-4: Soil Types Present within Mission Trails Regional Park 2-7
2-5: Soil Types Associated with Sensitive Species Occurrences Present within
Mission Trails Regional Park 2-8
2-6: Hydrologic Units Present within Mission Trails Regional Park 2-9
2-7a: Vegetation Communities at MTRP (Holland Code) 2-14
2-7b: Vegetation Communities at MTRP (Holland Code) 2-15
2-7c: Vegetation Communities at MTRP (Holland Code) 2-16
2-7d: Vegetation Communities at MTRP (Holland Code) 2-17
2-7e: Vegetation Communities at MTRP (Holland Code) 2-18
2-8a: Vegetation Communities at MTRP (SANDAG) 2-23
2-8b: Vegetation Communities at MTRP (SANDAG) 2-24
2-8c: Vegetation Communities at MTRP (SANDAG) 2-25
2-8d: Vegetation Communities at MTRP (SANDAG) 2-26
2-8e: Vegetation Communities at MTRP (SANDAG) 2-27
2-9: Regional Wildlife Corridors at Mission Trails Regional Park 2-31
2-10: Preserve Level Connectivity within Mission Trails Regional Park 2-32
2-11: Wildlife Crossings at Mission Trails Regional Park 2-33
3-1: Project in Relation to MSCP Preserve Area 3-3
4-1: Approximate Location of Utility and Service Lines within
Mission Trails Regional Park 4-11
4-2: San Diego Thornmint (Acanthomintha ilicifolia) Detected Occurrences:
Mission Trails Regional Park 4-18
4-3: Comparison of Purple False Brome (BRDI) and Other Non-Native
Species Cover at Area D Over Time 4-20
4-4: Conceptual Model for San Diego Thornmint (Acanthomintha ilicifolia)
at MTRP 4-22
4-5: San Diego Thornmint (Acanthomintha ilicifolia) Management Actions:
Mission Trails Regional Park 4-24
4-6: San Diego Ambrosia (Ambrosia pumila) Detected Occurrences:
Mission Trails Regional Park 4-29
4-7: San Diego Ambrosia Population Area at MTRP Occurrence C 4-31
4-8: Conceptual Model for San Diego Ambrosia (Ambrosia pumila) at MTRP 4-33
4-9a: San Diego Ambrosia (Ambrosia pumila) Management Actions:
Mission Trails Regional Park 4-34
4-9b: San Diego Ambrosia (Ambrosia pumila) Management Actions:
Mission Trails Regional Park 4-35
4-9c: San Diego Ambrosia (Ambrosia pumila) Management Actions:
Mission Trails Regional Park 4-36
ii
Mission Trails Regional Park NRMP Table of Contents
FIGURES (cont.)
4-10a: Variegated Dudleya (Dudleya variegata) Detected Occurrences:
Mission Trails Regional Park 4-40
4-10b: Variegated Dudleya (Dudleya variegata) Detected Occurrences:
Mission Trails Regional Park 4-41
4-10c: Variegated Dudleya (Dudleya variegata) Detected Occurrences:
East Elliott 4-42
4-10: Three Selected Populations of Variegated Dudleya within the
Fortuna Mountain Area 4-44
4-11: Three Selected Populations of Variegated Dudleya within the
East Elliott Area 4-44
4-13a: Variegated Dudleya (Dudleya variegata) Management Actions:
Mission Trails Regional Park 4-47
4-13b: Variegated Dudleya (Dudleya variegata) Management Actions:
Mission Trails Regional Park 4-48
4-13c: Variegated Dudleya (Dudleya variegata) Management Actions:
East Elliott 4-49
4-14: Conceptual Model for Variegated Dudleya (Dudleya variegata) at MTRP 4-51
4-15: Population Size (clumps vs. plants) of Willowy Monardella at
Occurrence A within the West Sycamore Area 4-55
4-16: Clump to Individual Ratio of Willowy Monardella at Occurrence A at
West Sycamore Area 4-56
4-17a: Willowy Monardella (Monardella viminea) Detected Occurrences:
West Sycamore 4-57
4-17b: Willowy Monardella (Monardella viminea) Detected Occurrences:
East Elliott 4-58
4-18: Conceptual Model for Willowy Monardella (Monardella viminea) at MTRP 4-61
4-19a: Willowy Monardella (Monardella viminea) Management Actions:
West Sycamore 4-63
4-19b: Willowy Monardella (Monardella viminea) Management Actions:
East Elliott 4-64
4-20: San Diego Cactus Wren (Campylorhynchus brunneicapillus couesi)
Detected Occurrences: West Sycamore 4-70
4-21: San Diego Cactus Wren (Campylorhynchus brunneicapillus couesi)
and Cacti: Regional Habitat Connectivity 4-71
4-22: Conceptual Model for Coastal Cactus Wren
(Campylorhynchus brunneicapillus cousei) at MTRP 4-73
4-23: San Diego Cactus Wren (Campylorhynchus brunneicapillus couesi)
Management Actions: West Sycamore 4-74
4-24: Cliffs and Rocky Outcroppings within Mission Trails Regional Park 4-81
4-25: Conceptual Model for Cliffs and Rocky Outcrops Management Guild 4-83
4-26: Cliff and Rocky Outcroppings Guilds Management Action:
Mission Trails Regional Park 4-85
4-27: East Elliott Clay Ridgeline Guild within Mission Trails Regional Park 4-88
4-28: Conceptual Model for East Elliot Clay Ridgeline Management Guild 4-91
4-29: East Elliott Clay Ridgeline Guild Management Actions 4-92
4-30: Tierrasanta Clay Guild Presence within Mission Trails Regional Park 4-97

iii
Mission Trails Regional Park NRMP Table of Contents
FIGURES (cont.)
4-31: Conceptual Model for Tierrasanta Clay Ridge Management Guild 4-99
4-32: Tierrasanta Clay Guild Management Actions:
Mission Trails Regional Park 4-101
4-33: Riparian Woodland Presence within Mission Trails Regional Park 4-103
4-34: Conceptual Model for Riparian Woodlands Management Guild 4-107
4-35a: Coastal Sage Scrub (Artemisia/Eriogonum) Guild within
Mission Trails Regional Park 4-110
4-35b: Coastal Sage Scrub (Artemisia/Eriogonum) Guild within
Mission Trails Regional Park 4-111
4-35c: Coastal Sage Scrub (Artemisia/Eriogonum) Guild within
East Elliott 4-112
4-35d: Coastal Sage Scrub (Artemisia/Eriogonum) Guild within East Elliott 4-113
4-35e: Coastal Sage Scrub (Artemisia/Eriogonum) Guild within East Elliott 4-114
4-35f: Coastal Sage Scrub (Artemisia/Eriogonum) Guild within East Elliott 4-115
4-36a: California Gnatcatcher Habitat Evaluation Model Spring 2003 (pre-fire) 4-117
4-36b: California Gnatcatcher Habitat Evaluation Model Spring 2003 (pre-fire) 4-118
4-37a: California Gnatcatcher Habitat Evaluation Model 2010 (post fire) 4-119
4-37b: California Gnatcatcher Habitat Evaluation Model 2010 (post fire) 4-120
4-38a: Change in California Gnatcatcher Habitat Evaluation Model 2003-2010 4-121
4-38b: Change in California Gnatcatcher Habitat Evaluation Model 2003-2010 4-122
4-39: Coastal Sage Scrub (Artemisia/Eriogonum) Guild Management Actions 4-126
4-40: Conceptual Model for Coastal Sage Scrub (Artemisia/ Eriogonum)
Management Guild 4-128
PHOTOGRAPHS
4-1: San Diego thornmint within a clay lens at MTRP 4-16
4-2: Degraded San Diego thornmint habitat on friable clay lens within the
Fortuna Mountain sub-area within MTRP. Note invasion of purple false
brome (light green grass between shrubs) 4-16
4-3: San Diego ambrosia at MTRP 4-27
4-4: San Diego ambrosia habitat within the Mission Gorge area, facing north 4-28
4-5: Willowy monardella within the West Sycamore area at MTRP 4-54
4-6: Willowy monardella habitat within the East Elliott area of MTRP 4-55
4-7: Coastal cactus wren habitat within the West Sycamore subarea of MTRP 4-69
4-8: Visitor Center Loop quarry cliff face, MTRP, facing northwest 4-78
4-9: West Kwaay Paay rocky outcropping, MTRP, facing northeast 4-79
4-10: Detail of soil crusts within East Elliott Clay Ridgeline Guild at MTRP 4-87
4-11: Vegetation present within the Tierrasanta Clay Ridge
Management Guild boundary 4-96
4-12: Habitats present within the Riparian Woodland Guild at MTRP 4-104
4-13: Artemisia californica-dominated scrub at MTRP 4-116
4-14: Artichoke thistle infestation within the West Sycamore Subarea 4-127
iv
Mission Trails Regional Park NRMP Table of Contents
TABLES
2-1: Geologic Formations with High Paleontological Sensitivity within MTRP 2-5
2-2: Baseline Data Collection at MTRP 2-11
2-3: Holland Vegetation Communities and Land Cover Types within MTRP 2-12
2-4: SANDAG Vegetation Groups within MTRP 2-12
2-5: SANDAG Vegetation Community Alliance and Associations
Observed at MTRP 2-19
2-6: Preserve Level Adjacency to Open Space at MTRP 2-29
2-7: Wildlife Undercrossings at SR-52 2-30
4-1: Sensitive Plant Species Observed within MTRP 4-2
4-2: Sensitive Wildlife Species Observed within MTRP 4-3
4-3: MSCP Covered Species, Required Area Specific Management Directives
(ASMDs), and Associated Sections within The MTRP NRMP 4-4
4-4: Priority Sensitive Species at MTRP 4-14
4-5: Priority Management Guilds at MTRP 4-14
4-6: Size of Population D Over Time 4-17
4-7: Size of Populations A and B Over Time 4-19
4-8: Variegated Dudleya Location Parcel Ownership within MTRP 4-43
4-9: Variegated Dudleya Surveys on Selected Sites within MTRP (2001-2012) 4-43
4-10: Channel Entrenchment Classifications 4-65
4-11: CWMA Cacti Height Classes 4-76
4-12: Sensitive Species Observed within the Cliffs and Rocky Outcropping
Management Guild at MTRP 4-80
4-13: Sensitive Species within the East Elliott Clay Ridgeline Management Guild 4-87
4-14: East Elliott Clay Ridgeline Survey: Sensitive Species Targets 4-93
4-15: Sensitive Species Observed within Tierrasanta Clay Ridge
Management Guild at MTRP 4-96
4-16: Sensitive Species Observed within Riparian Woodlands at MTRP 4-105
4-17: Sensitive Species Observed within the Coastal Sage Scrub –
Artemisia/Eriogonum Guild at MTRP 4-116
4-18: Acreage of High and Very High California Gnatcatcher at MTRP 4-123
4-19: Major Wildfires within Coastal Sage Scrub - Artemisia/Eriogonum
Guild Boundaries at MTRP 4-124
5-1: Budget and Schedule 5-1
APPENDICES
A-A: Plant Species Observed within MTRP
A-B: Wildlife Species Observed/Detected within MTRP during 2009/10 Surveys
A-C: Sensitive Species at MTRP not Selected for Individual Management
A-D: Fire Management Plan
v
Acronyms
Acronyms
ASMD Area-specific Management Directives
Cal-IPC California Invasive Plant Council
Caltrans California Department of Transportation
CDFW California Department of Fish and Wildlife
City City of San Diego
CNDDB California Natural Diversity Database
CNPS California Native Plant Society’s
CWA Clean Water Act
CWMA Cactus Wren Management Area
EO Elemental Occurrence
GIS Geographic Information System
GPS Global Positioning System
JURMP Jurisdictional Urban Water Runoff Management Plan
MBTA Migratory Bird Treaty Act
MCAS Marine Corps Air Station
MHPA Multi-Habitat Planning Area
MDP Master Development Plan
MPU Master Plan Update
MSCP Multiple Species Conservation Program
MSP Management Strategic Plan
MSS Maritime Succulent Scrub
MTRP Mission Trails Regional Park
NAS National Academy of Sciences
NRMP Natural Resource Management Plan
RWQCB Regional Water Quality Control Board
SANDAG San Diego Association of Governments
SDCWA San Diego County Water Authority
SDG&E San Diego Gas & Electric
SDMMP San Diego Management and Monitoring Program
SDNHM San Diego Natural History Museum
SDSU San Diego State University
SR-52 State Route 52
USACE U.S. Army Corps of Engineers
USDA U.S. Department of Agriculture
USFWS U.S. Fish and Wildlife Service
USGS U.S. Geological Survey
WMA Weed Management Area
WNS White-Nose Syndrome
WTI Western Tracking Institute

vi
Mission Trails Regional Park NRMP 1.0 Introduction
1.0 Introduction
This Natural Resource Management Plan (NRMP) fulfills the City of San Diego’s (City)
Multiple Species Conservation Program (MSCP) requirement to develop Area-Specific
Management Directives (ASMDs) for the protection of natural resources at Mission Trails
Regional Park (MTRP) (see MSCP Implementing Agreement Section 10.6.B, City
Subarea Plan Section 1.5.6, and Final MSCP Plan Section 6.3). MTRP is a core
biological area and regional wildlife corridor within the MSCP’s Multi-Habitat Planning
Area (MHPA) and is managed to achieve the goals of the MSCP. The specific objectives
of the NRMP are to:
• Update sensitive species and habitat mapping.
• Develop management guilds (management units based on habitat groupings with
similar life-history requirements and/or threats) for groups of species and/or
habitats.
• Identify and prioritize threats to sensitive species and habitats.
• Document current understanding of natural systems and species life history
requirements using conceptual models.
• Develop conservation and enhancement goals for individual populations/habitats
and/or management guilds based on MSCP conditions of coverage (MSCP Plan
Table 3-5).
• Develop specific management actions (e.g., ASMDs) within an adaptive
management framework to address the identified threats and ensure long-term,
viable populations of these species within MTRP.
• Develop protocols (e.g., data collection methods, success criteria) to evaluate
adaptive management techniques and projects proposed in this plan.
Page 1-1
Mission Trails Regional Park NRMP 2.0 Existing Conditions
2.0 Existing Conditions
2.1 Environmental Setting
The MTRP planning envelope occupies a total of 9,780 acres and is located eight miles
northeast of the City’s downtown (Figure 2-1). MTRP supports a wide range of native
vegetation, habitats, and wildlife species within a diverse physical setting, and is a core
biological resource area within the MHPA. MTRP has multiple notable features, including
Cowles and Fortuna mountains, the San Diego River, Sycamore Landfill, Lake Murray,
Mission Gorge, and the Old Mission Dam. For planning and discussion purposes, MTRP
has been divided into six areas based on significant features of each. The designated
areas are shown on Figure 2-2 and are:
 Lake Murray
 Cowles Mountain
 Mission Gorge
 Fortuna Mountain
 East Elliott
 West Sycamore
MTRP is a regionally important recreation area for many outdoor sports, including:
hiking, mountain biking, horseback riding, and rock climbing. The trails provide access
for recreational and maintenance activities Trails are generally 2–4 feet in width, except
where co-located with access roads. The existing trail system at MTRP is currently being
reevaluated and revised in the Master Plan update associated with this NRMP.
2.1.1 Topography
MTRP contains a variety of topographic features, including canyons, valleys, mountains,
hills, and low-lying areas. The topography is generally very rugged, with elevations
ranging dramatically throughout the different areas. Cowles Mountain is the highest point
in MTRP at 1,591 feet (Figure 2-3).
2.1.2 Geology and Paleontology
Geologically, the region of San Diego County in which MTRP is located consists of a
layer cake sequence of Cenozoic sedimentary rock units which preserve portions of the
last 47 million years of Earth history. These Cenozoic sedimentary rocks overlie a deeply
eroded terrain formed in significantly older crystalline basement rocks (e.g.,
metasediments, metavolcanics, gabbros, granites, and tonalities) of the massive
Peninsular Ranges Batholith.
Page 2-1