4.0 CONSERVATION AN TABLE OF CONTENTS 4.0 CONSERVATION ANALYSIS ............................................................................................ 4-1 4.1 PURPOSE ..................................................................................................................... 4-1 4.2 RESERVE DESIGN PRINCIPLES .............................................................................. 4-2 4.3 CONSERVATION ANALYSIS BY NATURAL COMMUNITY .............................. 4-6 4.3.1 Landscape Level Key Conservation Elements ................................................. 4-6 4.3.1.1 Corridors ......................................................................................... 4-7 4.3.1.2 Rarity-Weighted Richness Index .................................................... 4-8 4.3.1.3 Climate Change ............................................................................... 4-9 ALYSIS 4.3.2 Valley Floor Grassland and Vernal Pools ...................................................... 4-11 4.3.2.1 Associated Covered Species and Special Management Species .......................................................................................... 4-12 4.3.2.2 Key Conservation Elements .......................................................... 4-12 4.3.2.3 Conservation Areas ....................................................................... 4-17 4.3.3 Inner Coast Range .......................................................................................... 4-20 4.3.3.1 Associated Covered and Special Management Species ................ 4-20 4.3.3.2 Key Conservation Elements .......................................................... 4-21 4.3.3.3 Conservation Areas ....................................................................... 4-24 4.3.4 California Red-Legged Frog .......................................................................... 4-26 4.3.4.1 Associated Natural Communities, Covered Species, and Special Management Species ........................................................ 4-27 4.3.4.2 Key Conservation Elements .......................................................... 4-27 4.3.4.3 Conservation Areas ....................................................................... 4-30 4.3.5 Callippe Silverspot Butterfly .......................................................................... 4-30 4.3.5.1 Associated Natural Communities, Covered Species and Special Management Species ........................................................ 4-30 4.3.5.2 Key Conservation Elements .......................................................... 4-30 4.3.5.3 Conservation Areas ....................................................................... 4-31 4.3.6 Riparian, Stream, and Freshwater Marsh Natural Community ...................... 4-31 4.3.6.1 Associated Covered Species and Special Management Species .......................................................................................... 4-31 4.3.6.2 Key Conservation Elements .......................................................... 4-32 4.3.6.3 Conservation Areas ....................................................................... 4-37 4.3.7 Giant Garter Snake ......................................................................................... 4-40 4.3.7.1 Associated Natural Communities, Covered Species, and Special Management Species ........................................................ 4-40 4.3.7.2 Giant Garter Snake Habitat Model ................................................ 4-40 4.3.7.3 Conservation Areas ....................................................................... 4-42 4.3.8 Coastal Marsh ................................................................................................ 4-42 4.3.8.1 Associated Covered Species and Special Management Species .......................................................................................... 4-43 4.3.8.2 Conservation Background ............................................................. 4-43 4.3.8.3 Key Conservation Elements .......................................................... 4-44 4.3.8.4 Conservation Areas ....................................................................... 4-46 4.3.9 Swainson's Hawk ........................................................................................... 4-47 4.3.9.1 Associated Covered Species and Special Management Species .......................................................................................... 4-47 4-i Oct 2012 4.3.9.2 Key Conservation Elements.......................................................... 4-47 4.3.9.3 Conservation Areas ....................................................................... 4-48 4.3.10 Burrowing Owl .............................................................................................. 4-49 ALYSIS 4.3.10.1 Associated Covered Species and Special Management Species .......................................................................................... 4-49 4.3.10.2 Key Conservation Elements.......................................................... 4-49 4.3.10.3 Conservation Areas ....................................................................... 4-50 4.4 LANDSCAPE LEVEL CONSERVATION ANALYSIS .......................................... 4-50 4.4.1 Methods ......................................................................................................... 4-50 4.4.2 Results ........................................................................................................... 4-52 4.5 CONSERVATION TARGETS .................................................................................. 4-53 4.5.1 The Species-Area Relationship Model .......................................................... 4-53 4.5.2 Valley Floor Grassland and Vernal Pool Natural Community ...................... 4-55 4.0 CONSERVATION AN 4.5.2.1 Vernal Pool Ecosystems ............................................................... 4-55 4.5.2.2 Contra Costa Goldfields................................................................ 4-56 4.5.2.3 Valley Floor Grassland ................................................................. 4-58 4.5.3 Inner Coast Range .......................................................................................... 4-59 4.5.4 California Red-Legged Frog .......................................................................... 4-60 4.5.5 Callippe Silverspot Butterfly ......................................................................... 4-61 4.5.6 Riparian, Stream, and Freshwater Marsh ....................................................... 4-62 4.5.7 Giant Garter Snake ........................................................................................ 4-63 4.5.8 Coastal Marsh ................................................................................................ 4-64 4.5.9 Swainson’s Hawk .......................................................................................... 4-64 4.5.10 Burrowing Owl .............................................................................................. 4-65 4.6 RESERVE DESIGN AND CONSERVATION APPROACH ................................... 4-65 4.6.1 Valley Floor Grassland and Vernal Pool Natural Community ...................... 4-66 4.6.2 Inner Coast Range .......................................................................................... 4-67 4.6.3 California Red-Legged Frog .......................................................................... 4-67 4.6.4 Callippe Silverspot Butterfly ......................................................................... 4-69 4.6.5 Riparian, Stream, and Freshwater Marsh ....................................................... 4-69 4.6.6 Giant Garter Snake ........................................................................................ 4-71 4.6.7 Coastal Marsh ................................................................................................ 4-71 4.6.8 Swainson’s Hawk .......................................................................................... 4-72 4.6.8.1 Potential Reserve Areas ................................................................ 4-72 4.6.8.2 Criteria for Establishment of Agricultural Reserves ..................... 4-73 4.6.8.3 Tree Planting Criteria.................................................................... 4-74 4.6.9 Burrowing Owl .............................................................................................. 4-75 FIGURES Figure 4-1: Overview of the Conservation Analysis ..................................................................... 4-77 Figure 4-2: Key Corridors within the Plan Area ........................................................................... 4-79 Figure 4-3: Rarity Weighted Richness Map of Covered Species and Special Management Species within the Plan Area ........................................................................................... 4-81 Figure 4-4: Vernal Pool Disturbance Results, Barriers and Development.................................... 4-83 Figure 4-5: Contra Costa Goldfield Population Areas .................................................................. 4-85 Figure 4-6: California Tiger Salamander Known and Potential Range ........................................ 4-87 Figure 4-7: Distribution of Playa Pools and Vernal Pool Critical Habitat .................................... 4-89 Figure 4-8: Vernal Pool Conservation Areas ................................................................................ 4-91 Oct 2012 4-ii