Development of Regional Objectives for Southern California Coastal Wetlands using Landscape-level Metrics

Restore America’s Estuaries December 13, 2016

Jeremy Lowe, San Francisco Estuary Institute Upper Newport Southern California Bight

Point Conception County Line (Santa Barbara/Ventura) 1. Gaviota Coast

2. Ventura Coast Santa Monica Mountains

3. Santa Monica Bay Palos Verdes

4. San Pedro Bay San Onofre Mountains 1. Bight-wide objectives 2. Sub-regional objectives 3. Management recommendations 5. San Diego Coast

Tijuana Habitat Losses 100%

90% Marine 80%

70% Non-wetland 60%

50% Non-tidal wetland 40%

30% Different estuarine wetland

20%

10% No change

0% Bight Gaviota Ventura Santa San Pedro San Diego Coast Coast Monica Bay Bay Coast Structure of Objectives

Bolsa Chica • Total Estuarine Area • Habitat Distribution • System Coherence • Archetype Distribution • Wetland Size • Transition Zones • Physical and Hydrologic Processes Total Estuarine Area

Historical Present

Tijuana Total Estuarine Area

Present Future

Tijuana Expand overall estuarine area toward historical levels, constrained by development with 0.6m sea level rise. Total Estuarine Area

400 Future: SLR 0.6m 350

300

250

200 Tidal Marsh

Intertidal Flat Area (ha) Area 150 Subtidal 100

50

0 Historical Present Undeveloped Extent Total Estuarine Area Area = 8320 ha

Realize a total of 8300 ha by 27%, maintaining the existing 4200 ha and 2270 ha

restoring an additional 4100 ha. 54%, 4480 ha

19%, Subregion Restore 1570 ha Gaviota Coast 280 ha Ventura Coast 1660 ha Santa Monica Bay 170 ha San Pedro Bay 1160 ha San Diego Coast* 810 ha Bight 4100 ha Habitat Distribution

Ballona Santa Ana Approximate the historic distribution of habitat types and provide redundancy of habitat types across systems in the region. Habitat Distribution

Historically, estuarine wetlands were composed of 63% marsh, 29% flats and 8% subtidal in the Bight Region. Habitat distribution in the subregions should be made up of the following proportions:

Subregion % Tidal flats % Marsh Gaviota Coast 29% 50% Ventura Coast 22% 63% Santa Monica Bay 19% 71% San Pedro Bay 26% 69% San Diego Coast 35% 59% Mission Bay Bell Canyon Malibu

Bataquitos Lagoon Tijuana Realize distribution of archetypes comparable to historical conditions in their appropriate locations within the subregion. Archetype Distribution

Gaviota Coast Gaviota State Park Example - Maintain and enhance at least 10 small creeks in the subregion. Example - Maintain 6 lagoon or estuary systems in the Gaviota region. System Coherence

Historic Santa Ana River Mouth System Current fragments include Santa Ana River, Santa Ana River Wetlands and Talbert Marsh

Maintain coherence of existing systems. Reconnect currently fragmented systems and to their watersheds. Wetland Size

60

50

40

30

20

10

0 0-20 ha 20-50 ha 50-100 ha 100-200 ha 200-300 ha 300-400 ha 400-500 ha 500-750 ha 750-1000 ha 1000+ ha

Historic Present 2050 Undeveloped Constrained

Ensure adequate patch size distribution of systems Transition Zones

Elevation San Dieguito Public ownership San Dieguito Enhance connectivity with upland habitats and maintain existing transition areas. Physical and Hydrologic Processes • Support internal structure and habitats in other objectives. • Include structural elements that were present historically. • Objectives are related, and cannot be accomplished in isolation.

Upper Newport

1. Restore tidal prism and residence time 2. Reduce coastal jetties 3. Manage water and sediment inflow Summary of objectives

1. Total estuarine area is based on future projections. 2. Habitat distribution is based upon historical mapping. 3. Maintain archetype distribution in subregions. 4. Reconnect fragmented systems guided by historical archetype. 5. Increase system sizes generally. 6. Maintain existing and restore additional transition zones. 7. Maintain and enhance physical and biological processes. Carpinteria

Thank you