Acres of Natural Communities Restored

The Measure

Restore large areas of natural communities for habitat connectivity and crucial ecological processes, along with supporting viable populations of native species.

Expectations
Increase acres of natural communities to contribute to suitable habitats for fish and other wildlife, restored habitat connectivity, and viable populations of native species
Performance Metrics

• Acres of natural communities restored
• This metric will be updated and evaluated every five years

Acres of Natural Communities Restored by Ecosystem Types

The bar graph displays habitat baseline data from the 2007 Vegetation Classification and Mapping Program dataset by ecosystem type in the Sacramento-San Joaquin Delta. The ecosystem types shown were condensed and categorized for visualization purposes. For a full description of the ecosystem types, please refer to the table under the Metric, Baseline, and Target section. The dark blue bars represent the baseline acreages, and the green bars represent the target acres needed by 2050 to improve ecosystem health. The red bars represent the 2016 total acreages per habitat type. These conditions are based on the 2016 Vegetation Classification and Mapping Program dataset.

The bar graph shows varied results in ecosystem types from 2016. Grassland areas, for example, were categorized as agricultural and urban areas. This is partly due to the timing of vegetation flyovers, which influenced how habitat was categorized. Some areas were used as grassland in the winter and as agricultural fields during the summer and fall. Differently, tidal wetlands and vernal pool complexes were overestimated due to error in GIS processing of up to 25%, exaggerating the baseline.

Restoration Project Numbers

Since 2016, many ecosystem restoration projects have been completed, restoring about 8,480 acres of additional habitat. The table below summarizes major habitat types in restoration projects between 2016-2022. During this timeframe, another 5,000 acres were in progress and 6,000 acres were being planned.

Next data update: Acres of natural communities will be calculated and evaluated from Delta and Suisun Marsh Vegetation Classification and Mapping updates. The next update for this visualization will be in 2024.

About the Measure

Historically, the Delta and Suisun Marsh supported more than 650,000 acres of natural communities including riparian, wetland, and oak savanna. However, more than 90 percent of those ecosystems have been lost through land conversion to agriculture and urban land uses. Reestablishment of some of these natural communities on the landscape will provide critical ecological functions such as aquatic primary production and vegetation community succession, as well as physical space, connectivity, and habitat structure that is important for native species recovery.

Planning and management efforts, such as recovery plans, species-specific resiliency strategies, and conservation strategies, identify specific actions for ecosystem preservation and restoration to meet species’ needs. At least 11 recovery and conservation plans exist that have geographic coverage in the Delta and Suisun Marsh. These plans identify restoration and management actions needed to achieve the recovery of 35 species of special-status plants and 86 fish and wildlife species of conservation concern (Appendix Q4, Delta Plan, 2022). Nearly half of these species of conservation concern are endemic to California.

Delta restoration targets are based on recovery and conservation plans and are organized by historical natural community types. Natural community types are classified by plant community structure and physical characteristics such as hydrology and landscape position. Restoration of complex ecosystems will require the reestablishment of native vegetation communities. Restoring a variety of native vegetation cover types will promote ecological resilience and native biodiversity. Large areas of natural communities will provide functional, diverse, and interconnected habitats suitable for fish and other wildlife and support the recovery of native species.

This performance measure tracks the acres of natural communities by ecosystem type restored in the Delta and Suisun Marsh.

Map Visualization of Baseline Ecosystem Habitat Types in the Delta.

Modern habitat community types in the Delta and Suisun Marsh are used for setting baselines for habitat acreages. Other habitat types such as managed wetlands and agricultural habitats are not being tracked for this performance measure.

Recovery and Conservation Plans Ecosystem Acreages

Targets for each natural community (ecosystem) type were derived from conservation and restoration targets identified in conservation and recovery plans within the Delta and Suisun Marsh (Delta Plan, Appendix Q4). Where conservation and recovery plans overlap, habitat acreages were combined into a single target.

Restoration targets from plans with geographically larger footprints are proportionally scaled for the Delta and Suisun Marsh regions. The table below lists the net increase of target acres by ecosystem type and associated the recovery and conservation plans within the Delta and Suisun Marsh used for setting the target acres of net increase by ecosystem type.

Ecosystem Type	Target Acres Net Increase	Source Reference (Recovery and Conservation Plans
Seasonal Wetland Wet Meadow Nontidal Wetland	19,000 acres	Central Valley Flood Protection Plan (DWR 2016b)
Willow Riparian Scrub/Shrub Valley Foothill Riparian Willow Thicket	16,300 acres	Central Valley Joint Venture Implementation Plan (Dybala et al. 2017b)
Tidal Wetland	32,500	Central Valley Flood Protection Plan (DWR 2016a, 2016b); Central Valley Flood Protection Plan (CVFPP 2017b); Giant Garter Snake Recovery Plan (USFWS 2017); Tidal Marsh Recovery Plan (USFWS 2013); Suisun Marsh Habitat Management Plan (USBR, USFWS, CDFW 2013)
Stabilized Interior Dune Vegetation	640 acres	A Delta Transformed (SFEI-ASC 2014)
Oak Woodland	13,000 acres	Central Valley Joint Venture Implementation Plan (DiGaudio et al. 2017b)
Grassland	No net loss	A Delta Transformed (SFEI-ASC 2014)
Vern Pool Complex	670 acres	Conservation Measure 9, Bay Delta Conservation Plan (DWR 2013)
Alkali Seasonal Wetland Complex	230 acres	Conservation Measure 9, Bay Delta Conservation Plan (DWR 2013)

Delta Plan Strategy and Recommendations

Each chapter of the Delta plan includes strategies to achieve the goals of the plan. These strategies are general guidance on achieving the objective laid out in the plan and in the Delta Reform Act of 2009. Associated with these strategies are recommendations. The recommendations describe more specific and implementable actions to support the achievement of Delta Plan strategies. Strategies and recommendations may also have associated performance measures. Delta Plan performance measures track progress in achieving desired outcomes for the Delta Plan. Below are the strategies and recommendations associated with this performance measure.

Strategy

Restore Ecosystem Function

Recommendations

ER RF. Delta Plan Interagency Implementation Committee Restoration Forum

Metric, Baseline, and Target

Metric

Acres of natural communities restored. This metric will be updated and evaluated every five years.

Baseline

Acres of natural communities from the 2007 Vegetation Classification and Mapping Program (VegCAMP) dataset by the California Department of Fish and Wildlife (CDFW), as designated below.

Ecosystem Type	Baseline Acres (2007 VegCAMP)
Seasonal Wetland Wet Meadow Nontidal Wetland	5,100
Willow Riparian Scrub/Shrub Valley Foothill Riparian Willow Thicket	14,200
Tidal Wetland	19,900
Stabilized Interior Dune Vegetation	20
Oak Woodland	0
Grassland	33,000
Vernal Pool Complex	5,100
Alkali Seasonal Wetland Complex	700

Target

Net increase of target acres of natural communities by 2050 are listed below.

Ecosystem Type	Target Acres Net Increase (From Baseline Acres)	Total Area (Baseline Acres Plus Net Increase)
Seasonal Wetland Wet Meadow Nontidal Wetland	19,000	24,100
Willow Riparian Scrub/Shrub Valley Foothill Riparian Willow Thicket	16,300	30,500
Tidal Wetland	32,500	52,400
Stabilized Interior Dune Vegetation	640	660
Oak Woodland	13,000	13,000
Grassland	No net loss	33,000
Vernal Pool Complex	670	5,770
Alkali Seasonal Wetland Complex	230	930

Interim Performance Assessment

To provide a short-term assessment of progress toward the restoration targets, intermediate milestones are evaluated every decade toward the 2050 target date. Assessments of the performance measure will consider the existing state of restoration in the Delta and disclose conditions impacting the rate of restoration interim progress.

Ecosystem Type	Baseline	Target Area (Baseline Acres Plus Net Increase)
Ecosystem Type	Baseline	2030	2040	2050
Seasonal Wetland Wet Meadow Nontidal Wetland	5,100	11,400	17,700	24,100
Willow Riparian Scrub/Shrub Valley Foothill Riparian Willow Thicket	14,200	19,600	25,100	30,500
Tidal Wetland	19,900	30,800	41,600	52,400
Stabilized Interior Dune Vegetation	20	240	450	660
Oak Woodland	0	4,400	8,700	13,000
Grassland	33,000	33,000	33,000	33,000
Vernal Pool Complex	5,100	5,300	5,500	5,700
Alkali Seasonal Wetland Complex	700	780	860	930

Tools evaluating restoration effectiveness and natural community conditions will be considered in interpreting this performance measure. These may include Wetland Regional Monitoring Program (WRMP) and Habitat Development Curves for wetland and aquatic resources, Tidal Wetland Monitoring Framework for the Upper San Francisco Estuary for fisheries benefits, and project-specific long-term monitoring and operations plans.