Chapter 3
Chapter 4
Chapter 5
Chapter 6
Chapter 7
Chapter 8
Chapter 9
Chapter 10
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The RMG prepared a set of principles to guide the development of the habitat goals. In essence, the principles comprise the focus teams' and RMG's assumptions of what the goals should be. They were presented at the July 1997 public workshops and subsequently modified, based on input from the public, the focus teams, and the HAT. According to these principles, the goals should:
Project participants generally followed these guiding principles as they developed habitat recommendations. The RMG believes that the habitat vision and site-specific recommendations present a future view of the baylands that reflects the guiding principles.
The main objective of the Goals Project is to provide a vision of the types, amounts, and distribution of wetlands and related habitats needed to sustain a healthy baylands ecosystem. The vision described in this section presents a general array of habitats that should exist in the Bay well before the end of the next century. It attempts to address the competing habitat needs of the estuary's many species, especially those species that are dependent on tidal marsh and those that depend on salt ponds or diked seasonal wetlands, and it presents these goals graphically and in text. The vision comprises a mosaic of many kinds of habitats, and includes large areas of tidal marsh connected to provide movement corridors for small mammals and marsh-dependent birds; several large complexes of managed saline ponds for shorebirds and waterfowl; managed seasonal ponds and managed marsh in diked areas; continuous corridors of riparian vegetation along streams tributary to the Bay; and restored beaches and salt pannes. Undeveloped adjacent uplands buffer the baylands from disturbance. The vision embodies several ecological design considerations that are described in detail in Chapter 8. Key among these are that tidal marsh restoration should strive for large (2,000+ acres), connected patches of habitat; be centered where possible around existing populations of species of special concern (e.g., salt marsh harvest mouse and California clapper rail); and be emphasized along the Bay edge and at the mouths of streams to maximize benefits for fishes. Wherever possible, restored tidal marsh should also include natural features such as salt pannes, tidal ponds, and large tidal channels, which significantly increase the habitats' ability to support large numbers of many species of shorebirds and waterfowl. The loss of existing salt pond habitat due to restoration of tidal marsh should be offset by managing the remaining salt pond areas to maximize wildlife habitat values, particularly for shorebirds, waterfowl, and other water birds. The vision retains a number of "managed saline pond" complexes in the North Bay and in the South Bay, mostly located near important shorebird foraging areas. Each complex would be managed to maintain a range of salinities and water depths that favor the target bird species. In addition, some naturalistic, unmanaged salt ponds should be established. Where possible, a natural transition from mudflat through tidal marsh to upland should be established. Natural transitions also should occur between diked marshes and adjacent uplands. In all cases, upland buffers should be provided and managed to protect all wetlands habitats from disturbance. Restoring these natural transitions is important if we are to re-establish important baylands plant communities. Figure 7.1 shows the vision on maps. Recognizing that the habitats can be arrayed in more than one way, and reflecting some uncertainty regarding the optimal amounts and arrangements, this figure presents three views for each of the subregions except Central Bay, where the options for large-scale restoration are relatively limited. The kind of flexibility reflected by these views is also expected to be necessary in order to accommodate implementation constraints such as land availability or construction or maintenance costs. Additional alternatives could be shown that would favor the support of one species or group of species over another; for example, more tidal salt marsh would provide additional support for small mammals such as the salt marsh harvest mouse, at the expense of managed saline ponds for shorebirds and waterfowl, or vice versa. However, based on the current level of understanding, the general picture presented is expected to achieve the goal of sustaining healthy and diverse populations of fish and wildlife and strives to strike a balance between the needs of the various species.
The vision for the Suisun subregion includes extensive restoration of tidal marsh in both Suisun Marsh and on the Contra Costa shoreline. In Suisun Marsh there is a continuous band of restored tidal marsh from the confluence of Montezuma Slough and the Sacramento/San Joaquin rivers to the Marsh's western edge. This band of tidal marsh extends in an arc around the northern edge of the Marsh, and intergrades naturally with the adjacent grasslands to provide maximum diversity of the ecotonal plant communities. A broad band of tidal marsh also is restored along the southern edge of Suisun Marsh and around Honker Bay to improve fisheries habitat. On the majority of lands within Suisun Marsh, the long-standing practice of managing diked marsh primarily for waterfowl is continued, but these marshes are enhanced to increase their waterfowl carrying capacity. On the periphery of the Marsh, moist grasslands with vernal pools are enhanced, as is riparian vegetation along the streams. The vision for the Contra Costa shoreline includes restored full tidal action in many of the marshes that currently are diked or that receive muted tidal flow. Also, riparian vegetation is restored wherever possible. Figure 7.1 shows three ways that the vision for the Suisun subregion could be accomplished, including alternative ways to connect the restored tidal marshes on the west side of Suisun Marsh, and variations in the extent of restored tidal marshes along the south side of the Marsh. View 1 shows the westerly tidal marsh corridor placed between the railroad tracks and Suisun Slough, and includes a wide band of restored tidal marsh to the south of Roaring River. View 2 places the westerly tidal marsh corridor between Suisun and Montezuma sloughs, and shows a smaller area of restored tidal marsh south of Roaring River. View 3 locates the westerly tidal marsh corridor partially on the west side of the railroad tracks, with a minimum of tidal marsh south of Roaring River.
The vision for the North Bay subregion includes large areas of restored tidal marsh connected by wide bands of tidal marsh along the bayshore and extending well into the watersheds of the three major tributaries + Petaluma River, Sonoma Creek, and Napa River. Interspersed within the tidal marshes are several large areas of managed seasonal ponds a large complex of managed saline ponds. Riparian vegetation is re-established next to streams, and buffers are managed to protect all of these habitats. Figure 7.1 includes three views for this subregion that differ primarily in the arrangement of seasonal ponds and tidal marsh in the Sonoma Creek area. View 1 shows tidal marsh restored in a large patch on the east side of Sonoma Creek, with seasonal ponds on the surrounding lands. View 2 essentially reverses this pattern, with tidal marsh on the periphery and seasonal ponds in the center. View 3 demonstrates the possibility of introducing managed marsh in the upper reach of Sonoma Creek. A closer look at Views 1 and 2 in the North Bay reveals how the placement of the habitats in the landscape can change the overall ecological benefit of the restoration effort. Both views reflect roughly the same amounts of the various habitats, but View 1, with tidal marsh restored along Sonoma Creek, would likely provide greater benefit to fish. View 2, with tidal marsh restored around the periphery, would provide more opportunities for natural transition between tidal marsh and the uplands; this would increase benefits to plant communities and wildlife species that occur in this ecotonal habitat. Either view would provide similar values for the birds that would benefit from seasonal pond habitat.
The vision for the Central Bay has many areas of restored and enhanced tidal marsh, managed seasonal ponds, protected and enhanced beach dunes and islands, and restored natural salt ponds. The vision for this subregion is only shown in one view, View 1. No alternatives are shown because there are such limited restoration options.
The vision for the South Bay subregion includes several large areas of restored tidal marsh connected by wide corridors of similar habitat along the perimeter of the Bay. Several large complexes of managed saline ponds are located near mudflats and are interspersed throughout the subregion, and naturalistic, unmanaged salt ponds (facsimiles of historical ponds) are located on the San Leandro shoreline. Natural transitions occur from mudflat through tidal marsh and to adjacent uplands wherever possible. Adjacent moist grasslands, particularly those with vernal pools, are protected and managed for wildlife, and riparian vegetation and willow groves are restored along stream channels.
Figure 7.1 demonstrates three ways that the tidal marshes and managed saline ponds might be arrayed to achieve the vision for the South Bay. View 1 shows the saline ponds at the southernmost end of the Bay concentrated in two large complexes on either side of Guadalupe Slough, and a large pond complex on the north side of Mowry Slough. View 2 rearranges the ponds, placing more ponds east of Guadalupe Slough in the Alviso area, and shifting ponds from Mowry Slough to near Coyote Hills. Views 1 and 2 result in similar amounts of the various habitats being created, but they are simply arranged differently. View 3, however, shows the amount of managed saline ponds increased by about fifty percent, and a resulting decrease in the area of restored tidal marsh. As explained in the next section, these views reflect the upper and lower limits of acreage recommendations made by the Project participants. As with the views in the other subregions, there likely are other ways to arrange these habitats and still comply with the Project's ecological design considerations.
The vision is the "big picture," and represents what we would like to achieve for the benefit of the fish and wildlife of the baylands ecosystem. Project participants developed recommendations for actions that would help achieve the vision, all of which are based on one fundamental tenet: there should be no additional loss of wetlands habitats within the baylands. The following recommendations vary widely in specificity and scope, and they should be seen as a starting point for further discussion and evaluation. For the purposes of presenting the recommendations, the subregions are divided into several segments. These segments are identified alphabetically, beginning in Suisun Bay. Figure 7.2 shows the location of each segment. Habitat acreage goals for each of the subregions are presented on bar graphs. These goals are derived from the recommendations described below and from the design considerations described in Chapter 8. The various views shown in the bar graphs correspond to the views of the vision just presented. To put these acreage goals into perspective, the bar graphs are shown beside similar graphs of past and present habitat acreages. It is important to note that the graphs of habitat goals depict acreage ranges and do not represent the same level of certainty as do the graphs of the past and present habitat coverages.
The Suisun subregion consists of Segments A and B. The overall goal for this subregion is to restore tidal marsh on both sides of the Sacramento River and to restore and enhance managed marsh, riparian, grasslands, and other habitats. In Suisun Marsh (Segment A), the main areas of restoration are along the east side of Montezuma Slough, along the bay shore south of Roaring River, in the Nurse Slough area, on the north and west edge of Potrero Hills, and along a corridor from Potrero Hills to the west end of the Marsh at Morrow Island. On the Contra Costa shoreline (Segment B) recommendations focus on improving muted tidal areas. The approximate acreage goals for the key baylands habitats are shown with past and present acreages in Figure 7.3. As the graphs indicate, the three views in the vision result in considerably different amounts of habitats. In general, the goals for the entire Suisun subregion call for increasing the area of tidal marsh from the existing 9,000 acres to between 30,000 acres and 36,000 acres, while maintaining between 31,000 acres and 38,000 acres of managed marsh. Actions for achieving these goals are described below. The locations of these actions are indicated in Figure 7.4
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Segment A: Suisun MarshThe main objectives in Segment A are to restore tidal marsh in several large areas around the periphery of the Marsh and to enhance managed marsh for waterfowl and shorebirds. The peripheral tidal marshes should be connected by corridors and should transition naturally to adjacent uplands. Upland buffers should be provided where possible. Recommendations for Segment A include:
Segment B: Contra Costa ShorelineThe objectives for this segment are to enhance management of existing marshes and restore tidal marsh in several areas of existing muted tidal marsh. Also, existing buffers should be expanded. Recommendations for Segment B include:
The North Bay subregion consists of Segments C, D, E, and F. The overall goal for the North Bay is to restore large areas to tidal marsh, particularly along the perimeter of the Bay and adjacent to the Petaluma River, Sonoma Creek, and Napa River. Seasonal wetlands should be enhanced at several locations, especially in the Sonoma Creek area and on the Marin shoreline. Some of the inactive salt ponds should be managed as managed saline ponds to maximize their habitat values for shorebirds and waterfowl; others should be restored to tidal marsh. The goals also include protecting and enhancing tributary streams and riparian vegetation, protecting and improving upland buffers, restoring shallow subtidal habitats, and preserving and restoring eelgrass beds. The approximate acreage goals for the key baylands habitats in this subregion are shown with past and present acreage in Figure 7.5. As the graphs indicate, two of the future views result in similar amounts of habitats, while the third view changes the amounts somewhat to reflect the possibility of including managed marsh in the vision. In total, the goals for the North Bay subregion call for increasing the area of tidal marsh from the existing 16,000 acres to more than 37,000 acres, and creating between 8,000 acres and 12,000 acres of managed seasonal ponds. Actions for achieving these goals are described below. The locations of these actions are indicated in Figure 7.6 North Bay Subregion.
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Segment C: Carquinez Bridge to Tolay CreekThe main objectives in this segment are to restore tidal marsh in the Napa River and Sonoma Creek watersheds and ensure a continuous band of this habitat along the bayshore, to retain a large complex of managed saline ponds and enhance the management of seasonal ponds in other diked areas and, where possible, to enhance marsh/upland transitions and buffers. Recommendations for Segment C include:
Segment D: Petaluma River AreaThe main objectives in this segment are to restore a continuous wide band of tidal marsh along the bayfront, and to restore tidal marsh on both sides of the Petaluma River, particularly on the east side of the River, between Highway 37 and False Bay. Recommendations for Segment D include:
Segment E: Petaluma River to Point San PedroThe main objectives in this segment are to restore tidal marsh and create managed seasonal ponds. Tidal marsh should be restored in a wide, continuous band along the bayfront between Gallinas Creek and Black Point, ensuring a natural transition to uplands, where possible, and providing an upland buffer outside the baylands boundary to protect adjacent grasslands and oak woodlands. Managed seasonal ponds should be created in areas not restored to tidal marsh, and should include natural transitions to adjacent uplands. Tidal marsh also should be restored along Novato Creek, from the mouth upstream to Highway 101. Recommendations for Segment E include:
Segment F: Point San Pablo to Carquinez BridgeThe emphasis in this segment is to protect and enhance existing tidal marshes, beaches, and uplands, and to restore tidal marsh at two sites. Specific recommendations for Segment F include:
The Central Bay subregion consists of Segments G and H on the west side of the Bay, and Segments I and J on the east side of the Bay. Habitat goals for the Central Bay subregion generally call for protecting and enhancing all existing tidal marsh areas. They also include restoring tidal marsh habitats where possible (including dead-end sloughs), particularly at the mouths of streams; protecting and enhancing tributary streams and riparian habitats; protecting and improving upland buffers; restoring shallow subtidal habitats, and preserving and restoring eelgrass beds. Of particular importance in this subregion, especially in segments H and I, is the need to control peppergrass and smooth cordgrass as a part of tidal marsh restoration. The approximate acreage goals for the key baylands habitats in this subregion are shown with past and present acreage in Figure 7.7. Because topography and existing urban development limit the potential for large-scale habitat conversion, the goals only include recommendations for a few hundred acres of tidal marsh restoration. Actions to achieve these goals are described below, and the locations of these sites are indicated in Figure 7.8.
Segment G: Point San Pedro to Golden Gate BridgeThe objective in this segment is to restore and enhance many relatively small sites with a diversity of habitats. Specific recommendations for Segment G include:
Segment H: Golden Gate Bridge to Coyote PointThe objective in this segment is to restore sand dunes and tidal marsh at limited sites. Specific recommendations for Segment H include:
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Segment I: San Leandro Marina to Oakland Outer HarborThe objective in this segment is generally to protect, enhance, and restore various relatively small habitat areas, and eradicate smooth cordgrass throughout. Recommendations for Segment I include:
Segment J: Oakland Outer Harbor to Point San PabloThe objective in this segment is to restore, enhance, and protect a diversity of habitats. Recommendations for Segment J include:
The South Bay subregion consists of segments K through R, moving counterclockwise around the Bay. In this subregion, the goals primarily call for restoring large areas of tidal marsh and managing some salt pond complexes to ensure their habitat values for shorebirds and waterfowl habitat. Wherever possible, tidal marsh should intergrade naturally with the uplands, seasonal ponds should be enhanced, and riparian vegetation and willow groves should be restored. Of particular importance in this subregion, especially in segments P, Q, and R, is the need to control peppergrass and smooth cordgrass as a part of tidal marsh restoration. The approximate acreage goals for the key baylands habitats in this subregion are shown with past and present acreages in Figure 7.9. As the graphs indicate, two of the future views in the vision result in similar amounts of habitats, while the third reflects an increase in the amount of managed saline pond habitat. In general, the goals for the South Bay subregion call for increasing the area of tidal marsh from about 9,000 acres to between 24,000 acres and 29,000 acres, and establishing between 10,000 acres and 15,000 acres of managed saline ponds. Actions to achieve these goals are described below, and the locations of these actions are indicated in Figure 7.10
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Segment K: Coyote Point to Steinberger SloughThe main objectives in this segment are to restore and enhance tidal and diked marsh areas, and to establish a large complex of managed saline ponds. Buffers should be provided for existing habitats. Recommendations for Segment K include:
Segment L: Steinberger Slough to Dumbarton BridgeThe main objectives in this segment are to restore tidal marsh throughout, providing a continuous band of marsh along the bayfront, and to establish a complex of managed saline ponds. Recommendations for Segment L include:
Segment M: Dumbarton Bridge to Alviso SloughThe main objectives for this segment are to restore a large area of tidal marsh between Guadalupe Slough and Alviso Slough, and to establish one or two large complexes of managed saline ponds. Restoration should emphasize providing a continuous band of tidal marsh habitat along the bayfront, providing more buffers, and improving management to reduce human impacts and predators. Recommen-dations for Segment M include:
Segment N: Alviso Slough to Albrae SloughThe main objective in this segment is to restore tidal marsh throughout most of the segment, providing a continuous corridor of tidal marsh along the bayfront, and to provide a large complex of managed saline ponds. The type of tidal marsh created (salt or brackish) will be dependent on the amount and proximity local freshwater outflows. Restoration should emphasize re-establishing a natural transition between tidal marsh and adjacent wetlands and upland habitats. Recommendations for Segment N include:
Segment O: Albrae Slough to Newark SloughThe main objective for this segment is to enlarge the Mowry, Calaveras/Dumbarton tidal marsh , and to establish a large complex of managed saline ponds. Recommendations for Segment O include:
Segment P: Newark Slough to Alameda Flood Control ChannelThe main objectives for this segment are to establish one large complex of managed saline ponds in the southern part of the segment, and to restore the remaining area to tidal marsh. Restoration should emphasize natural transition of tidal marsh to uplands at Coyote Hills, and a continuous corridor of tidal marsh around Dumbarton Point. Recommendations for Segment P include:
Segment Q: Alameda Flood Control Channel to Highway 92The objectives for this segment are to establish two large complexes of managed saline ponds and restore the remaining area to tidal marsh. Restoration should ensure a continuous corridor of tidal marsh along the bayshore. Recommendations for Segment Q include:
Segment R: Highway 92 to San Leandro MarinaThe focus within this segment is to investigate the potential to restore barrier beach and natural salt pannes, and to establish some managed saline ponds. Recommendations for Segment R include:
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The San Francisco Estuary Baylands Goals Site is housed at the San Francisco Estuary Institute.
The San Francisco Estuary Baylands Goals Site is mirrored at the California Environmental Resources Evaluation Center.
San Francisco Estuary Institute Website contact: todd@sfei.org.
San Franicisco Estuary Baylands Goals Website contact: zoltan@sfei.org.
This page was last built on Thu, Sep 3, 1998 at 7:57:04 AM.
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