South Bay Salt Pond Restoration-- The Chance of a Lifetime!

Topics Covered in this Talk• Charge of the Science Team

• What is Restoration?

• Past and Current Habitats

• Major Ecological Communities

• The Science Strategy

• Some Key Questions

• Developing Our Knowledge Base

Charge of the Science Team

• Provide scientific direction for restoration planning, implementation and monitoring

• Bring science into all phases of the process and to all involved parties

• Develop a science strategy and conceptual models to guide the restoration of South Bay ecosystems

• Identify critical data needs

• Identify uncertainties

• Help guide consultant activities and review products

Having a Science Team…

• Is unique and proactive.

• Will help to assure that science is included at every phase of the project.

• Is essential for a successful program.

Interdisciplinary Practice of Environmental Restoration

Jackson, et al. (1995):

Ecological restoration is the process of repairing damage caused by humans to the diversity and dynamics of indigenous ecosystems.

• Science

• Technology

• Regulation/Policy

• Economics

• Public Interaction

Restoration as Project and as Experiment

Planning = Hypothesis

Implementation = Run the experiment

Monitoring = Collect/analyze data

Adaptive Management

• Using data collected during monitoring to improve restoration projects

• Apply to the current project to better achieve restoration goals

• Use to improve the design of future projects

Restore to What? What is the Goal?

• Native, indigenous ecosystem as a goal

• Improving ecological functioning as a goal

• Historical view helps guide restoration goals

• Current conditions guide restoration goals

San Francisco

BayHabitats ca. 1800

(SFEI EcoAtlas Project)

Our Urbanized Estuary

• Oakland Harbor • Carquinez Straights

Conversion to Salt Ponds

South Bay: Then and Now

0

10

20

30

40

50

60

70

80

90A

crea

ge (x

1000

)

Other 0 3

Bay Fill 0 13

Agriculture 0 1

Diked Wetland 0 7

Salt Pond 1 30

Tidal Marsh 57 7

Tidal Flat 21 14

Past Present

What are Tidal Salt Marshes?

• Inundated by tides twice a day

• Have water-logged, anaerobic soils

• Dominated by wetland, halophilic plant species:– Cordgrass (Spartina foliosa)

– Pickleweed (Salicornia virginica)

Cordgrass and Pickleweed

Mature Plant Community Zonation

• Low marsh: cordgrass

• Mid-marsh: pickleweed

• High marsh: saltgrass (Distichlis spicata), alkali heath (Frankenia salina), Gumplant (Grindellia humilis)

• Upland transition: saltgrass, alkali heath, coyote bush (Baccharis pilularis), Atriplex spp.

Tidal Marsh Zonation

low marshSpartina foliosa

mid-marsh plainSalicornia virginica

high marsh - upland transitionSalicornia virginicaFrankenia salinaDistichlis spicata

regularly inundated

high accretion rates

rarely inundated

low accretion rates

Ecological Succession: Ecosystem Development

• A salt marsh is formed when an area goes from a disturbed or former salt marsh site from to the mature community

• Natural restoration is called ecological succession—the process we want to mimic

• Salt marsh successional phases:– Open water

– Mudflat

– Vegetated mudflat

Tidal Salt Marsh Restoration Begins with Open Water…

… and the tides bringing in sediment, organisms and seeds.

 

Next, Mudflats form…

…stabilizing at an equilibrium point.

Then, Vegetation Colonizes

But, This is Not the End of the Process.As the marsh matures…

• Nutrients build up

• Species composition changes

• A mosaic of habitat types develops

Marsh Restoration Takes Time

• Time to reach marsh plain ~5-20 yrs

• Time for dominant plants ~10-35 yrs

• Maximum nutrient loads and full ecosystem functioning ~50-100 yrs

This Program will Take Time

• Projects will be implemented in phases– Collect data on progress– Apply to next phases– Collect funding for phases

• Natural processes take time

Salt Ponds as a Major South Bay Wetland Habitat

• Historically, existed in low acreage

• Extensively developed from late 1800s to 1940s

• Are wetland habitats with their own ecology

Those Crazy Salt Pond Colors

What causes those colors?

It’s the microorganisms! • Low to mid-salinity: Green algae dominate • Salinities increase: The algae, Dunaliella,

lends a lighter green color• Mid- to High Salinity: Dunaliella produces

a red pigment• Very High Salinities: Brine shrimp (Artemia

franciscana) provide orange colors andStichococcus (a bacteria) adds red hues

Many species use these ponds

Avian Biodiversity and Abundance

• 34 shorebird species—1 million birds

• 35 waterfowl species—250,000 birds

• At least 36 species of “other birds” closely associated with San Francisco Bay habitats

• At least 9 state- and federally-listed threatened or endangered species

Bird Species: Continental Population

Trends

• In General: Wetland-dependent bird populations are far below historic levels.

• Shorebirds: 16 of 47 U.S. species declined over the last 25 years

• Waterfowl: Steep declines in some species, such as pintail and canvasbacks

0

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20

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40

50

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70

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90

Acre

s (x

1000

)

Other 0 3 3

Bay Fill 0 13 13

Agriculture 0 1 0

Diked Wetland 0 7 4

Salt Pond 1 30 10

Tidal Marsh 57 7 31

Tidal Flat 21 14 14

Past Present Future

A Mix of Habitats…

…for a Diversity of Species

One thing is clear…we cannot go back to the 1800s

• Must consider importance of habitat changes– Salt ponds provide habitat– Urban conversion is difficult to reverse

• Must consider existing adjacent land uses– Impacts on the restoration (pollutant runoff)– Restoration impacts on the adjacent land (flood

prevention)

What is a Science Strategy?

• Provides a scientific framework– Conceptual Models—landscape and pond-

level– Key Questions and Data Needs– Modeling Needs

• Provides scientific input at all stages of the planning process

Why is this project so complex?

• Adjacent land uses

• Flood protection

• Agency requirements

• Pond subsidence

• Water quality

• Species diversity protection

• Sedimentation rates and patterns

Some Key Questions

• To what extent is the suspended sediment supply adequate for restoration?

• Can we prevent non-native, invasive species from dominating restored marshes?

• To what extent might restoration activities release contaminants? What are the ecological effects of released contaminants?

• What effects will South Bay restoration have on large-scale ecological features and processes?

More Key Questions

• How will the conversion of salt ponds to salt ponds and other

habitats affect shorebird and waterfowl numbers?

• Can remaining ponds be managed to increase their shorebird and waterfowl carrying capacity?

• What are the predictions for sea-level rise and how will that affect restored South Bay marshes?

Developing a Common Base of Understanding

• Science Team and other experts meet with Work Groups to share ideas

• Opportunities for public involvement in research, monitoring and data collection

• Stakeholders give input to the Science Team

How might this project effect you?

• Flood protection is a central goal

• Public access is also a project issue

• Changes in species communities

• Healthier South Bay ecosystem

• Improved water quality

Next Science Team Presentation:

• Restoration Constraints

• Scientific Uncertainties

• Complicating Factors