marilyn latta eden landing working group october 27, 2009 subtidal habitat update eden landing...
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Marilyn LattaEden Landing Working Group
October 27, 2009
Subtidal Habitat Update Eden Landing Living Shoreline Project Ideas
Historical Abundance
Commercial oyster farmsEden Landing
Dungeness crab fisherySalmon fleet
Bay shrimp fishery
Hunting and shellmounds
Hydrographic surveys
The Albatross surveys
Steelhead streams
Habitats in San Francisco Bay
• Tidal marsh ~40,000 acres• Tidal flats ~30,000 acres• Eelgrass beds ~3,000 acres• Native oyster and other shellfish beds (?)• Creeks – over 1,000 miles
• Shallow and deep subtidal ~250,000 acres
Photo credits: www.lorenz-avelar.com
Submerged Aquatic Vegetation
Artificial Structures
Shellfish Beds
Sandy shoals
Mud/silt/clay/shell mix
Pebble/cobble/gravel
Rocky Outcrops
Algal Beds
Photo credits: www.bluewaterimages.com
Oakland
Benicia
Richmond
San Rafael
San Francisco
September 2009
0 2.5
Miles
0 2.5
Kilometers
California Department of Fish & Game San Francisco Bay Bathymetry (Feet)
Eelgrass (Zostera marina) Restoration Sites1
Oyster Restoration Site
Documented Intertidal Oysters2
Creosote Pilings (DRAFT - for graphics only)
Road
Current Estimated Range of Subtidal Oyster Distribution
Eelgrass (Zostera marina) Habitat3
Agar (Gracilaria) Habitat4
1Boyer (unpub.)2Harris, 2004;Smithsonian/UC Davis; Attoe, 2008; traylor-Dutra; Grosholz, 2008; Caltrans, 2009.3Merkel, 2003, 2009.4NOAA, ORR, Environmental Sensitivity Index, 2006 .
0 - 33 - 1212 - 2020 - 30
30 - 4040 - 5555 - 6565 - 80
80 - 100100 - 150150 - 282
GIS Maps Being Produced
• Subtidal Habitat Types• Habitat Stressors• Informed Siting of Projects
Subtidal Habitat Conceptual ModelsWim Kimmerer
Functional Connections Across Habitats
Habitats and Function are Linked• Watershed: elevational gradient of sediments• Sloughs/channels: hydrology, food, larval transport• Offshore shoals: shallow water spawning/rearing• Estuary wide: Migratory and feeding routes
Species use multiple depths and vegetation types• invertebrates, crabs, shrimps, shellfish• herring, salmon, smelt, sturgeon, rays, sharks• shorebirds, diving ducks and waterfowl• marine mammals
Ecosystem-based Approach• arrays of natural habitat types• multiple objectives
Graphic: www.baynature.org
Transition Zones on Both Edges
Upland transition Subtidal transition
Wetland edges: sand bars, shell beds, kelp and eelgrass fringe, rocky intertidal
Increase Subtidal Design Integration
shoreline-tidal-submerged habitats
Design Integration1. Reduce habitat fragmentation, increase connectivity
2. Plan for more shallow water habitat and maximum edges
3. Design gradual slopes and a variety of topography
4. Pay attention to “subtidal transition zones”
5. Optimize natural sediments to promote self-maintenance
Artificial Structures6. Reduce and modify hard structures to protect habitat
Increase Subtidal Design Integration
shoreline-tidal-submerged habitats
Monitor existing native species7. Survey existing subtidal resources and species
use8. Enhance current habitat for aquatic species9. Restore offshore shellfish, eelgrass beds, fish
habitats
Manage invasive species10. Survey for Aquatic Invasive Species11. When feasible, eradicate invasives
Control marine debris12. Identify trash hot spots, prevent sources of
debris
Photograph at low tides13. Photomonitor sites at extreme low tides
Native Olympia Oysters:Ostrea conchaphila
Habitat Engineers:
• Range: Chile to Alaska
• Small: usually 1.5 - 2”, some to 3”
• Attach to shell, hard substrate, mud/cobble
• Planktonic larvae, settle in embayments
• Filter feeders, water quality
• Co-evolved with natives, key niche space
• Food source for other invertebrates, birds, fish
2007 Native Oyster Recruitment
Native Eelgrass:Zostera marina
Habitat Builders:
• sediment infauna (clams, worms, etc.)
• epibenthic invertebrates (sponges, etc.)
• fishes (pipefish, anchovy, etc.)
Traps sediments, reduces erosion
Breeding ground for Pacific herring
Foraging area for dungeness crabs, birds,
& marine mammals
Two Marin Restoration Sites: > 10,000 new shoots
Assessment ProjectsNative Eelgrass, Shellfish, and Creosote Pilings
Eelgrass and Shellfish: Ecosystem Engineers• niche space for invertebrates• fish forage and spawning• habitat for Dungeness crabs, salmon, diving ducks & marine mammals
Project Elements:• Key functions• Restoration methods• Bay-wide acreage goals• Priority areas for research
Creosote and Artificial Structures:• benefits and impacts of pilings• proposed action plan• potential removal, encapsulation
Living Shorelines: A soft bioengineering approach
Living Space: employ natural habitat elements to protect shorelines from erosion while also providing water quality benefits and critical habitat.
Living Shorelines: Issues for study in SF Bay• Scale: what acreage is needed to slow wave action?• Suitability: must be matched to site conditions• Permitting: fill considerations in the subtidal zone• Monitoring: functional connections between habitats• Pilot: test effectiveness thru experimental designs
Katharyn Boyer, SFSU
Robert Abbott, Environ
Proposed Eden Landing Project May 2010- May 2011:• Monitor existing populations
• Final Design and Permitting
Summer 2011:• Install two acre project
2011- 2013 Monitoring Tasks:Number of oysters recruited/year; number of adults persisting/yearNumber of eelgrass shoots propagated/year, persisting/year
Presence/absence and diversity of species use (epifauna, fish, birds) at the treatment sites and at control sites at each location
Measurement of change in sedimentation rates between subtidal treatments and marsh/riparian edge, at the treatment sites and at control sites
Measurement of change in flow velocity rates between subtidal treatments and marsh/riparian edge, at the treatment sites and at control sites
Marilyn Latta, Project ManagerSubtidal Habitat Goals ProjectState Coastal [email protected]
Thank You