Tubbs Island Marsh Enhancement

Status Completed County Sonoma
Project Type Non-mitigation Location 38.12493° N, -122.43260° W Map
Project Area (Acres) 65.00 Last Updated 15 June 2018
Project Abstract This project has enhanced 65 acres of tidal marsh, sub-tidal, and marsh-upland transition environments on the San Pablo Bay National Wildlife Refuge. Goals are to support the re-establishment of native vegetation, improve estuarine-dependent wildlife habitats, and reduce or eliminate future mosquito population management issue.

Project Identification

CN8-98 BCDC - Record Number
592 JV - Record Number
235190 USACE - File Number

Habitat Plan

ActivityHabitatSubHabitatAcresActivity StatusWater Regime
Enhancement Unknown/unspecified habitat None 65.00 Completed

Related Habitat Impacts

HabitatAcres LostType of Loss
No Data


Tubbs Island Marsh Enhancement Completed 65.00


DateTypeDescriptionSite Name
2014-12-31 Project end date
2006-03-01 Project start date
2002-03-08 Groundwork end From WT:On-the-ground work completed
1999-04-12 Permit USACE permit issued
1999-01-05 Permit BCDC record number issued


Contact Andrea Jones Audubon California Not applicable/Unknown
Contact Julia Kelly Audubon California San Francisco Bay Program, Audubon California


Funding Need: $37,692

Enhancement Conoco-Phillips Company $200,000
Enhancement San Francisco Foundation Bay Fund (historic funding program) $88,000
Enhancement USFWS Challenge Cost Share $36,000
Enhancement USFWS Coastal Program at San Francisco Bay $15,000

Related CRAM Assessments

Visit DateVersionSite NameWetland TypeIndex Score
No Data

Performance Criteria

StatusDetailsEvaluation Date
Unknown/Unspecified See supplemental sheets taken from "Tubbs Island Restoration Plan & Environmental Assessment" dated August 1998 and prepared by the San Pablo Bay NWR. 2001-01-01
Upload files or links

No files found.

How to Use the Habitat Development Curve

Habitat Development Curves (HDCs) are used to determine the developmental status and trajectory of on-the-ground projects to create, restore, or enhance California wetland and stream habitats. Each HDC is based on assessments of habitat condition for different age areas of one habitat type that in aggregate represent the full spectrum of habitat development. The assessments of condition are provided by expert applications of the California Rapid Assessment Method (CRAM). Visit the CRAM website for more information about CRAM.

For each HDC, reference condition is represented by areas of a habitat that consistently get very high CRAM scores, have not been subject to disruptive management practices, and exist within landscapes that are protected and managed for their natural conditions. The horizontal lines intersecting the top of an HDC represent the mean CRAM score and standard deviation of scores for 25 qualifying reference areas.

The age of a project is estimated as the elapsed time in years between the groundwork end date for the project and the date of the CRAM assessment. To add or update a groundwork end date, use the Project Events form in Project Tracker (ptrack.ecoatlas.org). The minimum age in years of a non-project area, including any natural reference area, is estimated from all available local information, including historical maps and imagery, historical written accounts, and place-specific scientific studies of habitat development.

An HDC can be used to address the following questions:

  1. At what time in the future will the area of assessed habitat achieve the reference condition or other milestones in habitat development? The HDC can answer this question if the CRAM score for the assessed area is within the confidence interval of the HDC. The answer is the time in years along the HDC between the current age of the assessed area and the future date corresponding to the intersection of the HDC and the reference condition or other milestone.
  2. Is the area of assessed habitat likely to develop faster, slower, or at the same pace as most other areas of the same habitat type? The habitat area is likely to develop faster, slower, or at the same pace if the CRAM score for the area is above, below, or within the confidence interval of the HDC, respectively.
  3. What can be done to improve the condition of the habitat area or to increase its rate of development? HDCs by themselves cannot answer this question. Possible answers can be inferred by the following analysis that involves HDCs:
    1. Examine the HDC for each of the four CRAM Attributes;
    2. Identify the Attribute(s) scoring below the HDC;
    3. For any low-scoring Attribute, examine the component Metric Scores (note: the Metric Scores for any public CRAM assessment in the CRAM database can be obtained through EcoAtlas);
    4. Assume the low score of an Attribute is due to its low-scoring Metric(s);
    5. Consider modifying the design or management of the habitat area in ways that will sustainably increase its score(s) for the low-scoring Metric(s).

For more information about CRAM Attributes and Metrics, including their scientific rationale, see the CRAM Manual.

Display Habitat Development Curves For Wetland Type:

CRAM Site Scores