terms of habitat acreage in the project area, the footprint of rack culture is about 1% of the eelgrass acreage. It was in this context that the committee considered whether the direct scale of impact on Drakes Estero resources was reflected in potential adverse changes to the structure and function of the Drakes Estero ecosystem as a whole (indirect impacts). In so doing, the committee understands that the acreage for bag and rack culture, and associated motorboats and human activity, move from place to place within permitted areas as the DBOC attempts to optimize production. Consequently, the spatial footprints integrated over time are larger than the footprint at any given time.

TABLE 2.1. Spatial extent of Point Reyes National Seashore and the Drakes Estero ecosystem with acreage designated for DBOC’s operations (all acreages came from the DEIS, except for wilderness and potential wilderness10). DBOC’s operations take place on uplands near the head of Schooner Bay and in tidal wetlands and subtidal waters of Drakes Estero. In addition to rack and bottom bag cultures, floating bags are also deployed; these are predominantly located in intertidal culture beds.

The Seashore and Drakes Estero Acres
Point Reyes National Seashore (including the Northern District of the Golden Gate National Recreation Area) 94,000
Wilderness 27,122
Potential wilderness 6,251
Potential wilderness, Drakes Estero (inter- and subtidal only) 1,363
Drakes Estero (Drakes Estero, includes Estero de Limantour) 2,500
Drakes Estero Project (focus of the EIS) 1,700
Drakes Estero Watershed 19,840
Drakes Estero intertidal (mud, sand flats including Limantour) 1,152
Drakes Estero eelgrass beds within the project area 737
DBOC Current A B C D
Special Use Permit (SUP) offshore 1,050 0 1,078.0 897.0 1,082.0
Upland DBOC facilities 4.6 0 4.3 4.3 4.3
Total acreage available for cultivation (intertidal + subtidal beds) 142.0 0 138.0 138.0 138.0
Culture beds for bottom bag culture (intertidal) 88.0 0 84.0 84.0 84.0
Culture beds for rack culture (subtidal) 54.0 0 54.0 54.0 54.0
Propeller scars in eelgrass beds11 ~50.0 0 ~50.0 ~50.0 ~>50.0
Area within which motorboat use occurs12 740 0 740 740 740


10 FR Doc.99-29779, available at: www.nps.gov/pore/parkmgmt/upload/lawsandpolicies_fr_doc_99_29779.pdf.

11 The 50 acres corresponds to polygons within which propeller scars are found (NRC, 2009).

12 These values assume that motorboat usage will stay roughly the same under the three action alternatives as assessed by the NPS for boat activity in 2010 (used for “current” in the table). However, this area could change for the action alternatives under which DBOC would follow an NPS-approved vessel transit plan.

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