Humboldt Bay, California Benthic Habitats 2009

Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the Office for Coastal Management began collaborating with the California SeaGrant program and other local partners to support an ecosystem-based management (EBM) project for Humboldt Bay. One element of this project was to develop subtidal habitat goals for the long-term management of the bay and provide a framework for conservation and management across the land-sea interface. The imagery collection and benthic habitat delineation for Humboldt Bay were essential to the development of subtidal goals and implementation of EBM for the region. Together, these efforts will provide important and replicable data and an information framework for ecosystem-based coastal and marine conservation planning and implementation. 12 Bit 4 Band imagery was collected in June,2009 within 1 hour of either side of a minus one (-1) foot tide with low turbidity,low wind,low sun angle and no cloud cover. The horizontal spatial accuracy of the imagery is within +/- 3 meters CE95 of position on the ground and was captured at a spatial resolution (pixel size) of 0.54m x 0.54m. The imagery was tiled and named according to the existing USGS digital ortho quarter quad boundaries (ex. Arcata_South_NE.tif). A small buffer (~100 m) was produced with each tile to prevent gaps in coverage. Habitat features were interpreted and digitized on screen in an ARCGIS Geodatabase 9.3 resulting in accurate and efficient 3D extraction of the data. Habitats were delineated with a high level of detail with the minimum mapping unit (MMU) being 0.01 hectares(approx.10m x 10m).