California Department of Fish and Wildlife 20160525 raster digital data http://bios.wildlife.ca.gov ftp://ftp.wildlife.ca.gov/BDB/GIS/BIOS/Public_Datasets/1500_1599/ds1503.zip This is a 5m raster summary of the feature sources described in the supplemental information section of this metadata document. For footprints and descriptions of those source eelgrass surveys please refer to the original vector dataset ftp://ftp.wildlife.ca.gov/BDB/GIS/BIOS/Public_Datasets/1500_1599/ds1503.zipSeagrass habitats are among the most productive and biologically diverse ecosystems on the planet. The most common type of seagrass in California is Zostera, or eelgrass, which grows under water in estuaries and in shallow coastal bays of the ecoregion. It is a flowering plant, not an alga, and occurs in dense beds. It helps prevent erosion and maintain stability near shore by anchoring sediment with its spreading rhizomes and slowing water flow. Eelgrass beds provide foraging, breeding, or nursery areas for invertebrates, fish, and birds. This file aggregates data from several sources across multiple years; see supplemental info. Features shown here should not be considered a representation of condition for any given year. Features represent the maximum extent of eelgrass found across multiple surveys over multiple years. To show eelgrass distribution in California. 5/4/2016 Update of San Francisco Bay with data from Merkel & Associates (2014). This data should approximate previous data from ERMA, (see below) however, some topological differences were noted and previous features were replaced in favor of these records directly from Merkel and Associates. Features are aggregated with attributes dropped. See original source data for additional detail. Digital maps of the distribution of eelgrass throughout San Francisco Bay were created from interferometric side-scan survey data. Following completion of the surveys, sonar traces were downloaded and processed into rectified mosaic images in a GeoTiff format using Chesapeake Technologies, Inc. Sonar Wiz. Eelgrass was mapped by manually digitizing from registered sidescan mosaics and aerial photographs using ESRI ArcGIS software. Update of Estero Americano with data from Andrew Weltz, CDFW (2014). Bed areas in the Estero Americano were surveyed between June and September 2014 by CDFW staff using global positioning system (GPS) technology, observation, and field notes. Polygon features were digitized from the survey data with the aid of 2012 National Agriculture Imagery Program (NAIP) imagery. Update of Big River Estuary with data from Andrew Weltz, CDFW (2015). Bed areas in the Big River estuary were surveyed on 9/21/2015 by CDFW staff using global positioning system (GPS) technology, observations, and field notes. Polygon features were digitized from the survey data with the aid of 2012 NAIP imagery. Update of Albion River Estuary with data from Andrew Weltz, CDFW (2014, 2015). Bed areas in the Albion River estuary were initially surveyed on 10/3/2014 by CDFW staff using GPS, observations, and field notes, with a follow-up survey on 5/21/2015. Polygon features were digitized from the survey data with the aid of 2012 NAIP imagery. Update of Bodega Bay harbor and Drakes Estero with data from Ocean Imaging (2010). This vector dataset was developed for the Sea Grant MPA Baseline Program as part of the project “High Resolution Nearshore Substrate Mapping and Persistence with Multispectral Aerial Imagery” (#R/MPA17 09-015). The study region is the California North Central Coast (NCC). The imagery used for this habitat classification were collected by Ocean Imaging (OI) and Fugro EarthData. OI acquired this imagery on 03/26/2010 using the Digital Multispectral Camera (DMSC). Details on this system and the data processing are below in the Lineage section of this document. Fugro EarthData acquired the imagery used for this project between 09/22/2010 – 09/23/2010 and delivered fully georeferenced and orthorectified, 12-bit imagery with a spatial resolution of 0.30 meters to OI in 2011. Details on this system and the data processing are also below in the Lineage section of this document. Individual DMSC and ADS40 scenes were mosaicked into sections based on the USGS orthoquads for the California North Central Coast in order to generate the multispectral imagery required to produce the habitat classification thematic maps of the California North Central Coast’s intertidal region and kelp beds from Pigeon Point up to Point Arena, including select bays and river mouths designated as MPAs. 9/9/2014 Update of San Francisco Bay and southern California regions (including Channel Islands) with sources available from NOAA's Environmental Response Management Application (ERMA - https://www.erma.unh.edu). See source features for specific survey data. 7/29/2013 Update area of Tomales Bay based on data recieved by Andrew Weltz, California Department of Fish and Wildlife. Source metadata: Abstract: Bed extents were digitized based on 2010 aerial imagery and 2013 ground-truthing surveys. Description: Zostera marina bed extents were digitized from 2010 CDFW aerial imagery. Photographs were taken on 6/29/2010 on the incoming tide following a -0.5 ft. low at 08:25. Photographs were georeferenced 5/6-5/8/2013. This shapefile was created 5/8/2013 - 7/26/2013. Credits: Shapefile digitized by Andrew Weltz of CDFW's Aquaculture and Bay Management Project from aerial photographs taken by Ron VanBenthuysen of CDFW and georeferenced by Andrew Weltz. 11/15/2009 Updated areas around Humboldt Bay with data provided by John Mello, CDFG. Those data derived from year 2000 IR imagery. Metadata abastract below: The areal distribution of Humboldt Bay (Humboldt County) California eelgrass was examined from aerial photographs taken in 18 September 2000 and on-ground observations. In ArcView 3.2® Geographic Information Systems (GIS) software the polygon drawing tool was used to delineate the extent of eelgrass coverage in the bay (Shull and Bulthuis 2002). Polygons were converted to shape files using ArcView 3.2 to calculate the areal distribution of eelgrass in hectares. The photomosaic was used to calculate eelgrass distribution. The lower intertidal limits of eelgrass beds were delineated using Humboldt Bay channels verified by visual observation during minus tides. Tidal elevation delineates the upper intertidal perimeter of the eelgrass beds adjacent to the shore. The upper intertidal perimeter of eelgrass beds was confirmed by walking to these areas at low tide or using a small boat at high tide and recording positions of bed perimeters with a handheld GPS. The GPS positions were compared with the delineation of the beds from the 2000 photo-mosaic. Only large continuous beds were measured. Pools and depressions in mid to high intertidal mudflats containing eelgrass were not included in the survey nor were eelgrass patches in sloughs around the bay. Seventeen eelgrass beds were defined, but only nine were used in the study (Fig. 1). Four eelgrass beds were in North Bay (beds 1, 4, 5, 6,), two in Central Bay (beds 9, 10) and three in South Bay (beds 12, 13, 15). Deep-water channels define the entire perimeter of bed 5 and the lower tidal elevation of beds 1, 4, 6, 9, 10,12, 13, and 15. Sample sites were located outside of shellfish culture operations. Large continuous eelgrass beds in North and South bays and narrow fringing beds in Central Bay cover 1890 ha. 6/27/05 Loaded additional areas for Elkhorn Slough eelgrass beds defined by Eric VanDyke. No additional attributes or metadata provided. Transmittal posted here: Sherry Palacios/Dick Zimmerman seagrass shapefile (UTM zone 10, WGS84) collected from a boat using differential GPS on April 4, 2000. As needed -124.324909 -117.098008 40.898141 32.600408 None eelgrass, seagrass, zostera ISO 19115 Topic Categories environment oceans None California None None. California Department of Fish and Wildlife Paulo Serpa Research Analyst II (831) 649-7143 Paulo.Serpa@wildlife.ca.gov See supplemental info for regional differences in source data. Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.5.1.7333 Raster Grid Cell WGS 1984 Web Mercator Auxiliary Sphere PROJCS["WGS_1984_Web_Mercator_Auxiliary_Sphere",GEOGCS["GCS_WGS_1984",DATUM["D_WGS_1984",SPHEROID["WGS_1984",6378137.0,298.257223563]],PRIMEM["Greenwich",0.0],UNIT["Degree",0.0174532925199433]],PROJECTION["Mercator_Auxiliary_Sphere"],PARAMETER["False_Easting",0.0],PARAMETER["False_Northing",0.0],PARAMETER["Central_Meridian",0.0],PARAMETER["Standard_Parallel_1",0.0],PARAMETER["Auxiliary_Sphere_Type",0.0],UNIT["Meter",1.0],AUTHORITY["EPSG",3857]] coordinate pair 0.000000006714873101998366 0.000000006714873101998366 meter D WGS 1984 WGS 1984 6378137.0 298.257223563 VAT_ds1503 OBJECTID Internal feature number. Esri Sequential unique whole numbers that are automatically generated. VALUE Year of source data. Features in this layer SHOULD NOT be considered a representation of condition for any given year COUNT_ 20180314 California Department of Fish and Wildlife Paulo Serpa Research Analyst II (831) 649-7143 Paulo.Serpa@wildlife.ca.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time