| Supplemental information |
***UPDATES*** The data were revised on 01-26-10. This revision removed misclassified kelp at Ellwood Pier north of Santa Barbara. This data were revised on 09-29-09. The revisions resulted in the removal of polygon overlap which increased overall kelp area 0.51 sq. mi. The overlap involved the following administrative beds: (a) South coast bed 30 (0.000589 sq. mi.), bed 101 (0.000006 sq. mi.), bed 103 (0.000078 sq. mi.), bed 105 (0.000066 sq. mi.), bed 112 (0.000039 sq. mi.), bed 114 (0.000001 sq. mi.), bed 115 (0.000025 sq. mi.), bed 117 (0.000985 sq. mi.) (b) Central coast bed 207 (0.353178 sq. mi.), bed 208 (0.000029 sq. mi.), bed 210 (0.000014 sq. mi.), bed 211 (0.000070 sq. mi.), bed 212 (0.067350 sq. mi.), bed 214 (0.056737 sq. mi.), bed 217 (0.000008 sq. mi.) (c) North central coast bed 304 (0.000920 sq. mi.) and bed 305 (0.027513 sq. mi.) In addition, the data were intersected with the administrative kelp beds. *** The area from Orange County through San Diego County was not photographed, except for Pt. Loma Kelp, which was photographed. The remaining sections were photographed under contract by The Regional Nine Kelp Consortium. Other areas not surveyed due to cloud cover include: Franklin Point, San Mateo County to Terrace Point, Santa Cruz County; Point Pinos, Monterey County to Cypress Point, Monterey County; City of Cambria, San Luis Opispo County to Point Estero, San Luis Opispo County; Point Arguello, Santa Barbara County to Point Conception, Santa Barbara County. This image file was created from Digital Multi-Spectral Video image files. The original .IMG files created by the DMSV were converted to .FXD files to assure spectral resolution and integrity by a batchfix MS-DOS program. The images were then imported into TNTMips software and georeferenced using DOQs from the United States Geological Survey. After the images had been georeferenced they were re sampled to a 2 meter cell size using a nearest neighbor method designed by Microimages Inc. Areas with a high glint factor (reflection from the sun on choppy water) were extracted to enhance the classification process. All of the images were then mosaiced based on an affine feathering method. The images were subsequently feature mapped and automatically classified to display areas of kelp. The resampled and classified image was then exported into a Arcview TIF file. The TIF file was converted into and Arcview shapefile format for display purposes using a weed tolerance of 1.35. The Region Nine Kelp Consortium data was converted for JPEG to IMG file format, then imported into TNT Mips software and processed in the same manner as the above DMSV data. DISCLAIMER The user is cautioned against making direct comparisons between the various kelp surveys for the following reasons: 1) Timing of the survey is important, particularly with respect to growing season conditions in the ocean, and storms and harvest levels preceding the dates of survey photography. Seasonal variability may account for differences in surveys, which may not reflect a change in the bed's extent, productivity, or harvest level. 2) Statistical significance in change of area should be evaluated. To do this, a variance parameter is needed, which is obtained by repeated measurements. Most of the coastline, however, has been surveyed only on six occasions (1967, 1989, 1999, 2002, 2003, 2004, 2005). 3) Survey methods have not been/may not be consistent. Some method of calibration between the methods needs to be performed in order to insure a change of area is not due to survey instrumentation, and not misinterpreted as a biological change. 4) An area where apparently no kelp data are present may truly represent an area devoid of kelp, or may represent an area where kelp was not detected due to poor photo quality, missing photo coverage, or other issues with data collection and processing. Photo coverage is extensive for the state, but the user is advised to consult the photo index for each year to determine whether photographs were acquired for an area of interest.
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