Benthic Habitats of the Florida Keys derived from color aerial photography collected between 1991-12 and March 1992 (NCEI Accession 0143928)

This project was a cooperative effort between the National Ocean Service and the Florida Department of Environmental Protection's Florida Marine Research Institute (now called the Fish and Wildlife Research Institute). The goal of the effort was to produce shallow-water (from 0 to approximately 30 m water depth) benthic habitat maps of the Florida Keys and adjacent waters.

The maps were generated by expert visual interpretation of 1:48,000 scale color aerial photography and subsequent photogrammetric, stereo, digital compilation of interpreted habitat polygon boundaries from aerial photography. The Minimum mapping unit = 0.4 hectare (4,047 sq m; 1 acre) for all habitat. Patch reefs may be <0.5 ha. The aerial photography was acquired using a NOAA jet from December 1991 through March 1992. The photography was acquired with 60% side and 80% forward overlap to facilitate stereo compilation. Approximately 450 aerial photographs were acquired and used for the mapping project. Ground validation of interpreted habitat polygons was performed by visual verification at actual field sites prior to compilation. Aircraft Inertial Measurement Unit data were used to correct photography positioning in photogrammetric analytical plotters. The analytical solution used in the photogrammetric plotter for positioning was applied to bundles of 30-40 adjacent, overlapping aerial photographs. The stereo positioning of the photography was < 1 m. Digital data for bundles of compiled aerial photographs from the photogrammetric stereo plotter was imported into the ESRI ArcInfo GIS. The GIS was used to merge and edit the vector and attribute features of the 15 bundles to generate a mosaic benthic habitat map of the Florida Keys and adjacent areas covered by the aerial photography. Field validation of digitized habitat features visible in the aerial photography mosaics was performed to ensure correct interpretation. An assessment of the correctness of the interpreted digital map was performed by experts familiar with the the seafloor habitat found in the Florida Keys.