This reference contains the imagery data used in the completion of the baseline vegetation inventory project for the NPS park unit. Orthophotos, raw imagery, and scanned aerial photos are common files held here.

Aerial photographs were already available for the FIIS and it was decided to use these rather than conduct a new photo acquisition project. The Army Corps of Engineers lent a set of color-infrared (CIR) imagery taken in July 1997. This photoset was scanned at a resolution of 600 dpi to be used as a reference for vegetation mapping work (Figure 3a). Because we were not able to maintain possession of the CIR photoset, we obtained print copies of an additional photoset for use in the FIIS project. This set of photos was obtained from Aerographics, Inc1 – the same vendor who supplied the CIR photoset to the Army Corps of Engineers. This set was captured in true-color in April of 1997 for Fire Island, and in 1996 for the islands in the Great South Bay and the William Floyd Estate at a scale of 1:1,200. Two copies of each photo were acquired. One was sent to the FIIS headquarters in Patchogue and the other was kept at CMI. The true-color photographs were used to delineate and interpret vegetation polygons at Fire Island. Aerographics scanned a subset of these same photographs at 600 dpi to serve as a backdrop for head-up digitizing (Figure 3b). Only about half of the photoset was scanned, as there was considerable overlap area within the photos. These photos were georeferenced by collecting 10-20 control points from available USGS digital orthoquarterquads (DOQQs) for the area. Photos were georeferenced to a spatial accuracy of 5 m on the ground, determined from the root mean square error term provided by the software during georeferencing.