Mapping and Characterization of Nearshore Benthic Habitats around Vieques Island, Puerto Rico

The Vieques Island Mapping Project was initiated in September 1995 as a
cooperative effort between NSRR and the Sirenia Project (Military
Interdepartmental Purchase Request no. NOO38995MP00012). Caribbean Fisheries
Consultants, Inc. was contracted by the Sirenia Project to help produce the
desired information in conjunction with Sirenia Project biologists. Products
include maps delineating Vieques' benthic habitat and coastal wetlands, an
electronic georeferenced habitat map (UTM coordinate system) in a format
compatible with ARC/INFO (Environmental Systems Research Institute, Inc.) and
a report describing methods used, the classification scheme, and the
relationship of these habitats to manatee use of Vieques Island. These map
products complement the Navy's Vieques Land Use Management Plan by identifying
marine resources targeted for protection in the plan.

Objectives include producing maps of the coastal seagrass beds and other bottom
habitat (including coral reefs) surrounding the island of Vieques and
characterizing the species composition and density of seagrasses in areas
frequented by manatees near Vieques.

Ground truthing by boat around Vieques Island was conducted from May 14 to May
19 1996 and from October 4 through October 9 1996. The ground truthing was
conducted to verify the interpretation of benthic habitat visible in the
images, verify accuracy of the shoreline limits, and refine the habitat
classification scheme used for the Vieques maps. Three hundred and thirty-two
ground truth stations were established around Vieques Island, located on the
aerial image overlays, and digitized. These sites are plotted as a layer on
the habitat map. The listing of ground truth sites includes site identifier,
latitude and longitude, community classification, depteh, dominant community
elements, less dominant elements, and other pertinent information. Latitude
and longitude were obtained for each station in the field using a Garmin 45 GPS
unit. Water depth for each station was determined from a Hummingbird LCR - 400
Video Fathometer with transom mounted transducer. Underwater Hi-8 video and 35
mm photography were used to document observations at selected sites.

The habitat classification scheme used is similar to that used by Kruer and
others in southern Forida seagrass beds and other benthic habitats in the
Florida Keys National Marine Sanctuary and Biscayne National Park. This scheme,
also used for benthic habitat mapping at NSRR in 1994/1995 (Kruer 1995), was
refined for the Vieques Island mapping project by adding the category "sand
bottom with rock". Also, mangroves were mapped in interior areas.

The information for this metadata was partially taken from the report
- Mapping and characterization of Nearshore Benthic Habitats around Vieques
Island, Puerto Rico.