Volume 52

Mapping Bentbic Habitats Using Side Scan Sonar


Authors
Appeldoorn, R.S.; Rivera, J.A.; Prada, M.C.
Download PDF Open PDF in Browser

Other Information


Date: November, 1999


Pages: 402-414


Event: Proceedings of the Fifty Second Annual Gulf and Caribbean Fisheries Institute


City: Key West, Florida


Country: USA

Abstract

Detailed, but large scale habitat mapping is necessary if fisheries researchers are to investigate habitat-species distributions on spatial scales relevant to fisheries management and marine conservation, and identify essential fish habitats and the qualities that underlie their importance. The latter will include both the immediate structural qualities of a given area and the liokages among surrounding habitats. Knowledge of the underlying structure of habitat function should allow simple roles to be developed for future identification and protection of critical habitats. Despite over 40 years of concentrated academic investigation in the area of La Parguera, Puerto Rico, including geological mapping, there is no comprehensive habitat map suitable for large-scale biological studies. Developing such a map is now feasible using remote sensing and geographic information system (GIS). We are using side sean sonar (SSS) to develop a habitat map extending from the shoreline to the edge of the insular platform and covering over 20 nautical miles square (nm2). SSS is advantageous over airbome remote sensing in its greater depth range and greater resolution. The SSS associated navigation equipment (computer, software, DGPS) and electric winch are mounted on a 22-ft vessel. A 300 kHz transducer is lowed over l00-m wide paths to collect bottom images. To create larger views, georeferenced mosaics are generated from individual images using GIS technology. To date we bave identified broad areas of habitat and located unknown patch reefs in otherwise soft-sediment areas. At 300 kHz, metal-frame fish traps were not detected, although evidence of their effect on corals were. Although SSS technology is valuable, its success requires proper logistical set-up, plus expertise in computers and electronics.

PDF Preview