Remote Sensing Oyster Reef Project

Oyster Reef Mapping

Traditional methods for monitoring subtidal oyster reefs rely upon extractive sampling techniques such as dredges, tongs, or quadrat sampling by divers. Remote sensing methods such as acoustic sounders and underwater video have the potential to greatly enhance the amount of detailed spatial information that can be obtained compared to traditional approaches. This project will compare acoustics (single beam, multibeam, and sidescan sonar), video, and quadrat sampling for characterizing the size and structure of three reefs, with the long-term aim being development of a general monitoring protocol. A report (see Grizzle et al. 2005 in RECENT PUBLICATIONS) will be available describing preliminary studies that led to this project. Ray Grizzle, Semme Dijkstra, and Brian Smith are the principal investigators. (Funded by NH Sea Grant; 2004-2006.)

Great Bay

Oyster reefs at Adams Point and Nannie Island that were preliminarily mapped using acoustics and underwater video


Great Bay Views

A comparison of outputs from video and acoustics mapping approaches. A (top): Photomontage produced from stills extracted from stationary video of Adams Point reef. A (bottom): Classification analysis of single beam sounder data showing six classes of bottom types for Adams Point reef, with grid used for video imaging. B (top): Photomontage for Nannie Island reef. B (bottom): Sidescan sonar image clearly showing shape of Nannie Island reef, with overlying grid used for video imaging