Benthic Habitat Mapping with Advanced Technologies and Their Application
James V. Gardner and Larry A. Mayer
The ability of today’s scientists to map the seafloor was unheard of two decades ago. Navigational accuracies, as well as elevation and spatial resolutions, have now reached the decimeter scale. But are today’s resolutions fine enough for biologists trying to characterize specific benthic habitats? Do biologists know what resolutions are necessary to define their benthic habitat of interest? Once biologists have high-resolution data, do they have the technologies to visualize and analyze this newly acquired data? Do agencies have the budgets required to use 21st century technology? High-resolution seafloor mapping technologies come in a variety of flavors with a variety of resolutions, from airborne lidar to underwater photography. Each system has its own pros and cons relative to the particular goal of the seafloor mapper (see Figure 1). For instance, a living platform coral reef can be efficiently mapped with an airborne lidar, but the spatial resolution is 2 m × 2 m at best, with a depth resolution of a few centimeters. The data are spectacular, albeit costly. But are these resolutions good enough to characterize the platform coral reef habitat for biological or management purposes? If not, then maybe underwater video and/or still photography is required. It is very labor intensive to acquire and process underwater video and/or still photography into useful imagery. Although the spatial resolution can be mm scale, there is poor vertical resolution unless stereo photography is collected.