A simple in situ labelling approach and adequate tools for photo and video quadrats used in underwater ecological studies

Ecological studies use quadrats to gather qualitative (1/0) and quantitative (density and surface coverage) information in terrestrial and marine sciences. Depending on the spatiotemporal scale of the assessment, this could be a pilot or a monitoring survey. For monitoring surveys, it is necessary to develop a code for the quadrat itself (in situ labelling), for the digital file (ex situ codification), and ideally, for both. The design of the quadrat used for these studies must accomplish ergonomics through certain specifications such as: made of highly resistant material; negative-buoyant but lightweight; anticorrosive (specially for marine environments); able to stay positioned on seafloor habitat; and compatible with the in situ labelling technique. The present paper is a comparison of quadrats of different materials and widths, including the implementation of an in situ and ex situ codification technique. Recommendations are made after several test hours sampling with quadrats.