Biological data extraction from imagery – How far can we go? A case study from the Mid-Atlantic Ridge

In the past few decades, hydrothermal vent research has progressed immensely, resulting in higher-quality samples and long-term studies. With time, scientists are becoming more aware of the impacts of sampling on the faunal communities and are looking for less invasive ways to investigate the vent ecosystems. In this perspective, imagery analysis plays a very important role. With this study, we test which factors can be quantitatively and accurately assessed based on imagery, through comparison with faunal sampling. Twelve instrumented chains were deployed on the Atlantic Eiffel Tower hydrothermal edifice and the corresponding study sites were subsequently sampled. Discrete, quantitative samples were compared to the imagery recorded during the experiment. An observer-effect was tested, by comparing imagery data gathered by different scientists. Most factors based on image analyses concerning Bathymodiolus azoricus mussels were shown to be valid representations of the corresponding samples. Additional ecological assets, based exclusively on imagery, were included.

► Comparison between imagery analyses and corresponding discrete samples at a hydrothermal vent.
► Most factors based on image analyses of the dominant mytilid species were shown to be valid representations of the reality.
► Differences in faunal abundances between the two techniques are discussed.
► Ecological assets based exclusively on imagery analyses, e.g. microbial coverage, were included.
► Ecological factors that can be quantitatively assessed based on imagery and sampling at hydrothermal vents are highlighted.