Coupling the map of marine habitats and fish accumulation zones : a three-dimensional spatial approach for the management of halieutic ressources.
Year: 2020
Type: article
Abstract: The spatialisation of halieutic data is an essential element to define and create efficient protected and managed areas. Moreover, the distribution of fish schools is not homogeneous in the water column and is strongly linked with marine habitats. It is thus necessary to develop techniques allowing a spatial evaluation of halieutic resources. Multibeam echo sounders (MBES) provide acoustic data of the seafloor and the water column with a high accuracy and resolution. A single acquisition gives the bathymetry, a backscatter mosaic of the sea bottom and an acoustic imagery of the water column. The bathymetric data processing highlights the seafloor rugosity using several metric indices. A semi-automated classification including the depth, the rugosity indices and the backscatter values provides maps of marine habitats which are finally validated with ground truth. Data from the water column are analysed using an algorithm that detects acoustic targets corresponding to fishes. A georeferenced scatter graph of fish schools is thus automatically created. The 3D model of the seafloor obtained from the bathymetry is textured with the map of marine habitats. Points corresponding to fish detection are then added on the 3D model to provide a complete map. Through this process managers can access to a clear visualization of fish accumulations and the key marine habitats within their areas of interest.
Source: HAL
Language: English
Subfield: Aquatic Science
Domain: Life Sciences
SDG: Life below water
Open Access status: green
OpenAlex ID: W4285752899