Advances in the Assessment of Habitat Fragmentation and Protection in the NAFO Regulatory Area
2022
Sacau-Cuadrado, María del Mar | S. Wang | E. Kenchington | Murillo, Francisco Javier | C. Lirette | M. Koen-Alonso | A. Kenny
NAFO has used kernel density analyses to identify VMEs dominated by large-sized sponges, sea pens, small and large gorgonian corals, erect bryozoans, sea squirts (Boltenia ovifera), and black corals. That analysis generates polygons of significant concentrations of biomass for each VME indicator which are spread across the spatial domain of the NAFO fishing footprint. There is potential for bottom contact fishing to induce changes in both the amount and configuration of habitat (e.g., decreased polygon size, increased polygon isolation, and increased edge area) through direct and indirect impacts, and it is unknown to what degree such changes may already have taken place given the long fishing history of the area. In the Report of the 13th Meeting of the NAFO Scientific Council Working Group on Ecosystem Science and Assessment (WGE-ESA), preliminary work on assessing and monitoring habitat fragmentation was presented. Here we continue that work by recalculating the indices after removing connections that are not identified through particle tracking models. We have reanalyzed the nearest neighbour distances and PX, a proximity index, for the VME polygons noted above, and for the new closed areas that will come into effect 1 January 2022. We show that PX when applied to the new closures appears sensitive to their spatial configuration which bodes will for the ability of this index to identify habitat fragmentation in the future, brought about through fishing activities and/or natural disturbances.
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