Impact of fishing activities on different coralligenous assemblages of Gulf of Naples (Italy)

Abstract

Coralligenous bioconstructions are among the most important Mediterranean habitats for biodiversity maintenance. However some characteristic and sensitive organisms, such as the fan corals, are considered endangered in the international community; indeed, they may be severely damaged by fishing activities causing mechanical damage and increasing sedimentation rate. ROV (Remotely Operated Vehicle) investigations were carried out in order to characterize different morphological types of coralligenous habitat (rim, bank and shoal) located in the southern Bay of Naples (Italy), and to assess the presence of lost fishing gears and their impact on these benthic communities. A rapid classification of different fishing pressures and impacts was obtained through the development of new, representative and synthetic categories. Image analysis revealed the presence of rich and diversified communities, characterized by several fan coral colonies. However, fishing activity dramatically affects these coralligenous habitats, entangling and covering benthic assemblages and leading to necrosis and to parasitic epibionts growth especially on branched organisms. Monitoring programmes may provide a detailed assessment of coralligenous habitats characterization, distribution and health status. An accurate evaluation of fishing pressure and impact may be considered a useful tool to improve sustainable management of these valuable habitats.

Detailed Mapping of Hydrothermal Vent Fauna: A 3D Reconstruction Approach Based on Video Imagery

“…Mussels of the genus Bathymodiolus are founder species that structure the community (Gollner et al, 2015;Du Preez and Fisher, 2018) and increase community dynamics (Breusing et al, 2015;Ferrigno et al, 2017). In accordance with findings of Sen et al (2014), the Bathy4 assemblage had the highest total abundance of all faunal assemblages (Table 2), despite not covering the largest surface area (Figure 5B).…”

“…Especially at vertical chimney structures above black-and diffuse fluid exits, larger individuals were recognized but we did not test for significance. These areas are influenced by hydrothermal fluids with high temperatures and low oxygen levels (Beauchamp et al, 1984;Podowski et al, 2010), but may resemble submarine canyon conditions with vertical cliffs and overhangs, which provide exposed structures, suitable for sessile, and filter feeding anemones (Ferrigno et al, 2017).…”

Assessing molluscs functional diversity within different coastal habitats of marine protected areas

“…As a consequence, conservation policy and management strategies for these habitats have been more and more implemented in the last decades (Cicin-Sain and Belfiore, Italian shores, Marine Protected Areas (MPAs) have been instituted by the law 394/91 and, together with the Habitat Directive (92/43/EEC) on European species and habitats of priority importance for conservation, they represent a useful tool to protect marine biodiversity and to implement sustainable practises of coastal zone management (Browman et al, 2004;Halpern et al, 2010;Rassweiler et al, 2012). Several studies demonstrate the effectiveness of MPAs for the conservation of marine biodiversity (Appolloni et al, 2017Ferrigno et al, 2017Ferrigno et al, , 2018, the increase of ecosystem services and the production of ecological and economic benefits that are exported in the surrounding coastal areas (i.e., Guidetti et al, 2008;Fenberg et al, 2012;Franzese et al, 2008;2015;Picone et al, 2017). In this framework, it is very important to assess how the assemblages of those systematic groups, as molluscs, with high levels of biodiversity are structured.…”

Response diversity in Mediterranean coralligenous assemblages facing climate change: Insights from a multispecific thermotolerance experiment

“…Coralligenous assemblages are biogenic formations built by the growth of crustose coralline algae and diverse calcareous macroinvertebrates at low irradiance levels and are characterized by their great structural complexity and species richness (harbouring ~10% of marine Mediterranean species) (Ballesteros, 2006). Most of the structural species of these habitats exhibit slow population dynamics and long life spans (+100 years; Garrabou & Harmelin, 2002;Linares, Doak, Coma, Diaz, & Zabala, 2007;Teixidó, Garrabou, & Harmelin, 2011); therefore, they are very sensitive to disturbances, including climate change (Balata, Piazzi, & Benedetti-Cecchi, 2007;Ferrigno, Appolloni, Russo, & Sandulli, 2018;Garrabou et al, 2009;Montero-Serra et al, 2015). In fact, more than 30 coralligenous species from different phyla and different structural roles have been affected in various mass mortality events (hereafter MMEs) associated with Mediterranean heat waves, suffering extensive tissue necrosis (partial and total mortality) and long-term population declines (Cerrano et al, 2000;Crisci, Bensoussan, Romano, & Garrabou, 2011;Garrabou et al, 2009;Garrabou, Perez, Sartoretto, & Harmelin, 2001;Linares et al, 2005).…”