Addressing Cetacean–Fishery Interactions to Inform a Deep-Sea Ecosystem-Based Management in the Gulf of Taranto (Northern Ionian Sea, Central Mediterranean Sea)

Abstract

Understanding of cetaceans’ trophic role and the quantification of their impacts on the food web is a critical task, especially when data on their prey are linked to deep-sea ecosystems, which are often exposed to excessive exploitation of fishery resources due to poor management. This aspect represents one of the major issues in marine resource management, and trade-offs are needed to simultaneously support the conservation of cetaceans and their irreplaceable ecological role, together with sustainable fishing yield. In that regard, food web models can represent useful tools to support decision-making processes according to an ecosystem-based management (EBM) approach. This study provides a focus on the feeding activity occurrence and the trophic interactions between odontocetes and the fishery in the marine food web of the Gulf of Taranto (Northern Ionian Sea, Central Mediterranean Sea), by zooming in on cetaceans’ prey of commercial interest. In particular, the quantification of trophic impacts is estimated using a food web mass-balance model that integrates information on the bathymetric displacement of both cetaceans’ prey and fishing activity. The results are discussed from a management perspective to guide future research and knowledge enhancement activities as well as support the implementation of an EBM approach.

Mitochondrial DNA diversity and genetic structure of striped dolphin Stenella coeruleoalba in the Northern Ionian Sea

“…The complex morphology of the area together with the circulation of water masses involve the occurrence of seasonal and decadal upwelling currents (Civitarese et al, 2010;Matarrese et al, 2011;Carlucci et al, 2014;Pinardi et al, 2016) playing a significant role in sustaining productivity (Capezzuto et al, 2010;Maiorano et al, 2010;Carlucci et al, 2018;Ricci et al, 2019) and favouring the occurrence of valuable habitats from the conservation perspective such as the Santa Maria di Leuca cold-water coral province (D'Onghia et al, 2016;Vassallo et al, 2017) and those inhabited by several species of cetaceans (Bellomo et al, 2019;2020c;Carlucci et al, 2018b;Carlucci et al, 2018c;Carlucci et al, 2020a;Carlucci et al, 2020b;2021a;Santacesaria et al, 2019;Cipriano et al, 2022). Unfortunately, the basin is potentially affected by several human pressures or threats resulting in possible direct and indirect impacts on cetaceans (Carlucci et al, 2021;Ricci et al, 2021).…”

An ecosystem-based system of variables to enhance marine species and habitat monitoring and conservation: The Adriatic Natura 2000 case study

“…For the same reasons, "genetic diversity" has a low score, being also considered only by EBVs. Also, "prey abundance" and "prey distribution" obtained low scores; they are absent from both directives and their monitoring is not advantageous in terms of cost-benefit ratio, although better information on the bottlenose dolphins' diet is necessary (Ricci et al, 2021). Furthermore, both these variables cannot be monitored by citizens, or used for ES assessment.…”

Initial results on the variation of whistle characteristics of bottlenose dolphins from two neighbouring regions of the Mediterranean Sea: Northern Ionian and Southern Adriatic Sea

“…Cetaceans are recognized as key top-level controllers in marine ecosystems due to their roles in preserving the structure and function of marine communities (Heithaus et al, 2013;Ricci et al, 2021;Carlucci et al, 2021). The ecological health and population status of cetaceans can potentially be used as bio-indicators for the assessment of ecosystem health (Wells et al, 2004;Paudel et al, 2020).…”