Involving fishers in scaling up the restoration of cold-water coral gardens on the Mediterranean continental shelf

Abstract

Cold-water gorgonians dwelling on the continental shelf are a common by-catch of bottom-contact fishing practices. Given the slow growth and limited recruitment of coldwater gorgonians, impacts derived from fishing activities may seriously compromise the conservation of the highly complex coral gardens which they generate, as well as the abundant and highly diverse associated fauna. For this reason, the development of effective active and passive restoration methods is nowadays a priority to enhance the natural recovery of impacted cold-water coral gardens. However, ecological restoration of mesophotic and deep-sea communities remains extremely limited, due to their technological requirements and associated costs bringing their wide-scale and longterm application into question. This study reports the results of the first large-scale active restoration of more than 400 cold-water gorgonians on the Mediterranean continental shelf. By actively involving local fishers during two consecutive fishing seasons, by-catch gorgonians were recovered and returned to the continental shelf (at 80-90 m depth). Two-years monitoring performed through Autonomous Underwater Vehicle (AUV) surveys revealed that 460 gorgonian transplants survived over an area of 0.23 ha. This reintroduced cold-water gorgonian population is compared to a reference natural population in terms of size and spatial structure. The cost of the restoration amounted to 140 000 €/ha, which is significantly less than for any deep-sea restoration actions performed to date. The success of this cost-effective activePowered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation restoration highlights the viability of large-scale restoration of impacted cold-water coral communities, with promising results for the conservation and recovery of mesophotic and deep-sea ecosystems.

An urgent call for more ambitious ocean literacy strategies in marine protected areas: a collaboration project with small-scale fishers as a case study

“…Considering the fishing habits of small-scale fishers (fishing in around 90 m depth) in Cap de Creus MPA, these species were considered as the more suitable study species for restoration purposes. The RESCAP project offered a framework to recover gorgonians entangled in small-scale fishing nets, apply restoration methodologies, and return the specimens to natural areas for consequent monitoring to develop a pilot project (Montseny et al, 2021;Grinyóet al, 2022). On the other hand, the MITICAP project emerged to implement measures to mitigate the fishing impacts caused by small-scale fishing in the Cap de Creus MPA (Santıń et al, 2022a).…”

“…The restoration project was mainly focused on the bycatch colonies of cold-water corals and soft corals, being Eunicella cavolini (Koch, 1887) the most abundant gorgonian found and returned. The methodology used to recover and return the specimens was following the approach of Montseny et al (2021). In brief, the gorgonians recovered from fishing nets were transferred to experimental aquariums in the fishing guild (for Port de la Selva) or a local from the Cap de Creus Natural Park (for Cadaqueś-Port Lligat).…”

“…Therefore, along with marine conservation and ecosystem restoration several OLactions were also developed in the context of MITICAP and RESCAP to expand the dissemination of the scientific knowledge of the projects. Both projects highlighted the importance of collaborative studies between fishers and scientists for marine benthic studies, with contributions on the study of the economic viability of joint conservation activities, the implementation of mitigation measures for reducing the impacts of fishing in the study area or the detection of possible threats to marine biodiversity (Montseny et al, 2021;Santıń et al, 2022b;Biel-Cabanelas et al, 2023;Higueruelo et al, 2023). However, important dimensions related to social and educational aspects were not previously analyzed and reported.…”

Diversity, structure and spatial distribution of megabenthic communities in Cap de Creus continental shelf and submarine canyon (NW Mediterranean)

“…For this reason, specific actions should be taken to promote the conservation of shelf-dwelling gorgonian populations, which can be of key importance in promoting local diversity in low complexity habitats, and whose long-term viability could be severely affected by the effect of fishing practices. Besides improving their protection, restoration measures could also be considered an effective approach to improve the conservation of these populations, such as the cost-effective actions already implemented in Cap de Creus in collaboration with local fishers to reintroduce by-catch colonies back into their habitat (Montseny et al, 2021).…”

Habitat loss and small‐scale fishery: A controversial issue

“…Few attempts have been carried out to increase the selectivity and reduce fish discard by developing experimental bottom nets for SSF (Briggs, 2010; Kalayci & Yeşilçiçek, 2014; Lucchetti et al., 2020; Priester et al., 2021). However, the very limited evidences focusing on bycatch composition of unmarketable invertebrates show that fishing activities can determine significant impacts on the benthic communities (FAO, 2018) directly removing habitat‐forming species (Enrichetti et al., 2019; Eryasar et al., 2020; Gil et al., 2018; Gonçalves et al., 2008; Montseny et al., 2021) or losing the nets and fishing gears on the bottom (i.e., ghost net: Bo et al., 2014; Ferrigno et al., 2018; Betti et al., 2020) mainly due to bad weather conditions (Ozyurt et al., 2012).…”