Fouling Communities of Two Accidental Artificial Reefs (Modern Shipwrecks) in Cyprus (Levantine Sea)

Abstract

Abstract:Artificial reefs are considered one of the alternative methods in fisheries management, used in order to enhance stocks and marine biodiversity in general. A number of biotic and abiotic parameters influence the fouling communities' formation on artificial reefs through complex interactions. In order to understand how epibiotic or fouling communities progress through time, it is important to study these communities in mature artificial reefs, especially those that have been around for many decades, or in some cases, millennia. This study was conducted on the coral and other fouling organisms of two accidental artificial reefs (40 to 70 year-old shipwrecks) in Cyprus (Levantine Sea). The thermal and nutrient annual regime of the study sites were characterized by processing satellite data. The results indicate that the wrecks are normally under warm and oligotrophic conditions. Percentage coverage of corals and other organisms on the wrecks was calculated (image-analysis software) on photos taken in 2010 (two wrecks) and again in 2016 (one wreck) of the fouling communities. Sponges were the organisms with the highest percent cover (~27%) at the two wrecks. Four scleractinian coral species were found (7%-19% total coral cover). The oldest wreck, which has well-developed coral communities, was revisited during fieldwork in a near-by area in 2016. Only two major benthic categories (dead coral and macro algae) changed significantly between sampling periods. Given the actual policies to sink wrecks to create artificial reefs and the diverse environmental conditions in different areas that will inevitably influence fouling, it is important to carry out studies relating to mature artificial reefs/wrecks in order to be able to assess the ecological effectiveness of longstanding artificial reefs.

Epibenthic communities associated with unintentional artificial reefs (modern shipwrecks) under contrasting regimes of nutrients in the Levantine Sea (Cyprus and Lebanon)

“…In contrast, on Zenobia, the sites sampled where more sheltered (darker) due to the positioning of the wreck, hence limiting the dominance of algal species. Based on findings published elsewhere [ 19 ], two other modern shipwrecks in Cyprus, Touba and Cricket, showed similar percentage of algae (~15%) as the Zenobia. A detailed description of the algae species in both wrecks most probably will further clarify the trends found in the present study.…”

“…Currents are expected to greatly impact fouling communities as they interfere with larval settlement and food supply as well as sedimentation [ 33 ], hence able to facilitate faster growth. Sites directly exposed to currents are more diverse compared to communities exposed to moderate currents [ 19 ]. It has been also suggested that vertical sites of artificial reefs exposed to direct current, support greater diversity than horizontal surfaces [ 34 ].…”

“…In conclusion, a grid made with 1cm squares was used, representing a point for every 1cm 2 . Under each point on the grid the organism present was identified to the lowest taxonomic level using Mediterranean taxa replacing the program’s original coral code files [ 19 , 23 ]. No areas with image distortion or shade were used.…”

“…The idea for the use of artificial reefs as tools for environmental management was recently adopted by Cyprus [ 19 ]. However, there is a great lack in our understanding of how these structures will perform under the ultra-oligotrophic environment that characterises the Eastern part of the Mediterranean Sea surrounding Cyprus [ 3 ].…”

Epibenthic Communities on Artificial Reefs in Greece, Mediterranean Sea

“…The first deployments of ARs strongly aimed to increase the associated ichthyofauna for the improvement of commercial fishing [3,4]. However, during the last decade, the studies of ARs have shifted towards a more integrated ecosystem approach (e.g., [5,6]), in order to understand the communities colonizing the ARs, and how to use the gained knowledge for habitat "rehabilitation" and "restoration" [4,[7][8][9][10][11][12][13].…”