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Individual study: First results of fauna community structure and dynamics on two artificial reefs in the south of the Bay of Biscay (France)

Published source details

Castège I., Milon E., Fourneau G. & Tauzia A. (2016) First results of fauna community structure and dynamics on two artificial reefs in the south of the Bay of Biscay (France). Estuarine, Coastal and Shelf Science, 179, 172-180

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Create artificial reefs Subtidal Benthic Invertebrate Conservation

A study in 2009–2013 of two artificial reefs in the southern Bay of Biscay, North Atlantic Ocean, France (Castège et al. 2016) found that artificial reefs hosted at least five to seven species of large mobile invertebrates. Five species were recorded in Porto artificial reef, with two recorded during >75% of dives (edible crabs Cancer pagurus; velvet crabs Necora puber). Seven species were recorded in Capbreton artificial reef, with one recorded during >75% of dives (the common octopus Octopus vulgaris) and two recorded during 50–75% of dives (the common prawn Palaemon serratus; the velvet crab). Other large mobile invertebrate species recorded in lower frequencies included European spider crabs Maja brachydactyla, hermit crabs Pagurus bernhardus, and common cuttlefish Sepia officinallis. Porto artificial reef was created in 1994 and made more complex over time until 2004. Capbreton artificial reef was created in 1999 and made more complex in 2010. Both reefs were made of barges, concrete modules and pipes, and were located on sandy seabed at 12–25 m depth, 84 km and 20 km away from the nearest rocky shore, respectively. Anchoring, diving, and all types of fishing were prohibited. Annually between 2009–2012 (Porto) and 2010–2013 (Capbreton), 2–4 stations/artificial reef were surveyed during 2–5 dives/station. During each dive, two divers visually recorded and counted the number of large mobile invertebrate species in a 2 m radius circle for 3 min. Frequency of occurrence was calculated for each species as: (number of dives in which the species was counted/total number of dives) Х 100.

(Summarised by Anaëlle Lemasson)