An evaluation of artificial reef structures as tools for marine habitat rehabilitation in the Maldives

Abstract

1. In the Maldives, coral mining for the construction industry has resulted in widespread degradation of shallow reef‐flat areas. Due to the loss of these coastal resources and the associated problems of coastal erosion, there is an urgent need to find practical methods for rehabilitating mined reefs. 2. The slow rates of natural recovery of mined reefs has prompted interest in the potential of artificial reef structures to rehabilitate these degraded habitats. An experimental artificial reef programme was initiated in 1990 to discover whether it is feasible to use a bio‐engineering approach to kick‐start natural reef recovery. 3. The main goals of the project were to restore the capacity of degraded reefs for sea defence and their ability to harbour fish species. Accordingly, 360 t of concrete structures of varying levels of topographic complexity, stabilising effect and cost were deployed on a heavily mined study site close to the capital island, Malé. 4. Within 1 year of deployment, the artificial reef structures had similar or greater species richness and densities of reef fish than did control pristine reef flats. However, the community structure of the fish populations on the artificial reef structures was significantly different to that on unmined reef flats. 5. Preliminary results of a monitoring programme indicated that substantial coral recruitment had occurred on the larger reef structures which were each supporting ca. 500 colonies, some of which were approaching 25 cm in diameter after 3.5 years. An evaluation of the effectiveness of the various artificial reef structures is discussed in relation to their design features and costs and in line with timescales for the recovery processes. Copyright Copyright © 1999 John Wiley & Sons, Ltd.

The influence of offshore windpower on demersal fish

“…The construction and deployment of so-called artificial reefs, ranging from specially designed concrete or steel units to scrap materials such as car tyres and shipwrecks, is a widely used tool to enhance fisheries, to mitigate damage to the environment, to protect or rehabilitate certain habitats, or to increase the recreational value of an area (Hueckel et al, 1989;Milon, 1989;Ambrose, 1994;Brock, 1994;Chua and Chou, 1994;Guillén et al, 1994;Pickering et al, 1998;Rilov and Benayahu, 1998;Wilhelmsson et al, 1998;Clark and Edwards, 1999;Jensen, 2002). So-called secondary artificial reefs (Pickering et al, 1998), constructed for other purposes, such as oil platforms (Seaman et al, 1989;Rooker et al, 1997;Love et al, 1999;Helvey, 2002;Ponti et al, 2002), breakwaters (Stephens et al, 1994), pier pilings, and pontoons (Rilov and Benayahu, 1998;Mocquet et al, 1999), also serve as habitats for fish and invertebrate assemblages.…”

Processes limiting mussel bed restoration in the Wadden-Sea

“…suggesting that other factors such as hydrodynamic stress or predation may be hindering restoration efforts (Clark and Edwards 1999, Luckenbach et al 2005, Christianen et al 2014. It is therefore likely that restoration of ecosystem engineers may require a multifaceted approach that addresses the interplay between several limiting factors.…”

Epibenthic Communities on Artificial Reefs in Greece, Mediterranean Sea

“…This provides helpful insights on improving future AR deployments by better understanding the outcome of the main parameters affecting the community composition on the ARs, such as design, material, and geographical location. Furthermore, the fact that the three ARs share a widely used material [7,33,55] and that they are located in contrasting environmental areas makes the results of this study more easily applicable on a greater geographical scale for future AR deployment in similar environmental areas.…”