Prof. Roger Herbert1, Ms Jessica Bone1, Dr Alice Hall2, Prof Stephen Hawkins3, Prof Rick Stafford1
1Bournemouth University, Poole, United Kingdom, 2Plymouth University, Plymouth, United Kingdom, 3Southampton University, Southampton, United Kingdom
Much hard marine infrastructure along urban coasts has relatively low complexity and smooth surface texture, which results in poor habitat for marine organisms. Yet small-scale experiments have demonstrated improvements through the creation of habitat features such as holes, pits, grooves and rockpools. To confidently adopt these enhancements, asset managers and engineers need more guidance on the number, density and position of features required to significantly improve biodiversity on structures.
We present results of a trial using 90 concrete artificial rockpools over two sites to measure the benefits of retrofitting different configurations of pools to sea walls on the south coast of England. At each site we fixed 1, 3 or 5 concrete rockpools in horizontal rows within 2m wall sections at Mean High Water Neap tide level. Each configuration was replicated (n=5) over an 80m section of sea wall. Over 24 months we monitored changes in species abundance, biomass, richness, and assemblage composition in the interior and on the exterior of the pools, the whole wall section including zones above and below the pools (High Water Springs – Mean Tide Level) and in control sections of the sea wall without rockpools. By the end of the trial, at each site, wall sections with five pools had a significantly different assemblage composition and higher species richness compared to sections with single pools and control sections, yet there was little difference between sections with 3 and 5 pools. Planning tool metrics were also employed to guide decision making for coastal managers.
Biography:
Roger is Professor of Marine and Coastal Biology at Bournemouth University, UK. He works mostly on climate-related disturbances and impacts on coastal marine ecosystems. He has a particular interest in intertidal ecology and the marine biogeography of the North-east Atlantic and English Channel. Part of his professional practice develops climate change adaptation strategies that incorporate ecological design to restore and enhance biodiversity within marine structures (sea walls, breakwaters and coastal lagoons). He also works on the ecology and management of marine invasive species and inshore fisheries.
