Monitoring of ExoHabitats in the Hamble
This summer, three-year biodiversity surveys were completed on six ExoHabitats which were installed on the harbour wall at Mercury Yacht Harbour on the River Hamble, Hampshire in 2020. Using our Greening the Grey® technology, the ExoHabitats include surface textures and artificial rockpools designed to enhance biodiversity by providing unique niches for marine species.
During low tide, all species present on the ExoHabitats were recorded, along with those found on control areas of adjacent sheet piling at the same tidal height for comparison. In addition, a Remotely Operated Vehicle (ROV) was also deployed to capture high-definition video of the ExoHabitats, sheet piling, and surrounding habitat during high tide.
Our results show that these artificial structures have attracted a diverse range of marine species through the creation of vital niches to foster their growth. In total, twice as many species were recorded on the ExoHabitats compared to the control areas of sheet piling. The control sheet piling areas were predominantly dominated by filamentous green algae and barnacles. In contrast, the ExoHabitats created additional niche habitats that allowed a broader range of species to colonise, including several different seaweeds, keel worms, and oysters.
The inclusion of the artificial rockpools in the design proved crucial. Not only have the cups created a water-retaining feature for intertidal species, but the underside of the artificial rockpools provide additional shade, attracting a greater abundance of oysters, keel worms and barnacles compared to the control sheet piling at similar tidal positions. ROV footage revealed that many of the species recorded were thriving at the base of the harbour wall beneath the lowest level of the ExoHabitats, an area which remains submerged at all states of the tide. This suggests that the ExoHabitats are creating essential niches that extend their habitat range, enabling these species to survive in areas where desiccation would typically prevent this. Furthermore, an interesting "halo effect" was observed, with some of the additional species found on the ExoHabitats also appearing on the sheet piling directly surrounding the units. This suggests that the ExoHabitats may be extending their biodiversity benefits to the surrounding ecosystem
This innovative approach to marine conservation showcases the potential for human-made structures to contribute positively to the health and diversity of marine ecosystems, demonstrating how we can work with nature to mitigate the challenges of environmental change and habitat loss. By implementing similar initiatives in other coastal areas, we can contribute to the preservation and restoration of our oceans' delicate ecosystems, providing hope for a more sustainable future.
