Wrecks on the Seabed: Ecology

As part of two major projects: the ALSF funded Wrecks on the Seabed project and the contract to implement the Protection of Wrecks Act (PWA) for English Heritage (now Historic England), Wessex Archaeology’s dive team has surveyed more than 65 shipwreck sites around the coast of the United Kingdom.
These diving surveys have generated a substantial body of information about each site and as we have processed this information it has become increasingly clear that the relationships between wrecks and the plants and animals that inhabit them is a neglected area of study and one that needs closer scrutiny.
The contexts of these two projects - the mitigation strategies generally adopted for wrecks within aggregate extraction areas in the case of Wrecks on the Seabed, and the conservation and management of protected sites in the case of the PWA – have thrown up a number of questions about the relationships between wrecks and their flora and fauna.
For example, do historical wrecks have nature conservation value in terms of the species they attract or the habitats they provide? Where wrecks are surrounded by exclusions zones – such as in aggregate extraction areas – do they act as refuges for species, or habitats from which the re-colonisation of adjacent areas of the seabed can take place after aggregate dredging? Can the presence of species or character of habitats be used as a proxy for gauging wreck site condition and stability? And is there any scope for, or value in, integrating archaeological and ecological surveys of wreck sites?
With these questions in mind we approached Dr. Kate Cole (East Sussex County Council – Coastal Biodiversity Officer/Sussex Seasearch Co-ordinator) and Dr. Gerald Legg (Brighton and Hove Council – Marine Biologist, Booth Museum). We showed them some of the photographic data we’d collected, and asked them whether such information, gathered during archaeological site assessments, would be useful to them as ecologists. And if so, what might be done to incorporate ecological and biological recording into archaeological survey work?
Their response was that this data was useful for biological and ecological purposes and could, for example provide evidence of key indicator species that are ‘moving’ as a result of climate change or are otherwise significant.
From an archaeological perspective these discussions suggested that this information can be used to more accurately describe the biological condition of wrecks, including the variability across wreck sites, by studying the environmental processes at play, as indicated by different species.