Page 268 - Manual for Activities directed at the Underwater Cultural Heritage

nagement process in order to conduct diagnostic assessments and monitoring.
Boats, working and surface platforms must have fixed moorings, so that regular recasting of anchors is avoided. Even in sandy areas anchors have quite considerable impact, whereas mooring in sea grass or seaweed beds may destroy these. Of course one would not want to cast anchors on archaeological remains.
Introduction of species
In some areas, particular care must be taken to avoid the introduction or spread of invasive species. The seaweed Caulerpa taxifolia, though beautiful, is considered a disaster outside its original habitat. The same is true for several bivalve species, crustaceans and fish. Although ensuing ecological problems may be extensive, and although they are important in marine environmental policies that deal with the movement of ships and their operators, they are not typical for the management of archaeological sites. Let us not – although we could – count the visiting humans under this kind of invasive species. Public enjoyment is after all an important reason to devise a site management plan in the first place.
The impact of offshore activities and fishing on underwater cultural heritage
Discussions on the environmental impact of offshore operations, as for instance, drilling for oil-wells, pipe- or cable- laying, date way back. Impact studies and mitigation have been identified as the most adequate answer to the environmental impact of offshore operations. These impact studies address the potential presence of archaeological sites and heritage of significance with the same logic as other environmental factors. Although there is certainly room for improvement, this approach works
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Environment