150 The Essex Naturalist local authorities. In the international sphere, suitable sites have been designated as Wetlands of International Importance (under the Ramsar Convention), Special Protection Areas (under the EC Birds Directive) and candidate Special Areas of Conservation under the European Habitats Directive. Of course, all the designations in the world will not necessarily protect special sites against large-scale changes. Drought, to which Essex is increasingly prone, is one such factor, and sea level rise as a result of global warming is another. Such problems require a strategic response in order to manage the changes as effectively as possible. Finally, we do recognise that there are elements of the native flora and fauna of Essex which are inadequately represented and protected by means of SSSI notification. Given the large woodland resource of the county, it may be that further SSSIs are appropriate, and the Markshall Woods complex has already been mentioned in this respect. With improved natural history knowledge, new interest features have been identified on certain sites, which will require re- notification in order to fully protect them. Thus, two geological SSSIs (The Naze and Harwich Foreshore) should perhaps be re-notified to reflect their biological interest (invertebrates and rocky shore habitat, respectively). But perhaps the single most important, largely unprotected wildlife resource is the diverse invertebrate fauna of the south Essex terrace gravels; critically, this is also one of the most threatened resources. However, given the opportunistic nature of such invertebrates, often occupying individual sites only temporarily, that it may be the essentially static, site-based mechanism of SSSI designation is not appropriate to conserve them. The role of Essex naturalists The amateur naturalist has long played an important role in SSSI designation, by providing information about the important species on a site, and in contributing records to national databases which allow accurate assessment of species abundance, distribution and status. This role is still as important now, to ensure our knowledge about sites is as up to date as possible and to monitor the success or otherwise of management practices. Moreover, given the current initiatives designed to maintain and enhance biodiversity, monitoring of the achievements of species and habitat action plans is crucial to guide the effective deployment of what are always limited resources for conservation. The natural world is always in a state of flux. At the present time, this is all too apparent as nature responds to environmental changes such as global warming. Climatologists may make predictions about what is likely to happen, but rarely can they make definitive statements, particularly when they have professional reputations at stake. But individual species do not have those concerns: if the environment changes, they will respond. The vital role of the modern naturalist is to identify what changes are taking place, allowing those