The country conservation agencies are also required to advise relevant authorities as to any operations which may cause deterioration of habitats or disturbance to species for which the site has been designated (Regulation 33(2)). This advice on operations will inform the development of the management scheme, by enabling relevant authorities to focus attention and management actions where needed on those activities, under their control, that pose the greatest potential threat to the favourable condition of interest features on the site. The approach for issuing this advice is currently being developed by the country conservation agencies (Burt et al in preparation; Cooke & McMath in preparation).

In order to support the process of providing clear and concise advice, the processes or factors that link the operation with ecological requirements of the interest features will be identified. For example, the key processes or factors that may result from a dredging operation include, siltation, direct physical damage, and changes in levels of toxic and non-toxic (suspended sediments, turbidity, and nutrient/organic enrichment) contaminants. This common approach has been adopted by the different country conservation agencies, however the terminology used by each varies slightly. The advice given by English Nature will be provided under six broad categories of operations which may cause deterioration or disturbance (physical damage), each of which are subdivided into a number of component effects or processes (abrasion and selective extraction) that link the operational category to the interest feature (see linked table).

A similar approach has been adopted by CCW (Cooke & McMath in preparation) who characterise each maritime activity by a series of seven component effects or primary factors (physical disturbance), which can be subdivided into secondary (abrasion and removal) and tertiary factors. Work is currently in progress to move towards using common terminology. However in both cases the methodology is appropriately robust to reassure relevant authorities that despite the huge range of maritime activities, it is possible to have a relatively definitive list of factors/processes and once issued the advice should need only infrequent review.

The operations to which the marine features and sub-features of a site are most vulnerable can be identified on a site-to-site basis by considering their sensitivity to the effects of the processes/factors and their exposure to those processes/factors to which they are sensitive. This will be achieved by using simple, user-friendly tables against which relevant authorities can assess the activities under their jurisdiction.

The advice on operations is provided in the light of current activities and patterns of usage at the site. It is important that future consideration of this advice takes account of changes in the usage patterns that have occurred at the site. In contrast, the sensitivity of the interest features, or sub-features, is relatively stable and will only change as a result with an improvement of scientific knowledge. Advice for sites will be kept under review and may be updated from time to time through discussions of the relevant authorities and other interested bodies.

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