A guide for planners and managers - IUCN

198 MARINE AND COASTAL
PROTECTED AREAS
2.5 Design of the Marine Protected Area
Regardless of how small or how large the portion of the lagoon or estuary that is
intended for an MPA, it is necessary to address the entire estuarine ecosystem. When
you cannot designate a whole estuary as an MPA, we suggest using one of the
techniques mentioned above and either 1) attempt to invoke CZM for the whole
estuary, or 2) attempt to set up a ZOI coordinating entity.
The policy of the planner should be to design the protected area following
procedures like those described herein. First a strategy should be worked out and a
Strategic Plan created. Second a Site Management Plan should be created with
specific mechanisms for periodic review and any needed revisions of design based
on new management studies. Assuming no initial expert assistance and little knowledge
of the life histories of estuary-dependent species, the protected area should be
designed to encompass as many habitats as possible.
The actual design work should follow the procedure in the earlier chapter on
site planning (Section I-2). The objective is to design the lagoon or estuarine protected
area around its principal habitats as revealed by field surveys of flora and fauna. The
number of zones, if any, and the size of the protected area will depend on management
objectives, examples of which are listed in Table II-12. Conserving estuary-dependent
commercial species may require protecting a range of critical habitats both inside
and outside the estuary.
2.6 Identifying Critical Habitats
Managing an estuary requires protecting the critical habitats of estuary-dependent
species. The identification of these sites and processes requires knowing the geographic
biology, particularly the life histories of key estuarine organisms. Each species has a
characteristic requirement including substrate type, water depth, water clarity,
dissolved oxygen content, and type of habitat (e.g., mangrove prop roots, marsh
grass, or sea grass stems). And each key species has critical habitats that it uses during
its life cycle. Such critical habitats are numerous and diverse (Box II-1).
Many habitats, perform special nurturing functions for certain species, including
low intertidal marshes, high marsh tide pools, mangrove swamps, swamp and marsh
creeks, mud and sand flats, passes or openings to the open ocean, open beaches, sea
grass beds, macroalgae beds, rocky shores and tide pools, and many types of coral
reefs, from patch reefs to extensive barrier reefs.
If the MPA is nested within a CZM area, special habitats may be identified for
different categories of management, not just MPA management. Examples of three
such categories previously discussed in Section II-5.8 are: 1. Generic habitat types; 2.
Specific sites (critical areas); and 3. MPAs.