project attempts to carry out the 

 objectives of the Coastal Act while 

 resolving the political, economical and 

 ecological conflicts which surround each 

 wetland. Scientists have been brought 

 into the planning phase of these projects, 

 and procedural guidelines are emerging. 

 This section discusses several design 

 concepts which should be considered in 

 planning for wetland establishment or 

 enhancement, and then summarizes the 

 ecological capabilities and problems 

 inherent in implementing such projects. 



Ecological Concepts For Designing Wetlands 



Developing priorities for the types 

 of species and habitats which should be 

 preserved or enhanced often leads to 

 attempts to put values on natural 

 resources. Those species which have 

 become so reduced in numbers that they 

 achieve endangered status often are given 

 special consideration, and whole 

 developments have been halted for concern 

 over a single species. Yet it would seem 

 that all native species deserve our 

 concern, just as all natural ecosystems 

 deserve consideration in our overall 

 management outlook. Ehrenfeld (1976) has 

 pointed out the fallacies of attaching 

 various economic values to native species. 

 Clearly, some have important economic 

 ramifications, e.g. species valued in 

 hunting, fishing, used in producing 

 valuable natural products, etc. But many 

 do not. These, he says, should be 

 recognized for what they are: Valuable 

 but "non-economic resources." 



Because there are several endangered 

 species which inhabit southern California 

 coastal wetlands, much of the argument for 

 preserving, conserving, restoring, and 

 enhancing these wetlands focuses on 

 selected species (Table 18). At the same 

 time, the California Coastal Act calls for 

 maintenance and enhancement of the 

 wetlands as a whole. Most of the 

 endangered species probably owe their 

 reduced population size to reductions in 

 habitat, so there would seem to be no 

 conflict in managing for individual 



species or for wetland ecosystems. Where 

 a functioning wetland exists, maintain its 

 natural features. However, in designing 

 modification of disturbed habitat and 

 developing mitigation plans for wetland 

 alterations, the first question is what 

 type of habitat should be created. Should 

 habitat for the most endangered species 

 (if that could be determined) take 

 precedence? Or, at the opposite extreme, 

 should some of all types of habitats be 

 incorporated in the "landscape design"? 

 Like the new shopping center, should each 

 wetland project have its fast food outlet 

 (fly-over fish pond), supermarket (mud- or 

 sandflat feeding ground), parking lot 

 (roosting area), boutique (site for rare 

 but interesting species) , and department 

 store (intertidal marsh complex)? 



At this stage, some comments, but few 

 conclusions, can be made. Critical to the 

 discussion is understanding the optimum 

 areal distribution of habitats for 

 maintenance of native species. Management 

 plans must take into account the 

 management needs, not only of the local 

 area, but also of the entire region and 

 beyond. Plans should not be developed 

 independently, without regard for other 

 projects, but should proceed mutually with 

 consideration of how both regional and 

 local objectives can best be met. Once 

 these objectives are understood, the 

 question of area and distribution of areas 

 can be considered. The principles of 

 island biogeography (MacArthur and Wilson 

 1967) might assist the decision- making 

 process. Generalizing from what we know 

 about islands, we would expect big wetland 

 areas to attract and support a larger 

 number of species (especially birds), and 

 that wetlands close to a source of species 

 would have a higher probability of being 

 colonized by those species than would 

 distant wetlands. 



Ecological Aspects of Restoring Marshes 



Several plans for restoring wetlands 

 have been proposed throughout California 

 and a few are in the implementation 

 phases. The biggest project in southern 



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