1. The index, be it dominant species type or whatever, must be 

 linked backward to measures of ambient water quality, which in 

 turn are linked to levels of pollution discharge. 



2. There must be an a priori reason to expect participation decisions 

 to reflect values of the index. 



3. Data must be available to test the hypothesis from 2 and in the 

 process to product projection equations for participation as a function 

 of the index. 



In moving from freshwater to saltwater recreational fishing, several 

 possibilities for this key index present themselves. An obvious candidate is 

 dominant species, as in freshwater, and there exists some evidence that this 

 effect can be significant, at least for well-defined bodies of water such as 

 enclosed bays and estuaries. Resident populations within semi-enclosed marine 

 waters with serious pollution problems apparently are dominated by such fish 

 species as bay sardines and toadfish. Marine gamefish such as bluefish and 

 striped bass do not seem to frequent dirty areas, nor do they use contaminated 

 estuaries for spawning or nursery areas, but because of the tremendous available 

 dilution and the mobility of major marine species, it seems unlikely that any 

 significant fraction of the nearshore ocean would be found to be dominated by 

 low quality species (e.g., U.S. Department of the Interior 1970, Sindermann 1975, 

 McErlean et al. 1972). 



A second possibility for the index is some measure of fish population 

 (numbers, or average size, for example) as a proxy for prospective success in 

 angling (bag). This was the basis of the benefit estimation procedure used by 

 Bell and Canterbery in their major study (1976). There seem to be four problems 

 with this measure, however. First, the appropriate variable, standing as a 

 proxy for prospective angler bag, may be a complicated, but is certainly an 

 unknown, combination of the several possible measures; number of fish, average 

 size; and number of very large fish. Second, the measurement and prediction of 

 any indicator of bag raises a difficult question of simultaneity, for participation 

 and bag are probably connected through the sustainable yield function for a 

 species (or group of species) as well as through the participation equation 

 reflecting human decisions. Third, with so many important species highly 

 migratory in habit, tracing any pollution effects on a size variable would 

 require tracing migration routes and understanding effects that may involve 

 only one stage of a fish's life cycle. Fourth, even for resident fishes, the 

 effect of some kinds of pollution, especially that involving nutrients and 

 organic carbon, may be ambiguous. (See, for example, Chittenden 1971, 1976; 

 Roberts et al. 1975; Wise 1974; McHugh 1972, 1975; Hedgpeth 1966; Pararas- 

 Carayannis 1973; Carlisle 1969; Brown and Beck 1972; Bascom et al . 1979; Soule 

 and Oguri 1979; National Marine Fisheries Service 1972; Butler et al. 1972; 

 Smith 1973.) 



A third possibility might be thought of as an amalgam of the first two — 

 some index of ecosystem health, reflecting species types present and abundance, 

 and indicating the overall quality of the available experience. (See, for 

 example, Hillman et al. 1977, McErlean et al. 1972, Bader et al. 1970, Bechtel 

 and Copeland 1970, Haedrich 1975, Livingstone 1975.) 



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