In comparing the; fauna (only polychaetes, mollusks, and crustaceans) the 

 qualitative similarity (Jaccard's coefficient) is 0.67, which is a moderate 

 similarity for the overall fauna. If the comparison is made by a major 

 taxonomic group, then the similarity between studies is 0.88 for polychaetes, 

 0.33 for mollusks, and 0.64 for crustaceans. The polychaetes are very 

 similar between studies with two taxa occurring in 1976 that did not occur 

 in 1981, and one taxon in 1981 that was not found in 1976. The only mollusk 

 in common was Donax spp., with two other species occurring in 1976 that did 

 not occur in 1981, and vice versa. The crustacean fauna had seven species 

 in common and four that occurred in one study, but not the other. The 

 overall number of species was 22 for 1976 and 21 for 1981. If only the 

 four top dominant taxa are compared, they are identical between studies 

 {Emerita talpoida , Donax spp., Scolelepis squamata , and haustorids) . 

 Species differences between the studies occur only in the uncommon species 

 (Table 27) . 



In 1976, the Emerita talpoida remained in the swash zone throughout the 

 study because the temperatures on all four collection dates were always above 

 10° Celsius. In 1981 the temperature in January was low, 5° Celsius, and the 

 Emerita talpoida left the swash zone. Densities of this decapod were lower 

 in November 1975 than in 1980, but well within the range described by Diaz 

 (1980) and Bowman (1982) for yearly variation. In the other comparable 

 collections (April to July) densities were surprisingly similar between 

 1976 and 1981. 



In 1976, the Scolelepis squamata was more common, occurring at more than 

 70 percent of all collecting sites. In 1981 it occurred at 62 percent of the 

 sites. Densities in 1976 were comparable to those in 1981, being slightly 

 higher overall from April to July 1976. The November collections were 

 similar, averaging 86 worms per square meter in 1976 and 74 worms per 

 square meter in 1981. Scolelepis squamata occurred in and near the swash 

 zone commonly in June to July 1976. In July 1981, when it was most abundant, 

 it had one occurrence in the swash zone. 



In 1976, Donax spp. was widely distributed in June and July with 

 occurrences in and near the swash zone. In July 1981, Donax spp. was 

 virtually absent. In November 1975, there were few occurrences of Donax 

 spp., all being found farther offshore. In November 1980 it was common, 

 but only offshore. From the dynamic nature of this species populations 

 (Mikkelsen, 1981) the differences between 1976 and 1981 are not outside 

 the range of variation usually found in beach populations. 



The haustorid amphipods (Parahaustorius longimerus in Matta, 1977) were 

 distributed similarly in 1976 and 1981, with there being slightly higher 

 densities in 1976. After comparing the four dominant species, it seems 

 that the basic species distributions and abundances are similar or within 

 the ranges of variation reported in the literature. 



The species diversity (H ! ) for both studies was low, with a slightly 

 greater range in 1976 of 0.00 to 1 .85. In 1981, the range of diversity was 

 0.00 to 1.67. One distinct faunal community seemed to be present in both 



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