8. Differences were noted in community structure on the south versus 
north jetty. These differences are partly attributed to differences 
in duration of rock submersion, season of rock placement at the study 
sites, and water depth. 
9. Strong vertical gradients were detected in the distribution of 
most dominant sessile species. Barnacles and blue-green algae were 
common only in the intertidal zone. Mussels were most abundant from 
+0.5 mto-1m. Green algae were abundant at MLW and shallow subtidal 
depths (-1 m), whereas red algae were common at those levels and at 
deeper depths (-2 m). Hydroids, bryozoans, and ascidians were generally 
restricted to subtidal areas, but in that zone less pronounced vertical 
gradients were observed for species in those taxa. 
10. Motile macroinvertebrate species quickly colonized the rocks, with 
abundances as high in the first year as in subsequent years. Generally, 
individuals of motile species were more widely distributed among levels 
than noted for the sessile species, although some were limited to the 
intertidal or subtidal zone only. The abundance and species richness 
of motile fauna usually increased at the lower levels sampled, and in 
both zones, the dominant species were generally amphipods or isopods. 
Differences were noted between years with respect to overall community 
structure, but these differences were less than those observed for the 
sessile community. 
1l. Fishes appeared to be quickly attracted to the rocks and were present 
in high numbers one year after construction of the north jetty. Community 
composition of the fishes included many recreationally important species, 
such as black sea bass, sheepshead, spadefish and flounder. Analysis 
of fish stomach contents indicated that jetty fauna and flora were primary 
food items for sea bass, sheepshead, spadefish, grunt and tautog. 
Additionally, it appeared that these fishes minimized competition for 
food through differences in their primary diet component. 
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