quarterly intervals (August, November, February) during the first year 
after construction, and then at yearly intervals (July or August) through 
1982. 
3. Biological Sampling Methods 
Characterization of epibenthic communities was accomplished using 
three systematic sampling techniques: (1) line-transect census, (2) 
photographed-quadrat census, and (3) suction sampling of motile species. 
Data collected by the three sampling methods provided information on 
species composition, relative percent cover or abundance, and distri- 
bution. In addition, general collections and observations of species 
were made during all sampling periods. 
a. Line Transects 
Percent cover of the sessile biota was assessed at each level 
using a line-transect procedure modified from Loya and Slobodkin (1971), 
Porter (1972 a,b), and Loya (1972, 1978). For this assessment a clear 
plastic strip, marked at its edge with 15 points at 2.5-cm intervals, 
was placed against rock surfaces. All organisms occurring directly 
under each point were identified and recorded. Because different rock 
faces often displayed different densities or assemblages of organisms, 
assessments were made on each of the seaward, landward, outer, inner, 
and top surfaces of jetty quarrystone. The transect strip was always 
positioned horizontally on vertical surfaces, and data from the five 
rock faces were summed to provide an overall estimate of percent cover 
based on the 75 points at each level. An effort was made to place 
the plastic strip on the rock faces without reference to the attached 
biota to avoid sampling bias. If more than one species was present 
under a point, all were recorded and percent cover estimates for each 
species at a given level were based on the percentage of points it 
occupied. Because this procedure commonly resulted in estimates of 
total biota cover greater than 100%, total estimated biota cover was 
determined by substracting the estimated percent of unoccupied space 
from 100. Poor water visibility and waves precluded in situ assessment 
by line transect at the subtidal south jetty levels (only). Instead, 
rocks were removed from the appropriate depth at those stations and 
brought to the surface for examination. At all stations, organisms 
which could not be identified in the field were preserved and returned 
to the laboratory for identification. Samples of blue-green algae were 
also collected for laboratory identification, but species in this 
taxonomic group could not be identified in the field and all were 
identified only as Cyanophyta. 
b. Photographed Quadrats 
A photographic census was also conducted to obtain additional 
quantitative estimates of the jetty epibiota, and to provide a more 
permanent record of biota at each level. Color photographs were obtained 
of the same rock faces (i.e., seaward, landward, outer, inner, top) at 
all station levels using a Nikonos III camera with flash attachment. 
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