MARINE BIOLOGICAL SURVEY OF THE PROPOSED DOCK SITE ...

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3METHODSThe proposed dock site was visited from March 4 to 7, 1977.Four transects extending across the reef flat and down the slope tothe channel floor, were established in the study area (Figure 2).The biota was quantified for each 10-meter interval along each of thefour transects.Marine plants were quantified by haphazardly tossing a 25 cm x25 em gridded quadrat with sixteen interior "points" (intersectinggrid lines) five to ten times for each 10-meter transect interval.The percent cover or abundance was calculated by dividing the numberof points at which each species was recorded by the total number ofpoints (16 points x number of tosses) and multiplying by 100 toobtain a percent value.Reef corals were quantified by a point-quarter technique (Cottamet al, 1953). At stations 5 meters apart (i.e., two per 10-meterinterval along the transect), a point was selected somewhat randomlyby dropping a collecting chisel. The orientation of the chisel wasused to define perpendicular axes. Within each of the four quadrantsdelimited by these axes, the coral nearest the intersection point waslocated, and the species name, the diameter or basal area of thecoral and the distance from the center of the coral to the point wererecorded. By combining the data for all points falling within eachof the various reef zones (see below), the percentage of substratecovered and the frequency of occurrence for each species encounteredwithin a given zone was calculated. An importance value (IV) foreach species was determined by summing the relative value of thesetwo parameters. Overal density and percentage of substrate coveredby living corals were also determined for each reef zone.Large echinoderms and other macro-invertebrates which occurredwithin one meter of the transect line were enumerated for each 10-meter interval. A separate enumeration was made for the left sideand the right side of the line in order that two censuses, eachcovering an area of 10 m 2 , could be made for each 10-meter interval.All fishes observed within one meter of either side of thetransect line were recorded for each 10-meter interval.Qualitative surveys of marine plants, corals, macro-invertebrates,and fishes in the study area and in an area on the opposite side ofthe channel (Figure 3) were also made so that more complete specieslists could be compiled for the study site, and so that generalcomparisons could be made between the study site and the area acrossthe channel.
4HIGH TIDE HIGH TIDE0LOW TIDELOW TIDE2· BOULDER BOULDER ENHALUS-RUBBLE RUBBLE THALASSIA SAND4 ZONE LAGOON ZONE ZONE ANDSAND SLOPE CORAL6 020J AND ZONE36 CORAL)0 24 6ZONE8 ENHAWS-THALASSIA10 ZONE 50-t10012TRANSECT 2SLOPE14TRANSECT 11618HIGH TIDE0BOULDERLOW TIDERUBBLE!:NHALUS-2ZONE THALASSIA SAND ANDZONECORAL ZONE40 36672TRANSECT 311 8LAGOONSLOPE 10014LOW TIDE2BOULDER 16RUBBLE4 ZONE ENHALUS- THALASSIA ZONE SAND AND18CORAi. ZOi:E61280 30 9510 12512 TRANSECT 414LAGOONSLOPE16182022Figure 2.Depth profiles of the four transects showing boundaries ofzones. Depth scale is in meters. Numbers at zone boundariesindicate distances along transect line. Vertical exaggerationXS.
Page 1 and 2: MARINE BIOLOGICAL SURVEYOF THE PROP
Page 3: 2I\.).. .......i I '.:'·1'., .....
Page 7 and 8: 6In order to assess the general pat
Page 9 and 10: -L8Table 1.Continued.SpeciesBoulder
Page 11 and 12: -10sandy substratum. The genus ~oly
Page 13 and 14: •12The outermost part of the reef
Page 15 and 16: 14To get some kind of idea what the
Page 17 and 18: 14To get some kind of idea what the
Page 19 and 20: 16Table 5 . Number of echinodenns p
Page 21 and 22: 18TRANSECT 1NumberofSpecies"lumbero
Page 23 and 24: -20Table 6.Continued.Boulder Enhalu
Page 25: 22CONCLUSIONS AND RECOMMENDATIONSCl

MARINE BIOLOGICAL SURVEY OF THE PROPOSED DOCK SITE ...

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