3.4 Biological Resources
Surveys for nearshore reefs were conducted in areas where the model indicated the potential for more
persistent sand deposition and where resources had not been mapped or where mapping identified hard
substrate, but that substrate was unquantified or uncharacterized. Surveys also validated data from various
sources including prior mapping performed by the Navy and information from commercial fisherman (at
selected locations). These surveys were conducted January 18 through 25, 2000. The purpose of these
surveys was to quantify the hard substrate, determine relief heights of the hard substrate, and determine the
presence or absence of reef indicator species. The indicator species were selected in consultation with the
resource and regulatory agencies to be consistent with the U.S. Navy's previous resource mapping for the
project. The indicator species included surfgrass (Phyllospadix spp.), giant kelp (Macrocystis pyrifera),
feather boa kelp (Egregia menziesii), sea palms (Eisenia arborea), and sea fans (Muricea spp.). All of
these species are perennial, although feather boa kelp oc cur in locations where scour and other ocean
process result in high (yearly or less) morbidity. Feather boa are extremely quick to recolonize.
Additionally, the occurrence of non-vegetated hard substrate or substrate vegetated only with opportunistic
coralline algal turf was noted. The relative abundance of indicator species was noted as abundant,
common, or sparse similar to that for the receiver site surveys.
Hard substrate on nearshore reefs in intertidal and shallow, inshore areas were assessed by walking the
beach during extreme minus tides (-1.4 to -2.1 MLLW) between January 18 and 20, 2000. Next, subtidal
hard substrates were mapped according to location and relief height using side-scan sonar from January
22 to 25, 2000. Following the side-scan sonar work, biologists using S.C.U.B.A. dove on the sonar-
identified hard substrates and noted reef heights and presence ofindicator species and/or coralline algalturf.
Divers swam transects to complete map coverage between side-scan sonar and minus tide survey limits.
They also swam transects to map an area off Solana Beach where kelp canopy cover had interferred with
operation of the side-scan sonar. Divers deployed buoys to mark reef edges and dramatic changes in
resource development (e.g., surfgrass versus non-surfgrass areas), and DGPS readings of the buoy
locations were recorded. The dives were conducted from January to March 2000. Maps were prepared
of the surveyed areas that included the extent of all hard substrate within the survey area, relief heights, and
the recorded biological notes. The dimensions of the hard substrate areas were measured to provide
acreage according to biological resource categories.
Borrow Site Surveys
Offshore surveys were conducted at proposed borrow sites S0-7 and SO-5 to obtain representative
information on the offshore habitats. To assist in the evaluation of potential borrow site impacts, a survey
Regional Beach Sand Project EIR/EA
Page 3.4-3
99-69\SANDAG EIREA 3.4.wpd 7/17/00
Previous Page
