378 
terraces. The escarpments had in general an 
abundant fauna of fishes and invertebrates. 
Areas of some of the terraces have a scattered 
covering of rubble with attached algae as deep 
as 90 meters. Algae also were noted on the 
escarpment areas. Where the escarpment was 
deeper than 90 meters it appeared to lack algal 
growth and had a poorer epifauna as compared 
with the escarpments in shallower water. At all 
depths, in holes and small caves, an abundant 
fauna was noted of fishes and invertebrates 
characteristic of their environment. 
RECONNAISSANCE TECHNIQUES 
(( Asherah” Operations 
To obtain the maximum amount and the 
highest quality of scientific data during the 
investigations it was felt that, simultaneously 
with the use of the "Asherah,” other techniques 
should be employed to measure biologic and 
geologic parameters. Consequently, while the 
"Asherah” was diving, the "Teritu” was en- 
gaged in bathymetric or photographic surveys 
or geologic and biologic dredging operations in 
the same general area. (For equipment specifi- 
cations see the appendix.) 
The "Asherah” was moored each night along- 
side the "Teritu” off Makua Valley. During the 
night her batteries and compressed air tanks 
were recharged. The daily procedure was to take 
the "Asherah” in tow with a 1 6-foot power 
boat early each morning and proceed to the 
proposed diving locality. Upon reaching the 
diving site the "Asherah” was released, made 
ready for diving, and boarded. Each dive lasted 
for from 2 to 3 hours and generally two dives 
were made a day. During the time the 
"Asherah” was actually under water she was 
accompanied on the surface by a 13-foot power 
boat with which she maintained direct and con- 
tinual communications. From November 1 
through November 5, 15 dives were made. 
Remotely Controlled Stereo-Photography 
While the "Asherah” and her accompanying 
small boats were actually engaged in diving 
operations, the "Teritu” was also employed in 
data collection. Each area transversed under- 
water by the "Asherah,” as well as additional 
interesting areas, were photographed from the 
PACIFIC SCIENCE, Vol. XXII, July 1968 || 
surface by the "Teritu.” Edgerton, Germeshan- 
sen and Grier cameras were used, depth-con- 
trolled by a pinger unit mounted on the camera 
frame and monitored by the Precision Echo 
Sonic Recorder aboard the "Teritu.” A stereo- 
double-) camera arrangement was employed, 
and both black and white and color film were 
used. In all, 500 pairs of photographs were 
taken at depths of 120 to 300 meters. 
Echo Sounding 
Numerous continuous echo sounding profiles 
were made by the "Teritu” prior to, during, and 
subsequent to the "Asherah” dives. The equip- 
ment used consisted of an EDO echo sounder 
towed outboard in a Braincon streamlined 
housing and a gif ft recorder (Precision Echo 
Sonic Recorder). Because of the high degree 
of sensitivity of the recording unit, it was 
possible to record fish schools and micro-relief 
on the various submerged terraces, and conse- 
quently the echo sounding profiles were instru- 
mental in determining the diving localities for 
the "Asherah.” Twenty of the best echo sound- 
ing profiles are shown in Figures 3a-3d, their 
localities in Figure 1 ; these records form the 
basis for the bathymetric chart shown in Figure 
4. Three of the echo sounding profiles (Nos. 4, 
10, and 11) show excellent examples of fish 
populations, and consequently are reproduced 
in Figures 5, 6, and 7. 
Geologic Dredging 
Numerous attempts to dredge rock from the 
various marine terraces and escarpments were 
made by the "Teritu.” Heavy pipe dredges with 
chain bridles were used connected to the ship 
by %-inch steel wire, but the light "A” frame 
and sheeving system of the "Teritu” prevented 
heavy strains being put on the system. Dredging 
on the outer edge of the Penguin Banks Shelf, 
just north of Kepuhi Point, recovered reef rock 
fragments with freshly broken surfaces. These 
samples came from depths of from 50 to 60 
meters and probably represent the outcrops 
marking the boundary between the Penguin 
Banks and Mamala shelves. Similar reef rock 
fragments were obtained at depths of 120 
meters on the Mamala Shelf off Makua Valley. 
Attempts to break rock off the major escarp- 
ment between the Mamala and Lualualei shelves 
