6. Peaks in the base ambient noise level at 2000 and 
0400 hours in the 160 c/s to 1000 c/s range at the shallow 
hydrophone were mainly the result of increased activity of 
the Click Chorus. 
RECOMMENDATION 
Conduct further studies at the same locations 
during the same month of the year using additional equip- 
ment to obtaindirectional sound information and under- 
water visual information, in order to determine the sources 
of the sounds in the area. 
ADMINISTRATIVE INFORMATION 
The work was assigned by BUSHIPS letter 688-057 of 
9 Dec 1960 and was performed under SF 001 03 16, Task 
8529 (NEL E11351) during the period January 1964 through 
December 1964. The report was approved for publication 
24 May 1965. 
Acknowledgment is due G. M. Wenz, for general 
consultation and for furnishing the tape recordings and 
3 -octave-band strip-chart records for this study. The 
author is also indebted to G. M. Wenz, M. A. Calderon, 
and T. F. Scanlan for the field data and other information 
in NEL Report 1260 which were helpful in writing this 
report. The field work described in NEL Report 1260 was 
accomplished under SR 004 03 01, Task 8119 (NEL L20451). 
