Eastern Area Cruise #27 
l6-26 October 1967 
including 
Eastern Grid Survey #15 
Cruise Itinerary: l6 October 0800 
17 October 0300 
25 October 2115 
26 October 1800 
Depart Alameda 
Enter Grid at Point "Ash" 
Depart Grid at 35°00’ N, 122° 38 ’ W 
Arrive San Francisco 
Survey Personnel: Richard Chandler (Biologist-in-Charge) 
Robert L. Pyle 
Thomas J. Lewis 
Methods 
Diurnal observations were held from the helicopter deck on the l 6 th 
through l 8 th. The watch was moved to the lee wing of the bridge from the 
19 th onward due chiefly to strong winds. Two periods of nocturnal watch 
were held at the searchlight on the port (lee) quarterdeck. The skiff 
was used for l-l/2 hours on 17 October, but collecting conditions were not 
favorable again during the remainder of the cruise. No birds were 
secured from the skiff, but several errant landbirds were shot as they 
rested on the deck. Bathythermograph soundings were made at 2-hour 
intervals from 0400-2000 and at 2400 while in the Grid area. The BT 
instrument was lost overboard on 25 October at 23^-5 • Other methods and 
procedures followed those established on previous cruises-. 
Cruise Track (See Figure #1) 
The two non-Grid legs between San Francisco and the Grid are over 
essentially the same area and save for the influence of weather are roughly 
comparable. (See non-Grid discussion.) The nominal Grid track was 
covered, with little deviation from Point "Ash" to a point about 70 miles 
west of Point Oak. At this point, sunset of the 24th, it was prudent to 
turn north in order to make best use of the diurnal hours in the two 
sections "T" and "W" which needed the additional coverage. The 900 
diurnal Grid miles were divided among the nine sections fairly equally 
(average deviation from 100 miles sabout 11 miles; see Table #2). 
Excellent cooperation was received from Captain Reiser, the deck 
force, weather personnel, quartermasters, and all concerned with the 
operation. 
Conditions 
During most of the survey period a moderate high pressure system to 
the west of the Grid and a trough of low pressure over the southern 
California area produced a gradient that resulted in moderately strong 
(20+ Kt.) northwest winds. Seas and winds were low on the 17 th beiore the 
