PRELIMINARY REPORT 
Eastern Area Cruise #18 
3 Aug to 25 Sept I 967 
ITENERARY 
3 August 1967 
21 August u 
23 August " 
26-27 August 
- Depart San Diego 
- Reach 10 °S, 119 °W 
- Reach 10 °S, 112 °W 
- Depart cruise track for rendezvous with 
r/v undaiwed 
29 August to - Special current study along 112°W.at equator 
2 September 
II September - Arrive Manzanillo, Mexico 
13 September - Depart Manzanillo, Mexico 
19-23 September-Special study at south end of Guadalupe Island 
25 September - Arrive San Diego 
This report summarizes observations made by T. James Lewis on 
E4STR0PAC cruise August 3 to September 25 aboard the Scripps 
Institution of Oceanography Research Vessel THOMAS WASHINGTON. The 
ship departed San Diego August 3 (see FIGURE l), proceeded to 20°N, 
119then south to 10 °S, then east to 112 °W, then north to the 
equator, with a short diversion eastward near 3 °S to rendezvous with 
the other EASTROPAC vessel, R/V UNDAUNTED. After a 5-hay current 
study near the equator, the ship proceeded north again along 112°W 
to 12°N, and then northeastward to Manzanillo, Mexico. After two 
days in Manzanillo, the cruise continued westward and northwestward 
to Guadalupe Island for a 5-day study, and then directly to San 
Diego, arriving early in the morning of September 25- Observations 
of birds, mammals, and turtles^ made on 4-5 days of the trip, are 
presented in TABLES 1-12 and FIGURES 1-9 at the end of this report. 
A total of 8,68l birds of L5 species were observed between sunrise 
and sunset. An additional 205 birds of 9 species were seen at 
night. Juan Fernandez Petrels, Sooty Terns and Wedge-tailed Shear¬ 
waters were the dominant birds in two rather small areas between 5°N 
and 7°N (FIGURE 3)- Diurnal observations were conducted for 298.6 
hours during which the ship traveled ^ y 0k0 miles. Nocturnal observa¬ 
tions were conducted for 3^*5 hours while the ship was underway. 
Excellent cooperation was received from the captain and crew 
as well as from many of the scientific party. Use of the skiff on 
several occasions would not have been possible without their help. 
