Preliminary Report - Southern Grid #1 6 - 16-22 April 1967 
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prepared by Richard D. Chandler 
Survey Personnel : Richard Chandler (BIC), Prank Smith, Dennis Stadel, 
F.C. Thompson, Robert Tuxson, Mike Scanlon, Vince Bass 
Support Vessels : USS GEORGE EASTMAN, Y-AG 39; LT 2086; LT 2087 . 
Itinerary: 
16 April 
• 
O 63 O 
16 April 
O 83 O 
17 April 
• 
0800 
17 April 
1200 
17 April 
" 1800 
18 April 
1600 
20 April 
0800 
22 April 
0800 
Begin Grid observations from YAG 39 
Transfer Tuxson from YAG 39 to LT 2086, 
Stadel & Scanlon to LT 2087* 
Tuxson & Bass land on Baker with LT 2086 
remaining offshore. 
♦ 
Stadel & Scanlon land on Howland with LT 2087 
remaining offshore. YAG departs for Grid 
observations Western half. 
Tuxson and Bass depart Baker 
Tuxson & Bass land on Howland 
Island personnel depart Howland for duplicate 
Grid observation aboard LT f s 
3 vessels rendezvous 5 miles N. of Howland 
Tuxson & Scanlon return to YAG 39* Stadel 
remains on LT 2087 for duplicate Grid ob¬ 
servation. 
A team of seven conducted a 6 -day survey of the Southern grid area, 
including a one day survey of Baker Island and a 3 -day survey of Howland 
Island (see separate reports). This report summarizes the at-sea ob¬ 
servations in the grid area from 16-22 April. This, the l 6 th and last 
survey of the current series departed from past cruises in that three 
support vessels were available simultaneously. This allowed for Improved 
coverage of the pelagic area; roughly a two-fold increase over most pre¬ 
vious surveys. Fifteen of the 16 square subdivisions were covered during 
diurnal hours with an average of 86 miles of observations per area® Over 
the 1,289 total diurnal miles 4,046 birds of 25 species were recorded. 
The overall linear density (birds/linear mile) of 3*1^ was roughly l/2 
the densities determined in surveys 14 and 15 (Jan. & Feb.) Sooty Terns 
accounted for 9^-»7 percent of all diurnal observations« Sooty Tern 
densities were high (above overall average) in southern areas, JKLMOo The 
Sooty Tern density for area G (Howland - Baker section) was below the over¬ 
all average quite unlike previous surveys. This reflects the marked 
"dispersion" from the breeding colony on Howland. The concentric circle 
densities also demonstrate that Sooty Terns were not localized around the 
Howland area: Area O- 3 O miles = 1•55 Area 30-60 = 3*5? Area 60-110 = 2.3J 
