43 
Group 
Albatross 
Shearwater 
Pterodroma 
Bulwer Petrel 
Total Shearwater/Petrel 
Storm Petrel 
Tropicbird 
Booby 
Frigate 
Soouy Tern 
Common Noddy 
White Tern 
Miscellaneous 
Total 
Species contributing 1 percent 
Sooty Tern 
Wedge-tailed Shearwater 
Pterodroma^externa 
Bulwer Petrel 
Sooty/Slender-billed Sh. 
White-tailed Tropicbird 
Red-footed Booby 
Blue-faced Booby 
Storm Petrel (Leach) 
Jaeger 
io of N. 
Number 
Pelagic Bird; 
10 
0.3 
1122 
30.8 
249 
6.8 
65 
1.8 
( 1525 ) 
(4l.8) 
44 
1.2 
62 
1.7 
126 
3.5 
12 
0.3 
1748 
47.9 
13 
0.3 
12 
0.3 
102 
2.8 
3654 •• 100 
or more to the north pelagic total 
^ 7.9 ) .x 
28.2 ) w 0 * 1 ) 
4.0 
1.8 
1.8 
1.8 
1.6 
1.5 
1.2 
1.2 
91.05o 
During the four-month period of survey work almost half of the non-Grid 
diurnal miles of observation were spent in this region. Over 3600 birds of at 
least 29 species have been recorded over the 2923 diurnal miles. An addi¬ 
tional 96 birds of 5 species have been logged during 323 nocturnal miles. 
The large amount of data compiled is noteworthy in itself, but addi¬ 
tional factors make this a region of extremely high interest, l) The same 
route has been traversed quite regularly and consistently for a full year, 
and somewhat less consistently for several years. 2) The region is,for 
the most part, distant enough from land so that there is little influence 
from strongly land-based birds. 3) The nearest islands on all sides have 
been periodically surveyed by POBSP personnel so that observations at sea 
can be correlated with surrounding island populations which influence the 
regions avifaunal composition. 4) Oceanographic conditions have been system 
actically recorded by bathythermograph soundings since late 1965* 
The north pelagic bird data are analysed here as a function of two 
factors, latitude and oceanographic features as measured by bathythemo- 
grams. In the following discussion I will attempt to show various aspects 
I 
