TABLE l4. Summary of North Pelagic Sections Relative Linear Densities 
N of "12°N" M 12 0 N" 12 _"5°N 
GrOUU 
Albatross 
Shearwater 
Pterodroma 
' ♦ 
Total Shear/Pet. 
Storm Petrel 
Tropicbird 
3ooby 
Frigate 
Tern 
All birds 
0,, rr°T\r n ' T cT ° i\T * 1 
S o 
-O ,, c'°t v t ,t 
1 
1 
1 
1 
1 
10 
4 
7 
2 
0 
1 
17 
3 
1 
9 
7 
0 
7 
0 
1 
10 
2 
2 
1 
1 
0 
0 
10 
9 
11 
4 
1 
2 
1 
8 
o 
l 
2 
■3 
0 
1 
0 
l4 
10 
1 
17 
14 
Note; The values -"V"- in each line are determined by: 
V = (Lin. Dens, x A) - 3 
Where A and B are arbitrary numbers chosen such that V is 
a small positive integer and the V for the section with 
the lowest linear density is 1. 
Each bird group is mostly found in the section or sections 
with the larger or largest relative number(s). Plotting 
the values in Table l4 gives a similar graph to that obtained 
by plotting the corresponding linear densities, except there 
is no base line and no fixed scale on the abscissa. 
B; 
.uhythermo graph Data 
(Numbers in parentheses refer to numbered grapns. 
Letters refer to specific features oi the grapn). 
While 3T casts were routinely taken over almost all the area ox oo-^ 
servation in the north pelagic section, only selected portions of the data 
are presently available for discussion. 
Tbe major measurable features oi a bi orace are. 
1) Surface temperature (not often directly used)• 
2) Temperature at any depth. 
3) The depth of any given temperature. 
4) Depth of isothermal mixing. 
5) Depth of greatest rate of change of temperature Vi.m 
depth-thermocline. 
