5 . 
--■- ‘bie climate, "winter-kill "(?) or a latitudinal shiit 01 seme: xind. 
T v. 7 , post-winter decrease of grid birds does not happen to be as 
shorn as the post-summer decrease. In the spring ana early summer 
adults may be"increasing in peripheral areas after breeding, nest 
-Ivlure, during long distance foraging, chick abandonment, etc. Tnese 
cost and non-breeding adults together with whatever remains of the 
winter non-breeding peak form the summer high. Aside from the^ 
intuitive simplicity of this pattern there is little evidence to 
sunoort it over an alternative hypothesis such as correlation, widi 
surface temperature or any other ecological parameter. Two pieces 
of isolated information do however support the age dependant cycj_e 
idea. During EGS #5 in early April, Harrington notes tha^ special 
attention was given to recording the numoer oi white-rumped vP re ~ _ 
sumed to be adult) birds, and that only one such white-rumped. otrd 
was seen. Fifty-four birds were recorded during that survey ocu 
there is no reference to how many of these were actually checked. 
In late July-early August on EGS #10 15 white-rumped birds were. . 
recorded among 42 actually checked (32 percent;. Further investigation 
of rump color ratios is needed. Little attention was given tu rump 
color during the present cruise but my feeling is that there were few 
(less than one-fifth?) white-rumped individuals. The survey-to-^ 
survey distribution of albatross within the grid is on the whole too 
small" statistically to infer much. In general though it appears 
that the pattern of high density in the northeast and low density 
the southwest corner holds true when the overall grid density 
** VV 
_ 
o' UI. Kjj. u Vy v ^ 
trosses) is non undergoing a marked change. When rapid 
- b 7 q ___ ____ 
^ate of change is occurring the pattern becomes confused or shixos 
to the southwest as in EGS #1. At any rate the static conditions 
a-spear to bring the maximum density close to the coast in the north- 
■c;ast) corner ci "the grid. 
Sooty Shearwater ( Puffinus griseus ) 
# Obs. = 113. 
High numbers were moving across the grid along a. southwest 
"-'re which atuears to lead from Point Conception rougnly toward 
Christmas Island of the Line Island Chain. This survey’s_data nave 
been lumped with the data for EGS # lk and are discussed in more 
detail there. 
= 2 . 
Pink-footed Shearwater ( Puffinus creatopusp jf Oos 
Pink-foot is."by no means a regular grid bird; preferring mo.*.e 
stal waters and being regularly seen around the Channel Islands. 
Zt is however often associated with Sooty Shearwater flocks and 
should be expected wherever sooties are common. One bird was^seen 
an each of the two days that sooties were most abundant ybcCbiu^ 
a and 8";. 
cca 
