At the mouth of the Gulf of California no oceanographic data were 
collected. However, as the Gulf was approached from the southeast a 
distinct current line was crossed. This suggests that the vessel was 
entering a different water-type, which is a logical presumption in light 
of the known oceanography. 
Off Cape San Lucas another water type was probably present, but no 
signs of a division were observed by the writer beyond slim suggestion by 
bird distribution. 
The last major area of water being considered is that in the southern 
extremes of the survey area south of the North Equatorial Countercurrent. 
The water was characterized by high salinities and low temperatures and 
was probably the northern portion of the westward flowing South Equator¬ 
ial Current. 
One other portion of the survey area will be considered as another 
water type although insufficient oceanographic data were collected to 
justify such a separation. However, on the basis of bird distribution 
such a division seems reasonable. Thus the section of the western leg of 
the cruise between 15° and 28°N will be treated as a separate water type. 
As mentioned above, the oceanographic characters of a water type are 
either directly or indirectly major factors in delineating species and 
density distribution of birds. Whether this holds true for migrants as 
well as resident birds will not be a concern in this report as there was 
little suggestion of migratory travel throughout the cruise. Thus it is 
felt that a correlation of distributions and water types would reflect 
the uninfluenced effect that water types have on the presumed resident 
birds. The divisions as established in the above discussions are shown 
in map 2; maps 3 and ^ show surface temperatures and salinities for 
additional reference, and table 2 shows the species breakdown for each 
area. Table 3 shows species habitat (water type) preference in a simp¬ 
lified form. 
SPECIES ACCOUNTS 
(Note: Only species for which there is additional information are listed 
below. See Tables for total avifauna.) 
Procellaria sp . 
A single bird which was probably a Black Petrel ( Procellaria park - 
insoni ) "...bird all dark, light-colored bill (which was fairly short); 
body shape much like an albatross, wings shaped like an albatross. 
Flight was very distinctive,...frequent twisting and turning, a rapid 
flight; smaller than a Black-footed Albatross, but (slightly) larger 
than a Pink-footed Shearwater; tail was quite short." An accompanying 
drawing of the underwing shows that it was all dark with a lighter area 
on the ventral tip. 
