Marine Fungi from Central Pacific — Steele 
tions do exist in this environment, but that 
frequencies vary with zones. The oceanic zone 
had fewer isolates than did the other zones 
studied in the pelagic region. This result was 
expected, inasmuch as oceanic regions are 
known to have lower populations of marine 
organisms than do regions closer to land. Of 
the 59 water samples, 50 were taken from areas 
that are strongly influenced by the presence of 
oceanic islands, whereas the other 9 were from 
areas well away from any shore. Areas near 
islands are known to support abundant and 
varied marine life. Ships may also be a source 
of water pollution, and therefore modified 
populations might be expected in shipping 
lanes. 
Differences can also be observed between 
the two oceanic locations studied, as reflected 
in differences in kind of fungi present but 
not in numbers. The oceanic area off Johnston 
Island contained more yeasts than did surface 
samples obtained near the island of Oahu. 
The latter had more fungi which would be 
classified as terrestrial, such as aspergilli and 
penicillia. The high yeast population observed 
from the oceanic areas is in agreement with 
the findings of both ZoBell (1946) and of 
Fell and Van Uden (1963). Members of the 
genus Rhodotorula were isolated consistently 
from all water samples, including the depth 
samples. Roth et ah (1962) have noted the 
common occurrence of these yeasts in oceanic 
localities, an observation now confirmed by 
these studies for the Pacific Ocean. 
When the three zones — surf, inshore neritic, 
and offshore neritic — are compared, a correla- 
tion is found between numbers of isolates per 
ml and location of zone. This is not unex- 
pected. This correlation is particularly clear in 
the data for these zones in Oahu. The surf 
zone, which is an unstable area with constant 
wave action, returned 0.10 isolates per ml com- 
pared with 0.33 for offshore neritic and 0.83 
for inshore neritic zones. Species of Curvularia, 
Alternaria, and Helminth osporium were iso- 
lated repeatedly from the inshore neritic zone. 
This zone, in the area of Oahu, is richer in 
number of species than is the same zone on 
Hawaii. This might be due to pollution, as 
Oahu has a greater population and has a major 
port for shipping. Members of the order 
327 
Sphaeropsidales, of the Fungi Imperfecti, were 
frequently found in the Oahu samples. These 
fungi are parasitic on plants. The polluted 
area contained much floating debris which 
could serve as a source of these fungi. 
Some water samples were taken from tidal 
pools in the intertidal zone. In every case there 
was a high number of isolates. Intertidal pool 
populations may be affected by higher temper- 
atures, higher organic content, salinity levels, 
or wave action. One area, however, that of a 
large bay on the windward side of Oahu, did 
not return a high yield of isolates. This area 
has a high fresh-water run-off which reduces 
the salinity at the surface as much as 5 %o dur- 
ing the rainy season. Even though the area 
had a lower population than expected, it did 
have great diversity, explained perhaps by the 
run-off factor. The high number of aspergilli 
and penicillia isolated was to be expected 
because of their proclivity for sporalation, 
cosmopolitan habitat, and their great adapt- 
ability. A good percentage of these might be 
run-off and/or air contaminants introduced into 
the water. 
The fact that more fungi were isolated from 
the sand than from the water supports the 
well-known observation that microbial popu- 
lations are higher in relation to fixed surfaces. 
Examination of Table 3 also shows that the 
general population of sand is quite different 
than that of water. 
The high number of isolates from the sand 
samples taken from the leeward Hawaiian 
islands and the few species among them is in 
direct contrast with the low number of isolates 
and high number of species in the samples 
from the Phoenix Islands and the Line Islands. 
There could be many reasons for this. The 
elapsed time before plating the leeward sam- 
ples was greater than for those of the Phoenix 
and Line islands. Variations in bird population, 
temperature, and humidity, and shore stability 
among the leeward Hawaiian islands, may be 
critical factors controlling fungus populations. 
If the bird population serves as a control, a 
survey for keratinophilic and coprophilous spe- 
cies might be rewarding. Such a survey should 
also extend to other islands with large bird 
populations. Another factor influencing fungus 
populations, as reflected in the high number 
