EFFECTS OF PULP MILL POLLUTION ON OYSTERS 
175 
been found unnecessary. Since these pieces of apparatus do not leave the oyster 
beds, these facts indicate that abnormal conditions exist in the water over the 
oyster beds. 
Barnacles, mussels, and hydroids normally found on floating euqipment used 
about the oyster beds are not noticeably affected by normal fluctuations in the 
physical factors in the environment. They are found where the salinity is higher or 
lower than that ever found in Oakland Bay. They occur to the north and to the 
south and thrive in water which is both warmer and colder than near the oyster beds. 
We can assume, therefore, that fluctuations in temperature and salinity do not account 
for their absence from the floating equipment referred to; domestic sewage does not 
appear to affect these organisms seriously, and one looks upon the annual crop as a 
matter of course. Their absence, therefore, from the oyster beds indicates that 
abnormal factors, other than temperature, salinity, or sewage, must be considered in 
relation to the condition in Oakland Bay at the present time. 
PLANT GROWTH 
It is evident that the growth of some plants was stimulated by the conditions 
existing in Oakland Bay during the winter of 1928-29, and the spring and summer 
of 1929. The chain diatom Melosira borreri, Greville, grow in dense masses over some 
sections of the oyster beds. Where the current was slow over beds that were between 
2 and 4 feet above the lowest oyster dikes, it formed a mat that completely covered 
the oysters and shells. This diatom is present at all times in small amounts on 
oyster beds of the same level in near-by bays, but it is evident that the growth was 
greatly stimulated in this particular place. 
The distribution of this plant growth apparently bore no relation to the mortality 
of the oysters. Many beds were free from it, and had a high death rate of oysters. 
The lower grounds, which suffered the most in the recent disturbance, were not 
affected by Melosira at all. Some beds that were covered with a heavy mat experi- 
enced almost a total loss of oysters, while others showed nothing abnormal. 
It is concluded, therefore, that Melosira does not injure the oysters, but, that its 
dense growth indicates a disturbed condition of the water in which it normally grows 
in small amounts. 
POSSIBLE EFFECTS OF LOG STORAGE 
The effect of logging operations and sawmill waste upon oysters is a much debated 
question. In Oakland Bay sawdust is absent, and can not be considered as affecting 
the oysters. There are, however, at all times, many log booms in the bay, and they 
have been blamed for oyster mortality. Certain chemicals in the logs are supposed 
to pass into solution and to affect the oysters. In Eld Inlet the log storage is pro- 
portionally greater than in Oakland Bay; new logs are constantly being added and 
any chemicals that leach out of the timber would be in high concentration in this 
place. However, the water is normal in color and the oysters which live in the bay 
prove that no harmful chemicals are present. In coves and lagoons where the 
bottom is covered with decaying vegetation and many tree trunks are strewn about, 
one would expect the wood chemicals in solution to be at a maximum. Such places 
are known to produce a natural set of oysters which grow and mature normally. 
Nothing about their condition suggests any effect of wood chemicals. 
The oyster larva will set upon pieces of hemlock bark recently stripped from a 
tree. In this case the oyster comes in direct contact with the phloem tissue which 
