OXYGEN CONSUMPTION OF NORMAL AND GREEN OYSTERS 1 
J, 
By 
PAUL S. GALTSOFF, Ph. D., In Charge, Oyster Fishery Investigations 
and 
DOROTHY V. WHIPPLE, M. D., Temporary Assistant 
CONTENTS 
Page 
Introduction 489 
Method 490 
Oxygen consumption of normal oyster 493 
Effect of oxygen tension on oxygen con- 
sumption 496 
Page 
Increased rate of metabolism 501 
Experiments with green oysters 502 
Oxygen consumption of green oysters 504 
Summary 506 
Bibliography 507 
INTRODUCTION 
The knowledge of the oxygen requirements of any bottom organism is essential 
in understanding the factors that control its distribution, growth, and adaptability 
to various local conditions. The purpose of the present investigation is to determine 
the rate of oxygen consumption of normal and green oysters and to evaluate some of 
the factors that govern the respiration of the lamellibranch mollusks. 
The respiratory exchange of the oyster has been studied by Mitchell (1914), 
who found that at temperatures between 19° and 28° C. oysters of medium sizes 
used from 0.7 to 3.5 milligrams of oxygen per hour per 100 grams of entire weight 
(from 0.35 to 1.29 milligrams per hour per 1 gram of dried weight), and that they 
showed considerable resistance to lack of oxygen. He noticed also that the oxygen 
consumption was exceedingly variable, depending on a variety of conditions which, 
he thought, affected the opening and closing of the shell. No attempts were made, 
however, to eliminate or control these variables. 
Nozawa (1929) in a study of normal and abnormal respiration of Ostrea circum- 
pida arrived at the conclusions that “the rate of the oxygen consumption is inde- 
pendent of the oxygen tension till its pressure is reduced to 0.1 per cent or below”; 
and that under abnormal conditions (pulling of the adductor muscle by a 5-kilogram 
weight attached to one side of a horizontally fixed shell) the gaseous metabolism of 
the oyster is accelerated. 
There are several possible sources of error that may have an effect on the results 
obtained by Mitchell and Nozawa. The natural sea water used in their experiments 
may have contained organic matter that either consumed or liberated oxygen. In 
Nozawa’s experiments the water in the experimental jars was not stirred and its 
oxygen content was probably not uniform. In Mitchell’s experiments part of the 
oxygen was either directly absorbed by the substance of the shells or used up by 
i Submitted for publication May 12, 1930. 
489 
