486 
Fishery Bulletin 107(4) 
gardless of the environment, phase angles decreased 
with impaired fish condition. The use of phase angle 
as a direct measure of nutritional status and possibly 
general health can bridge the gap between indirect 
nonspecific measures such as length-weight indices 
and direct specific measures of physiological param- 
eters that are obtained through laboratory analysis. 
Furthermore, phase angle allows real-time direct mea- 
surements of condition in fish in the field without the 
need to sacrifice them. The low cost and rudimentary 
technical expertise required to conduct phase angle 
measurements will allow field biologists and techni- 
cians to effectively measure the condition of fish and 
apply these measurements on broad ecological scales. 
Although variables were controlled as much as possible 
in this study, further research should be undertaken 
to investigate additional potential sources of error that 
may affect these measures and should include tem- 
perature and time of measurement after death as well 
as the configuration, gauge, and depth of needles used 
during measurements. 
Acknowledgments 
The authors would like to thank NOAA Alaska Fisheries 
Science Center for providing funding for this project and 
K. Hartman (West Virginia University), J. Silverstein 
(USDA), J. Margraf (University of Alaska, Fairbanks), 
N. Parker (Juneau Douglas High School), and J. J. Vol- 
lenweider (Auke Bay Laboratories) for providing fish 
data. 
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