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GLIN==> Decrease in fish weight out of water (after death) - References ?



Hello :

I'm looking for references that examine changes in weight in freshwater 
fish once removed from water.  For example, how much weight would a 
fish lose after "x" hours or days out of water.  If a record fish is caught 
and weighted immediately - that should be a fairly good representation 
of the fish's live weight.  But if it was weighed again 6 hours or 8 hours 
later or the next day, and not kept in water during that period, what 
would the expected weight loss be in terms of percent of live weight ?  
What would it be if it was kept on ice ?

Obviously, there is no straightforward answer to this question, but it 
is one recently posed to me by an angler.  I looked around for some 
references in NAJFM, TAFS, CJFAS, and have only found one related 
study (below).  I'd like to give him some sort of answer.

Any help ?

Sayers, Richard E., Jr.
Effects of freezing in and out of water on length and weight of Lake 
Michigan bloaters North American Journal of Fisheries Management

ABSTRACT - The purpose of this study was to determine if freezing 
significantly alters the length or weight of bloaters Coregonus hoyi.  
Bloaters were collected from southern Lake Michigan and were frozen 
for periods of 2-200 d.  Freezing in water caused a significant decrease 
in length and a significant increase in weight.  These changes did not 
vary predictably with time.  The mean change in weight was greater for 
adults than for juveniles, but the mean change in length was not 
significantly different between juveniles and adults.  Regressions for 
weight or length after freezing versus weight or length before freezing 
were highly significant and can be used as correction equations for 
estimating the original lengths and weights of fresh specimens after 
fish have been frozen.  Test fish that were subsequently refrozen in air 
shrank more than those refrozen in water.
________________________________________

Shawn P. Good
District Fisheries Biologist
Vermont Dept. of Fish & Wildlife
Pittsford District Office
317 Sanitorium Rd., West Wing
Pittsford, Vermont  05763-9358

Office : (802) 483-2172
Direct : (802) 483-2744
Fax :    (802) 483-9374
Email :  shawn.good@anr.state.vt.us
________________________________________
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