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Housedave
23-01-2019, 02:37 PM
Hi
I am doing a bit of research into shrinkage of post capture fish. After being away this Christmas break we noticed just how much fish can shrink once caught. Subsequently i found a great article in Fishing Monthly which confirmed and surprised me just how much a fish can shrink. According to the Fishing monthly article fish can shrink 10mm in just over 2 hours. To any fisherman this can present huge implications with Fisheries, depending on the time the fish are measured.

The article goes on to say that;



Post mortem shrinkage of fish can pose serious risks to fishers, and complex challenges for those in compliance and judicial positions. For those species in which it has been observed, shrinkage happens fastest in the first hours after death and happens faster in fish held in ambient/warm conditions than those chilled or iced.
Legal-sized King George whiting measuring up to 5mm above the MLL may shrink by up to 8mm within a few hours of capture.
Shrinkage of snapper occurs faster over the first 6 hours after death and is virtually complete after 24 hours. For those measuring close to the MLL, the reported shrinkage averaged 5.5mm and ranged from 2-9mm.


https://www.outdoornews.com/2015/08/31/study-shows-that-fish-shrink-after-icing/

http://www.fishingmonthly.com.au/Articles/Display/18726-Post-capture-shrinkage-of-fish

Anyway i would appreciate if you have had any personal experience with shrinkage post capture and in particular experience with fisheries where fish that were legal when caught post capture shrunk below MML.

Dave

scottar
23-01-2019, 05:35 PM
Good mate of mine got pinged for a snapper that had shrunk.

Noelm
24-01-2019, 09:34 AM
10mm might be a tad optimistic, but fish certainly shrink a few mm, probably a good reason to release a fish that is "just on" I am by no means a greenie, but anything I catch that I think needs measuring goes back, most minimum size fish are not worth keeping.

NAGG
24-01-2019, 10:51 AM
It makes sense specially if a fish loses moisture like where a fish is kept with bottles of frozen water as opposed to kept in an ice slurry .

I've always been of the belief that is you have to manipulate , distort or remeasure a fish then it needs to go back as the last thing I want to be doing is arguing the toss with a government authority .

Chris

FINICKY
31-01-2019, 09:57 PM
When we go up north for four day trips or do overnighters around Brisbane I won’t keep anything unless it’s at least 3cm over legal.
This is due to fish shrinkage and also due to fish going stiff in an Esky full of ice and not lying flat when being measured at a later date.
On the same note, a 35cm squire isn’t really worth keeping if you’ve got the possibility of upgrading later in the night or the next morning. Anything under 40 is only kept when things are looking bleak and struggling to get a bag together.



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TREVELLY
01-02-2019, 07:09 AM
I agree 100% this fish was way legal and easily 3kg, until it was caught - good thing we went the safe option and released it

TomTom22
20-02-2019, 07:22 AM
About 12 months ago we got a legal red up at Fitzroy and when i say legal it was somewhere between 55-56cm. but who throws back a legal red?
anyway that arvo in the lagoon we were having a look and it had shrunk under 55cm. no amount of manipulating/stretching was getting it back there either lol
On another note how good are fresh red emperor sandwiches.

Homer_Jay
21-02-2019, 05:51 AM
Yeah we have had them shrink by a cm on longer 3-4 day trips. And these are kept in an ice slurry.
Not worth keeping anything that is right on the limit.