murray and mary river cod difference?

[wesfish]

after catching my first murray the other day at pindari and looking at pics of mary and murray i can not see that much difference in the 2 species. after talking to my dad today he informs me of some stocking of murray cod in the head waters of somerset and wivenhoe by a he shall not be named person that will know who they are apperently they let about 200 murrays go in various locations about 15-20 years ago. this now has me wondering weather the cod getting caught up that way are murray or mary? how do you tell the difference exactly? and would the murray cod breed this far north? any help with this topic would be much appreciated

cheers

wes

[wesfish]

here is the murray i caught, if some one could put a good pic of a stanley river mary up to see the difference please

[wesfish]

another not so clear but easier to id head shape.

[Feral]

I have seen stocking info that claims Murrays went in to Somerset in the 70's. But its was only in one document and I've not seen any mention elsewhere.

There is also apparently some reasonable evidence that Murray's were put in the Mary river at one stage as well. One of the things that was supposed to happen with the Mary River Cod recovery plan was genetic and DNA studies to determine how closely related they are, and whether there had been any cross breeding. All 4 of the cod types are very hard to tell apart, only very minor differences like length of lips, whether it protrudes or not, slight concave or convex on the head, of course full size and breeding habits are different, but that doesn't mean they are not genetically similar, just that natural selection has been at work.

[elops]

mary

[elops]

mary again

[elops]

As Feral said its hard to tell the 4 species apart very minor differences in morphology with Trout cod being the only one that is easy to distinguish.

Another Mary sorry about pic but it does show one distinct identification key.

Steve

[wesfish]

cheers feral and steve