Richmond River Cod - Seeking Info

[Jim_Tait]

Mick - sent you a PM

Regards - Jim

[MikeC]

Hi I'm no expert so I'd like to know if it's easy to distinguish Eastern cod from Murray cod. Maybe you could provide some info along those lines. I wouldn't like to think any Easterns could be kept by 'mistake'. Thanks.

[Jim_Tait]

Mike,
Eastern Freshwater Cod (EFC) and Murray Cod (MC) are not that easily distinguished - even the 'experts' find it difficult. Taxanomically you can note features such as loger pelvic fin filaments in EFC, but generallythe range for almost all of the fin rays, gill raker, lateral line scales, vertebrae etc counts overlap.
The key point is that EFC & MC do not overlap in distribution unless MC have been stocked into EFC habitat or vice versa. If fishing within EFC range - best (& legal) practice is to release all cod - as you would be hard pressed to prove a cod was not an EFC if in their natural range.

Regards - Jim

[MikeC]

Thanks Jim. Interesting. [First time I read thru I missed the bit about all cod in eastern-flowing streams having to be released.]

[Fitzy]

Mike,
Eastern Freshwater Cod (EFC) and Murray Cod (MC) are not that easily distinguished - even the 'experts' find it difficult. Taxanomically you can note features such as loger pelvic fin filaments in EFC, but generallythe range for almost all of the fin rays, gill raker, lateral line scales, vertebrae etc counts overlap.
The key point is that EFC & MC do not overlap in distribution unless MC have been stocked into EFC habitat or vice versa. If fishing within EFC range - best (& legal) practice is to release all cod - as you would be hard pressed to prove a cod was not an EFC if in their natural range.

Regards - Jim

Jim with all of the work (& fishing) you've done on the various freshwater cods, do you recon you can pick the difference in them with a casual glance? I've caught bugger all ECC but I recon I can pick the MRC & the MCs. Noting I've never been in the situation where I've had the 2 side by side. Have caught both of them from Big W. There were some farm dams with MCs in them when Big W was built & they were subsequently released by lake waters. A mate caught what we thought was an MC so it was taken to be sussed out; turned out we were right.

Do you think the location & environment makes a great deal of difference in the coloration? I think so but would like your thoughts.

fitzy..

[Jim_Tait]

G'day Fitzy,
I reakon I would be hard pressed to tell a MRC and EFC appart but probably could tell a MC appart from either of the former - though people who's opinion I respect who have had a lot more experience with cod i.e. Stuart Rowland - reakon that they have seen MC that exhibit characteristics that eclipse the range of characteristics shown by either MRC or EFC.

Generally I note that EFC & MRC always have long pelvic fin filaments (which I have never seen on MC but I am told they can have them), more 'eye spot' mottling as opposed to finer grained spots on MC and a bit more of a humpy (like a barra) head profile.

Re influence of habitat on colouration I have not caught MC from a wide enough range (after all I'm basically a north queensland johny come lately to this southern country) - but note that pictures of MC I see in publications caught in the New England Gorge country look fairly different to those I used to catch in teh bidgee around Canberra - this could be genetic as well as environmental as I belive the cod populations show a bit of differentiation throughout the MDB.

Regards - Jim PS attached image of MRC will post image of similar sized MC in following post

[Jim_Tait]

Murray codfor comparison - not real flash image but note the pelvic fins - Jim