flatties - the $39+ per kilo fillet

[hskim00]

as they seem to be firing.

[

You may be right! Hit a local pier yesterday night and caught two flatties; 45cm and 40cm. Also 5 pinkies were had ranging from 30 cm to 36cm.

[frozenpod]

big flatties are 100% female. They cross dress (aka change sex) when they reach a certain age/length.

Incorrect they do not change sex. The males don't grow as large and the females are not able to reproduce until they become large ie 55cm plus.

[Fish-cador]

big flatties are 100% female. They cross dress (aka change sex) when they reach a certain age/length.

Incorrect they do not change sex. The males don't grow as large and the females are not able to reproduce until they become large ie 55cm plus.

wont argue. Would be very happy to learn and change my understanding about their lifestyles at night. Please show me a reliable article about that - not researches that say "there seems to be no evidence of...."

Still ALL big flatties are females.

[Fish-cador]

as they seem to be firing.

[

You may be right! Hit a local pier yesterday night and caught two flatties; 45cm and 40cm. Also 5 pinkies were had ranging from 30 cm to 36cm.

what do you mean "ÿou may be right"?. I put you and your son on the fish. You got the salmon, right? You tried for flatties and you got them. Maybe next time, I will say I got a hippo from St Kilda Pier and when you chase it and catch one, you will finally believe what I report. I maybe mocking around here a lot but I dont lie about any fishing reports here. :Blah: :cheers: peace!

[frozenpod]

big flatties are 100% female. They cross dress (aka change sex) when they reach a certain age/length.

Incorrect they do not change sex. The males don't grow as large and the females are not able to reproduce until they become large ie 55cm plus.

wont argue. Would be very happy to learn and change my understanding about their lifestyles at night. Please show me a reliable article about that - not researches that say "there seems to be no evidence of...."

Still ALL big flatties are females.

Sure mate there are a number of articles on the reproductive habbits of flathead.

http://www.dpi.nsw.gov.au/__data/assets ... REPORT.pdf

[Fish-cador]

thanks for the info Frozen. Based on that report, several flathead species are known to change sex.... That particular report is specific to dusky flathead and unfortunately, that report is based on a research study that is very carefully worded like ""ärgued that", "suggesting that"", "no evidence of"". Nothing was definite and final. So let them argue about it and leave it to them while we go fishing.

==============

Several platycephalids are known to exhibit protandrous hermaphroditism (Fujii 1971) and it has been argued that dusky flathead undergo protandrous sex change, where individuals first function as males for several years before changing sex (Dredge 1976). This has been based on the observed skewed sex ratios in dusky flathead populations with the smaller size classes being dominated by males and the larger size classes by females. No hermaphroditic fish were observed in this study or in previous studies in NSW (Gray et al. 2002, West 1993), suggesting that dusky flathead do not change sex, but rather male fish do not grow as large or as fast as females. P. indicus (Masuda et al. 2000) and P. bassensis (Jordon 1998) show the same dimorphic growth pattern between sexes with no evidence of protandrous sex change.


Debate also surrounds whether dusky flathead are protandrous sex reversers (i.e., change sex from male to female) (Dredge 1976, SPCC 1981).

==========

I think we better leave this topic here and just agree that we need to protect the big ones as they are the breeders. Cheers. :Bar: :cheers: Tight lines.

[hskim00]

as they seem to be firing.

[

You may be right! Hit a local pier yesterday night and caught two flatties; 45cm and 40cm. Also 5 pinkies were had ranging from 30 cm to 36cm.

what do you mean "ÿou may be right"?. I put you and your son on the fish. You got the salmon, right? You tried for flatties and you got them

.


How do you know I ended up going to St kilda with my boy last Friday??? I have not followed up on my session with my boy and have made no commets about sambos (actually two) caught by me and my son in this forum at all; just too tired after the session with my boy as you can imagine. Well... I can guess who you are if you were the one getting out your spinning gears in the parking area as I was leaving??? :wave2: Thank you for your help anyway. Had a great day out with my boy in relaxing environment at St kilda pier, with less anglers but more tourists.

what do you mean "ÿou may be right"?
I mean I caught them at another place (not St kilda pier) by chance while I was chasing snappers last Saturday night, and after catching one I changed setup on one of my rods for flatties and got another one. And this was before I heard your report. So simply I supported your comments "They seem to be firing" by adding my report too.

[Fish-cador]

How do you know I ended up going to St kilda with my boy last Friday???

what do you mean "ÿou may be right"?
I mean I caught them at another place (not St kilda pier) by chance while I was chasing snappers last Saturday night, and after catching one I changed setup on one of my rods for flatties and got another one. And this was before I heard your report. So simply I supported your comments "They seem to be firing" by adding my report too.

there was only one father and son tandem in St Kilda pier. The boy was wearing blue if I remember it right.

Spinning gear? That fitted my description as I went for a spin session there on Friday and got my flatties.

[frozenpod]

thanks for the info Frozen. Based on that report, several flathead species are known to change sex.... That particular report is specific to dusky flathead and unfortunately, that report is based on a research study that is very carefully worded like ""ärgued that", "suggesting that"", "no evidence of"". Nothing was definite and final. So let them argue about it and leave it to them while we go fishing.

==============

Several platycephalids are known to exhibit protandrous hermaphroditism (Fujii 1971) and it has been argued that dusky flathead undergo protandrous sex change, where individuals first function as males for several years before changing sex (Dredge 1976). This has been based on the observed skewed sex ratios in dusky flathead populations with the smaller size classes being dominated by males and the larger size classes by females. No hermaphroditic fish were observed in this study or in previous studies in NSW (Gray et al. 2002, West 1993), suggesting that dusky flathead do not change sex, but rather male fish do not grow as large or as fast as females. P. indicus (Masuda et al. 2000) and P. bassensis (Jordon 1998) show the same dimorphic growth pattern between sexes with no evidence of protandrous sex change.


Debate also surrounds whether dusky flathead are protandrous sex reversers (i.e., change sex from male to female) (Dredge 1976, SPCC 1981).

==========

I think we better leave this topic here and just agree that we need to protect the big ones as they are the breeders. Cheers. :Bar: :cheers: Tight lines.

Interesting point of view I strongly suggest you read the report again in more detail. If you can provide evidence that they do infact change sex I would be interested to read it.

There have been other studies which also found no flathead ie sand, that had both male and female gonads. This indicates it is not possible for a sex change. The so called flathead sex change as far as I am aware is based on a species of catfish which is commonly called lizard/flathead that has both male and female gonads and are believed to change sex.


This comes from NSW DPI who performed the above investigation and are currently investigating other flathead species in more detail. I would expect a similar report to the above dusky flathead investigation to come out soon.

The lack of sex changing that we observed appears consistent with other flathead species throughout Australia. I am currently working on the life history characteristics of Bluespotted, Tiger, Freespine, Longspine and Mud flathead. All these species as well as ones previously studied in Western Australia and Tasmania show different growth patterns between sexes with no evidence of sex change as we found for Dusky flathead. It appears females just growth larger than males. There also does not appear to be any evidence to suggest that large females are unable to spawn.

As far as the scientific name, all flathead are from the family Platycephalidae which includes approximately 15 genera. Platycephalus is one of the 15 genera of Platycephalidae . Fuscus does refer to the species name for Dusky flathead.

I hope to be publishing papers on the life history of these other flathead species in the next little while so keep your eye out if you are interested.

If you have any other questions please don;t hesitate in contacting me.

Lachlan

I was reading the July 2007 issue of Modern Fishing and came across the letter 'Lizard Lore', from a fellow reader (Anthony Willebrands-DL) and thought I may be able to provide a few answers in regards to the Flathead biology. I'm currently finishing my PHD through the centre for Fish and Fisheries Research at Murdoch University in Western Australia, in which I am investigating the biology of the Yellowtail Flathead and the Western Blue Groper and Blue Morwong.

During this study of the Yellowtail Flathead, (Platycephalus endrachtensis), in the Swan river estuary in Perth, we found several characteristics that Anthony Willebrands and other fellow Flathead lovers may like to know. Even though the Yellowtail Flathead can not reach the extraordinary lengths and weights to that of the Dusky Flathead, it does share the same characteristics of females and males having markedly different growth rates. The females and males of the Yellowtail Flathead attain a maximum length of 615mm and 374mm respectively. If you were only to see this result , you could be forgiven for assuming that this species is a protandrous hermaphrodite( male and female sex change). However, we also found that both sexes are present at all age classes from a age of one year old to the maximum of 9 years, recorded for both sexes.

Further investigation of the reproductive organs, overies and testes of Yellowtail flathead found no evidence of male and female reproductive tissue occurig together-a key indication of possible sex change. Our conclusion was that Yellowtail Flathead were dioecious ( Speparate sexes), with females and males possessing markedly different growth rates.

In other studies of Flatheads in the genus Platycephalis, including the Dusky (P.fuscus), Southern blue-spotted Flathead(P.speculator), Sand Flathead (P.Bassensis), Tiger Flathead(P.richardsoni) and the bar tailed flathead(P.indicus), similar results of femailes attaining a larger size have been found. Furthermore, none of these scientific studies found any evidence of sex change in these species.

The thought that Dusky Flathead may change sex may could have come about from literature describing the biology of other members of the Platcephalid family, including several species found in Japanese waters, such as the Lizard Flathead(Inegocia japonica). They do change sex from male to female. In species where the large fish are females not just in Flathead, it is imperative that we try to protect these large fish because it is these individuals that have the greatest reproductive output; they are able to produce hundreds of thousands or even millions of eggs.

To think that these large Dusky Flatheads are barren is not correct. Kind Regards Pete C.

Peter Coulson, Centre for Fish and Fisheries Research , South St. Murdoch, WA 6150