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Dusky flathead don't change sex

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Dusky flathead don't change sex

Postby davecanfish » Sun Mar 11, 2012 11:29 pm

Came across a DPI study on the dusky flathead written in 2008. I was lead to believe that flatheads were male until they reached a certain size then morphed into females. MMM silly me. :oops:

In the Intro this statement was cited

" Debate also surrounds whether dusky flathead are
protandrous sex reversers (i.e., change sex from male to female) (Dredge 1976, SPCC1981). "

In the discussion is this finding.

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.

The DPI study link ... REPORT.pdf

There are also some interesting findings about the differences in growth, age and size of males and females when ready for reproduction.
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Re: Dusky flathead don't change sex

Postby pink nipper » Mon Mar 12, 2012 9:34 am

Yeah have heard this.

Alot of people still reckon they change sex
but certainly there are more big females than big males.

Nip : winky:
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Re: Dusky flathead don't change sex

Postby Scizz » Thu Mar 15, 2012 2:46 pm

cause they bloody do,these people have no idea,probably str8 out of uni.
fished for and caught flathead all of my life and am yet to see a small female or a big male.

probably the same people who recon you have to kill fish with sores
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Re: Dusky flathead don't change sex

Postby Prof » Thu Mar 15, 2012 7:14 pm

Biggest male I've seen is 67cm smallest female was 42 cm.

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