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General => General Topwater & Jigging Discussion => Topic started by: Geoff Volter on August 26, 2008, 11:43:13 PM

Title: black GT's
Post by: Geoff Volter on August 26, 2008, 11:43:13 PM
I'm sure somebody has a theory or an answer- but what is the thinking on why some GT's in an area are black?

At midway it looks as though most are black, yet in other area's there is a mix...

Just wondering.
Title: Re: black GT's
Post by: Jon Li on August 27, 2008, 02:12:03 AM
According the Japanese GT anglers , the black colored GTs are full of eggs . Now I can't substantiate this because we release all the GTs we caught .

Jon .
Title: Re: black GT's
Post by: Warwick Joyce on August 27, 2008, 08:07:12 AM
When fishing in north qld we were catching mostly silver/gray gt's however 2 fish were landed were quite dark bordering on the black color you are talking about. Maybe it is the egg thing???
Title: Re: black GT's
Post by: Brandon Khoo on August 27, 2008, 08:57:09 AM
I've seen them literally change colour from silver to a much darker colour while in the boat.
Title: Re: black GT's
Post by: Luke Wyrsta on August 27, 2008, 09:14:04 AM
I've seen them literally change colour from silver to a much darker colour while in the boat.

That's a tough one - my speculation is that is more related to stress than anything.

I do agree that GT's in the water or amongst other GTs are getting ready for breeding.
Title: Re: black GT's
Post by: Darren Cook on August 27, 2008, 09:35:34 AM
I've read a theory that the black ones are males, full of testosterone and ready to breed.
The extra testosterone making them more aggressive and harder fighting but I've never caught one, wouldn't know how they  pull.

There's a great scene in "Legends 5" where Okubo lands 2 small black GT's on one popper. They were obviously cruising together.
Title: Re: black GT's
Post by: Jay Burgess on August 27, 2008, 01:14:49 PM
When I was at the Rowleys I saw a black/silver pair hit my popper simultaneously. Unfortunately the silver one hooked up :( Anyway, it seems that they quite often pair up, perhaps it's a male/female pair during spawning or something?
Title: Re: black GT's
Post by: Peter Lowe on August 27, 2008, 03:42:55 PM
Dont you guys watch the movies - their is always a TOKEN  - ::)

 - he also always dies first too........


 :D



 8)
Title: Re: black GT's
Post by: Brock Arifovic on August 27, 2008, 06:44:36 PM
Very good point you have bought across Crazy, but it still doesn't help me to catch 1  :D :D :D :D :D

one day maybe, i will just have to get out & fish more often, things to do places to be.
this is my new mission. hopefully we can get a few each together one day????
Title: Re: black GT's
Post by: Aaron Concord on August 27, 2008, 08:04:38 PM
In the clear water of the Coral Sea, I've seen a heap of individual and multiple G's 'turn black' when aggressive and about to pulverise a popper or stick bait.
This has happened more when there are a group of G's and their is obvious competion for the lure.
Most are silver/grey to blend in with the reef flats & edges, though go pitch black when fired up.
Maybe they are Males full of baby batter...haven't taken the life of one to check out its 'nads to be certain!
Title: Re: black GT's
Post by: Andy Rowe on September 23, 2008, 11:32:19 PM
More information to support the black coloration of the male GT in this article. It's becoming more conclusive that the darker dorsal coloration is assumed by males during courtship and spawning. Hence one may infer testosterone boosted fighting qualities of the darker fish. See the later part of this article.

http://zoolstud.sinica.edu.tw/Journals/46.2/186.pdf
 (http://zoolstud.sinica.edu.tw/Journals/46.2/186.pdf)
It also appears you may come across hybrids, GT and Bigeye trevalies can hybridise with Bluefin trev's, so don't be surprised if you catch what appears to be a 50 Kg Blue GT :o. Though this appears to happen more in locked lagoons.

I don't have a 'Nature' subscription but if anyone does, would they be so kind as to share this article??

http://www.nature.com/nature/journal.../178934a0.html (http://www.nature.com/nature/journal.../178934a0.html)

Seems this journal article is focused on the sexual color differences of our favorite Trevally.

Cheers