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Trevor Skinner

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Black GTs are like London Buses...
June 09, 2013, 02:50:32 PM
....you wait for ages for one and two turn up at the same time.

After a succession of bright silver fish at last a couple of big black mamas (down Luke)




Regards,


Trev

Nathan Tsao

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Re: Black GTs are like London Buses...
June 09, 2013, 03:08:32 PM
its kind of strange to me that i notice a bunch of guys here on the forum say that the black GTs are hard to come by. It must have a lot to do with location, because i think that 75% or more of the GT's that i see here in Kona are the blacker ones.

I wonder why it is that they are more rare in other parts of the world???

Nice Fish Trevor!!!

Trevor Skinner

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Re: Black GTs are like London Buses...
June 09, 2013, 03:19:45 PM
Nathan,

I wish they were easier to put alongside the boat! That last fish gave me some real hurry up.

I've asked this question of a few very, very experienced GT fisherman and there seems to be as many answers. What I have noticed is some fish seem naturally black even when chasing the lure while others seem to darken up after hook up and capture. Both these fish were mottled and darkened up considerably after capture.

I've seen both black and silver fish in both Musandam and Halaniyat. The darker fish seem less common but don't have any real numbers.

Regards,



Trevor   

Mark Harris

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Re: Black GTs are like London Buses...
June 09, 2013, 03:32:57 PM
I have seen three theories on this:

1. The VERY dark ones are breeding males. This makes sense in areas where you do not see many and also where those you do catch seem very pumped up and aggressive.

2. Pigmentation from specific diet. This makes sense in areas like Hawaii and parts of the South Pacific where black GTs seems to be the norm rather than the exception.

3. Colour change during hunting (as with some scombrids like sailfish, wahoo etc.). I am not at all convinced about that for GTs.
Last Edit: June 09, 2013, 03:34:56 PM by Mark Harris

Andy Rowe

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Re: Black GTs are like London Buses...
June 09, 2013, 04:26:34 PM
Some more input;

Mark, agreed with your point 1, black ones go harder, testosterone is probably a key ingredient to increased aggression and strength at least in the areas around Indonesia from my experience. The darker fish are not as common in the Indonesian fishery and I note the black ones generally fight 5-10kg above their weight.

point 2, that is interesting, also consider camouflage, the dark basaltic rocks of hawaii and Eaio appear to produce a disproportionate number of dark fish, perhaps the darker coloration here is a result of natural selection where darker fish are more successful in ambush situations. Or it may be a case where the fish can readily change colour to match the back drop. Interesting to note also are localised dark spots in lighter coloured fish, this appears to be related to areas  where the lure has rubbed on the fishes face.

It's an interesting point and I think there may be several reasons for dark fish but I'd presume the case of the inordinately strong + black fish to be males.



Last Edit: June 09, 2013, 04:28:42 PM by Andy Rowe
Set the ray to GeeT

Mark Harris

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Re: Black GTs are like London Buses...
June 09, 2013, 04:44:44 PM
Good points Andy.

The camouflage and diet points may be related - i.e. the need for camouflage against those dark basaltic rocks is met by something specific in the diet.

I also forgot to mention some anecdotal evidence for the breeding males theory. I can remember several occasions when a very black GT I caught has been very milty.  I know others have mentioned this as well.


Ed Nicholas

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Re: Black GTs are like London Buses...
June 09, 2013, 06:56:45 PM
Awesome fish Trev. We landed way more Black Geets through April than at any other time of year down here and alot of them were heavily laden with sperm often squirting it out on deck adding to the projectile vomit, sh*t and slime that covered us from these beasts.

Is there really no information around on identifying M/F GTs, age of the fish etc? I find it astonishing that there are so many of us chasing these fish yet we know pretty much sweet F-A about them. We can find hundreds of threads on how to catch them, the best lures etc but info about the fish themselves is like gold dust.

Trevor Skinner

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Re: Black GTs are like London Buses...
June 09, 2013, 07:08:29 PM
Ed,

Seriously, if Mark can't control his bodily functions and keeps making a mess of your boats like that you should ban him. It's just not polite let alone unhygenic.




Trev



 

Ed Nicholas

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Re: Black GTs are like London Buses...
June 09, 2013, 07:13:06 PM
Haha thats gold  :)

Mark Harris

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Re: Black GTs are like London Buses...
June 09, 2013, 07:14:01 PM
Even I will admit that is very funny! :)

Mark Harris

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Re: Black GTs are like London Buses...
June 09, 2013, 07:25:43 PM
The harry monk all over my shirt in this pic has absolutely nothing to do with me though.


dante green

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Re: Black GTs are like London Buses...
June 09, 2013, 07:35:23 PM
....you wait for ages for one and two turn up at the same time.

After a succession of bright silver fish at last a couple of big black mamas (down Luke)
Sorry to tell you this, but those aren't black gt'ss. Black gt's has a deeper slant forehead.



Regards,


Trev

Mark Harris

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Re: Black GTs are like London Buses...
June 09, 2013, 07:41:38 PM
Dante - a black GT is not a species.. it is a colour variant of GT.

If you mean Black Trevally (caranx lugubris)...... that's a completely different species of fish and is not being discussed here.

Trevor Skinner

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Re: Black GTs are like London Buses...
June 09, 2013, 08:37:43 PM
Awesome fish Trev. We landed way more Black Geets through April than at any other time of year down here and alot of them were heavily laden with sperm often squirting it out on deck adding to the projectile vomit, sh*t and slime that covered us from these beasts.


Ed,

On second thoughts and to save considerable embarrassment to Mark, you could rename your boat 'The Barasti'


Trev

Nick Bowles

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Re: Black GTs are like London Buses...
June 10, 2013, 02:02:23 AM
Eish Mark think you caught the wrong end of the stick there! Think I remember seeing Mr Luke with an excited GT as well trying to blame the poor fish!

Same story as where the big GTs come from, black GTs are a bit of a mystery and seems to be something to do with spawning in Oman but then in Seychelles almost all of the fish are silver/white so also think the whole environment they hunt in is a factor to some extent. Chameleon type scenario. Seychelles mainly white flats very silver almost white GTs, Oman/Hawaii/Tokara deep water with volcanic or dark structure and the fish are generally darker. Agree with Ed, there is a lot about fishing for GTs but not much we now about them! Hopefully we can understand them more in the future!

Another good one to discuss around the fire!

Cheers,
Nick