New species of grouper from the Andaman islands

[Siam Spearo]

Hi Guys,

What is this grouper? I have not seen one before, my mate caught one at the Andaman islands.
We, Andaman Spearfishing, are now offering trips to this destination. We have both 7 day and 12 day trips, this is the best destination on the planet! we have seen huge blacks and grander blues are def cruising the deep blue!
Monster GT, Massive Doggies, Sailys, Huge Wahoo, Mahi, Milkfish, 2.5m Cuda.
I love hunting the deeper reefs for snapper, in thailand a 4kg red snapper is a prize fish, grouper over 15kg are prize. In the Andamans you can add a zero to each of the previous figures! No bullshit.

If you are interested in our next trip in March 2009 then P.M me. In the meantime, what the hell is that fish?

 

[Siam Spearo]

Here it isblackeye

 

[spadefish]

Hi Siam,

It seems to be a yellowfin rockcod (grouper) - Epinephelus Flavocaeruleus. The one you have is quite a big one to still have the yellow markings (this tends to indicate that there is probably a far bigger one on the same reef preventing the full adult colour change to happen). When large, the yellow starts to be replaced with the same black/purple colour the rest of the body is. Incidentally the last part of the body to change colour is the portion between the eyes to the mouth. The white spots on the body remain there throughout the age of the fish and can be distinct or faint depending on how excited the fish is.

In SA, we get a lot of small ones (up to 3kg) in shallow water (20m) with the big fish generally found in deeper water and offshore reefs where there is deep water around.

I hope this helps.

CIAO

 

[Siam Spearo]

Hi Spade fish,

I thought it may have been a young yellow fin but couldn't understand why it was so big and still with the yellow fins.
I think your right though it would explain it being so big and still looking so young, the other one must be massive because this is a really big one.


Thanks for clearing it up.

 

[spadefish]

Hi Siam,

I have seen them up to 20kg (I assisted in getting one of this size out of a small cave) and believe some scuba divers have seen them up to 40kg in very deep water (<50m). I think being territorial (especially if the reef is isolated from other reef) a dominant male will pervent a large fish changing from female to male. This is my theory and have not seen a scientific publicaltion showing the relationship between colour change and sex. I have seen a photo of one taken on scuba - the fish was about 10kg and still had the yellow markings on its head.

How big was the one you got - it is a splendid fish!

CIAO

 

[spadefish]

Hi Siam,

Just had annother look at your fish, the tail has already changed to black. Perhaps it was in the process of changing!

CIAO

 

[Siam Spearo]

NOt sure, my mate caught it rod and line, he let it go because he had never seen one before. Looks like about 6kg, the Thai guy is holding out to make it look big :head:head

interesting theory, other fish such as parrot fish will only have one female per group, i know grouper don't live in groups, but they do live in a close society and one big ass grouper would stop others from changing sex, in theory.

I have heard that grouper will stop reproducing when they get too big and old, kind of like women:blackeye
One of my diving buddies targets HUGE grouper as he says they keep the other grouper from maturing and eat everything that fits in their mouths, which is pretty much everything.

He is a man of the sea and is usually right about this kind of thing.

Wondering if you have heard of this, you seem to know what you are talking about.

 

[spadefish]

Hi Sian,

Generally groupers change sex from female to male at a certain length, so it can be assumed that the really big ones are males. By taking them out I suppose is like taking out trophy deer - the main difference is that the next male will probably come from the oldest female. I think these big fish will always station on the best spot on the reef. Take him out and the next biggest will move into the same zone (or cave). I have never heard of them losing fertility with age (maybe someone out there can correct me).

These big fish - especially with some of the more agressive groupers become a problem (potato bass in particular - vile things!!!!!) in that they always seen to be able to grab your fish and destroy your equipment. I think that these big fish do not prevent the other fish 'maturing' but rather keep them as females (they will still grow - so in theory there sould be others - smaller - of the same species on the reef). I have noticed that here, with big groupers (eg malabar) that there will only be one on a section of reef, but in Mozambique you can have a whole bunch on one wreck, so perhaps fish behave differently in different locations.

These are my thought on the matter.

CIAO

 

[Siam Spearo]

Yep, if the biguns change to male it would make sense to assume that. Here in Thailand we can get a few 40kg plus grouper on a 1km stretch of reef. I have seen some over 100kg but they are to smart and too deep. We get a lot of bullhead grouper here, how big do they get before they start to change in general or does it really depend on how big the larger groupers are in the area.

We tend to take a lot of bullhead in the 7-10kg range, i think this is a good thing as long as they have changed to male as it is the females that are most important. One male can help a whole lot of females.:chatup

We used to get giant grouper too, but they have all been cleared out, unless the 100kg grouper I have seen are giants and not just huge bullheads, not sure I can't get to close to them, they are at about 50m, way deeper than I can dive:head

 

[spadefish]

Howzit,

There in SA, giant grouper are protected. We see them on some of the deeper wrecks - in one place if the viz is OK you can see a dozen of them looking at you - all fish bigger than 200kg. Quite nice actually!

I will have to lookup what a bullhead grouper is - it is not a name we use here (probably a species we do not get here).

As for the yellowfin groupers, when they get very big, they usually appear to be totally black underwater. The main difference in profile between them and the giant grouper is that the giant is a little longer (ie the ratio if height to length is lower). Clearly if you see a fish which is in 50m of water and you are in 35m, all you will see is the length - not easy to ID. Giant grouper also have quite light (tan/yellow) pectoral fins - even the big ones.

Cheers