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[quote=”Peter Finke” post=1752][quote=”Stefanie” post=1751] But what should I be patient for, then? If they’re definitely all females …………[/quote]
Who said “definitely”? Nobody. It’s a hypothesis. [/quote]
Hm. I don’t want to quarrel about it, but I said
I received a very disillusioning mail from Martin Hallmann today – he is convinced that I only have females ………..
and then you said
I think Martin is right as I said already
For me that’s quite clearly spoken …….. no hypothesis. Or is there a hidden meaning in the word “convinced”, which I do not know??
Now you say:
don’t exclude females at all. We cannot be sure from your desriptions and pictures. This at least is what I said. It’s a possibility that has to be taken serious. And you have not seen it like this before; you thought of males only.
I never thought of males only. That’s simply not true.
I thought of maybe having one single male (and even with that I was never sure, that’s why I showed the photos and asked for opinions), and I was always sure to have at least to females.😉 Without a doubt a male !
Thats good news, it really is annoying when it sometimes happen that you end up with only one sex. I have tried it with some species, as I think I have written earlier somewhere, – but that has always been males only. And for this reason I have become really careful now when / if bying fish in stores.
Because many times you also are unable to get more fish that with certainty is the same species, so its really an unfortunate situation if theres only one sex.
Now for sure you have a male – and I would think more females, – but then it would be really good if they got offspring.
At some point I found some p.nagyi in my shop, wildcaught, and I had to buy some. I got back with at least 12, – two females. They developed a lot of problems, took long time before they ‘thrived’, so I lost so many of them untill in the end all I had left was one pair. They fortunately spawned and had two offsprings. Two males. Then the old male died. Now I had the mother and two sons.
I really wanted to keep this species, so I was hoping … and luckily, now, I still have the mother, the two sons + 3 new offsprings. And I really hope one or more will be females, – then there might be a chance of keeping on having this species in my tanks.I congratulate you with the fact that you do obviously have at least one pair. Which species is still to me something which will be for a later point to determine.
One always should bear in mind that the sex of a fish-individual is not determined in the moment of fertilization (as we know it with mammals or birds) but happens days or weeks later by environmental factors. Temperature, pH, the content of humic substances and other factors: all could contribute to the decision. We sometimes have an outcome totally of either one sex or the other; then one or several of these factors have been near to a limiting value during the first life-time of the young.
Another thing is the fact that in the trade of wild caught Paros sometimes only one sex is sold. Some years ago a German wholesaler asked me by two photos which species it is; the official name was – as usual – “deissneri”. It was spec. Sentang (of course), but the striking fact was: the photos showed only male individuals, about 200 or more (see photo of similar situation below). I had for long no explanation for this phenomenon. Nobody has the time or reason to select the fish artificially. But there is a worrying explanation: More and more the habitats are damaged by many factors (e.g. chemical pollution). Often we find Paros today no longer in their traditional natural rainforest habitats (because they are destroyed) but in poor side canals of roads and other water bodies heavily changed by human activity. Take light only: If the rainforest is gone, there is much more light than before. The huge mass of leaves and wood formerly falling down into the waters is missing. The pH changes, often the temperature is higher (or lower) than before. Therefore we cannot exclude that such monosex offspring is to be found in “nature” already.
Actually, I sometimes have the same problem with my ‘own’ offspring. I have species which produce a very uneven number of the two sexes, – in particular p. harveyi. Most of the offspring are males. And of course, I also reflect over this situation that I think one or more factors are ‘wrong’ – and I am trying to figure out which and change it.
So of course it really makes sense what you are writing Peter, – that one could worry that enviromental changes could have this effect on the fishes in the habitat.
That sounds very worrying.Dear Helene, yes, it is very worrying indeed. The most worrying thing is the situation of the natural habitats. I often meet people who say: Well, it’s a pity what is happying there, but there are still all species present.
Yes, as far as we know all which we know are living still the present day. But we can be pretty sure that some are no longer to be found which we have never encoutered.
And the other thing that is not to be forgotten is: “Fish present” don’t not mean: “Fish healthy and natural stock without any problems; everything in order”. We have more and more reason to believe that the genetic stock of many animal species (whether of insects or amphibians or fish, etc.) are partly affected by environmental damage. Think of the huge amounts of environmental toxins and poisons that are spread in the air especially in the tropics, for isntance the countreis in south-east Asia that hope to improve their economic welfare by the huge palm-oil plantations. Much of this must get into the soil and rivers, and nobody cares.
With fish, the most likely indication is not clear outer damage of their bodies or their behaviour, but in the first line the sex ratio. The best thing I can say at this issue is: We have a few clear cases only so far.
But it is quite obvious with aquarium fish although we do not spray environmental poisons into our tanks, of course. But we must control the environmental factors we place at their disposal. Too cool or too warm, too high pH (too low is hardly possible), too high a calcium content, missing humic substances, too many germs: all could contribute to a misture with the result of an uneven sex ratio.
The difficulty is: All this works together, is a complex system. You cannot say: temperature too high, or pH too high, and so on. There is an interrelation vice versa that make things difficult. This is what science tell us. It cannot tell us for each single case: That’s it. You must assess it yourself as open minded as possible.
Nevertheless, one should not be frightened: Mostly things work out quite well. But one should know this system of environmental factors that influence the final determination of sex in fishes.
It is disturbing to think that in nature, due to outside influences that a species could/will produce very skewed sex ratios. Due to survival instincts and the drive to reproduce, it is quite possible to see “natural” hybridations also.
A possible example might be the new Ampah which is being sold as Filementosus and is more than likely being collected from the Filamentosus collection sites. It seems a little strange that this “species” just showed up and in large numbers. Don’t get me wrong, I’m not saying this happened, but it could with many species of Paros as their wild population decrease.
Just a thought here but disturbing, new species could be evolving with the ability to survive in the new man made enviroments.. we would notice this in changes to the fish with difficulty to identify.
I understand that in the natural enviroment hybrids rarely survive, but what is going on is not natural. I have seen this happen once where man has interfered.
Correction, maybe I should not use the word species, as much as different “forms” of a species.
What you described is already known with guppies. At places the adults are caught away the fish stay smaller and mature earlier. This is due to genetic change, so evolution. Url: http://www.nrcresearchpress.com/doi/abs/10.1139/f05-079#.URaBLqU0EWs
[quote=”helene” post=1783];) Without a doubt a male ![/quote]
I think if this is a male, it’s the only one I have. The others to me are doubtlessly females. It’s not easy to make good photos because of the position of the tank and the relative shyness of the fish.
Here you see the second bigger fish and a small companion , in the back the one I think to be a male.
The two in the foreground which I mean to be females have more rounded dorsal fins, the supposed male has a more pointed dorsal fin. And the caudals of the females are transparent and without any pattern.
Since yesterday the third, smallest female constantly shows something I take for a courtship colouration (sorry for the quality):
Is this a further indication for the presence of a male – or do females show courtship colouration even if males are absent?
Hello Stefanie.
I do think that you have a male, the band in the caudal is not to be seen in females.
The behaviour you are talking about with the one female, well … I think that if its spawning behaviour its a good suggestion that theres a male in the tank. Females alone will not do that.I have found that if you keep more fish together the courtship between one female and one male is a bit prohibited, – it will occur, but if you seperated the pair it might show up much more clear. So if you have a feeling that theres one female showing courtship behaviour, let that one female be the only female with the male, and see what happens. With one male, you also really might want to make sure that there is offspring 😉 – and this is much more likely to happen with just the one pair in the tank. Two extra females is going to make it difficult.
Thank you, Helene.
Yes, I also have the impression that the females irritate each other. They now and then show something I would call “catfight”, you can see it on the first picture – trying to impress each other, showing off, then from time to time chasing each other.
I am slightly irritated that the male doesn’t really colour up. To me it seems quite long til he shows his colours …….. in my nagyi you could clearly distinguish the sexes after one or two days.
I think the male not colouring up could have two reasons
1 – he might be young, only just maturing. Some paros are slow in maturing. The female might also be young, so the courtship behaviour is not all that strong yet.
2 – The two ‘extra’ fish might also disturb his behaviour, one of them might be another male..Again, I think the best way would be to give a potential couple the tank on their own, provide an attractive cave, – then it will probably show up more quick if something is going on.
I hope you forgive me some more bad pictures ……… I have to take photographs while I feed the fish, to have them near to the front pane instead of keeping in the darker background. So there are a lot of reflecting artemia and glass worms … I’m sorry for that.
But I would like to show you the colours he is beginning to show or which in my opinion seem to deepen.
Here first another picture that shows the pattern in the tail fin, a bit softer this time:
You have to look real close, I hope you see what I see: The dark rounded pattern at the base of the tail fin is a deep chestnut red. So are the dorsal and the anal fin, they both have a dark, almost black outer border with a white seam. The pelvic fins start to show an emerald green.
The unpaired fins have a real strong crystalline gloss, like glass. Here it is rather obvious:
I know that the pictures are unsufficient – but I believe to see very much red colouration, and hope I can transfer this impression.
Martin Hallmann just told me at the IGL-Forum that he still is convinced of all my fish being females ……….. the “male looking” one is a dominant female in his opinion.
He only sees a small chance that one of the small ones comes out to be a male ….Martin Hallmann of course has years more experience than I, so maybe he is right. However, the one fish that were on the photo in post 1782 – I would myself feel certain that that was a male. I have never seen a female with that clear pattern in the caudal fin.
But theres no point in discussing this really .. its always a bit difficult, and I dont want to claim I know better than Martin 🙂 ..
I try to give the advice as good as I can from the images you bring. I mentioned in one of my first answers here to you that I thought most fish looked female, – so maybe they are after all.
But the photo in 1782 ?I would hope for you that its a male .. 🙂
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