Goldfish / Goldfisch / Carassius auratus
Astounding what business they got in a small mountain lake at nearly 1600m. A person releasing their unwanted pet would og to a place closer to regular car access one would think. Also that in such a shallow tiny hole with run off from snow cappped mountains a fish like this would stay alive through winter and procreate is astounding, yet this population seemed to have survived some winters, already loosing bright colouring. There where few bright red and many almost black ones. / Was so eine Spezies in einem winzigen Bergsee auf fast 1600m wohl macht? Ein Mensch der sein Aquarium wild aufloest wuerde sich doch etwas leichter ereichbares nahe bei der Autostrasse zum aussetzen suchen, sollte man meinen. Wirklich erstaunlich ist, das die dort erfolgreich zu ueberwintern und sich zu vermehren scheinen, in einem flachen Teich unter schneebedeckten Gipfeln wo das Wasser standig kalt sein muss. Aber es gibt dort sehr viele, die meissten sind fast schwarze wilde asiatische Karauschen, nur wenige im Schwarm sind Feuerrot. |
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6 comments so far...
I have had these in my aquariums --- still have their fancier, smaller relatives --- and can tell you that they don't turn black or brown.... The one above is actually turning orange. 99% of black and/or brown Goldfish turn orange as they mature. The darker the colors -- black/brown --- the younger the fish. A good portion of fry/baby Goldies are brown or black, but their genetic make-up makes it nearly impossible for them to hang on to that color... It takes a very specific diet to even give them a slim chance of keeping their all black or brown appearance. That's why adult Common Goldfish that are copper/chocolate or black are highly valued and actually prized in the aquarium/pond hobby. Probably more info. than you cared for..... ;)
The good news for them being in a high elevation lake is that they're not likely to overrun it because their not as resilient to cold as native fish species... They're also not as adapt at avoiding predators -- especially more aggressive fish species. These guys cannot "outrun" fast swimmers like pike and aren't good at avoiding stealth predators like bass either.... They're very easily caught by fishermen, too.
I had no idea real goldfish with the pointy snout are supposed to have a bright red wild type colour. I thought they are like our prussian carp, the regular Karausch or Gibel. Some of those are born with a tad more coppery tinge and only generations of human selection produce a lively coloured fish that gets dependably bright orange offspring like itself. Left to themselves in a pond, the colour vanishes from the population in a few fish generations. Of course also due to negative selection by fishing animals that see the high contrast fish best. I can tell you there where many almost inkblack fish amongst the largest in there. If they are so prized by the breeder, they might want to go and capture them then.
I had a fancy variety some years ago that was "chocolate" ... I'd had it in my aquarium for years and was thrilled to see it not reverting to orange. Then, my cat at the time decided to use the slight gap near the filter system to try and catch himself a fish. He injured the goldfish so severely/horribly, I thought for sure it was going to die -- the cat sliced it from bottom of its belly up to the top of its back. But, with treatment and a week of isolation from its tankmates, the wound started to heal..... Then, the color change started as the scales regrew over the closed wound.... Within 3mos. the fish went from being all chocolate colored, to bright orange with no hint of its former color.... The injury triggered the orange gene. The orange genes in these hybrid carp are incredibly strong.... Trust me, many a geneticist has studied and tried diff't means to alter the gene as part of selective breeding studies and failed to produce intended results. A colleague of mine did 20 generations of selective breeding to try to reliably produce brown/black Goldfish and still failed.... Out of 100K fry to reach 24" or more (young adult size) only 2 were still brown or black and of those two, when subjected to injury forcing scales to have to regenerate, 100% reverted back to their orange color after wound healing. It's downright incredibly from a genetic standpoint. But, I go into far too much detail....
As I said, I have never reared goldfish and o idea how a fully natural goldfish would look like, if there even is such a thing left in the world, perhaps they are like milk cows and house kitties, so long modified by human the nominate form is an umbrella for the breeds as much as a species and they indeed are colourful by default. But even so it would be logical outside your protective aquarium that any of them still darker and duller at reproductive age than others would be very advantaged to be allowed to pass on the genes. Also, just a thought, dark colour does not reflect warmth as much, up in a mountain lake full of snow runoff, the darkest fish would be able to make a bit better use of the sun, too.
Being orange when living on your own in a pond is generally a crappy idea, so to speak, and the habitat in controlled aquariums and in an icey cold little mountain lake with some feral fish is just not the same, and critters can adapt and morph as a species, especially if the age of vertility is low and the K-factor high.
Wht anyone breeds a choclate coloured fish from this genetic stock then is frankly beyond me. Why not get a few wild Crucian Carp and some feral goldfish to hybridize and start your new dark fancy fish from that stock to get the red out faster?
The orange color doesn't get naturally selected out because, in a large school, it actually aids in survival.... When all that orange scatters in all directions, in confuses aerial predators.... And colors doesn't mean anything to freshwater aquatic critters because they are mostly color blind. If genetics were as simple as going back to the wild stock and starting over, the chocolate/bronze/black Goldfish & Koi varieties would be common -- and a lot less prized.... But genetics isn't that simple ;)
But, I think you have to be a hobbyist to truly appreciate Goldies -- and their Koi cousins.
I have several Goldfish shots in my "Something Fishy" album if you're interested in seeing some real beauties....