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Cold hardy cichlids?

There are already cold hardy cichlids that are endemic to to southern Uruguay and Argentina, where their natural waters often ice over. I keep Gymnogeophagus, Crenicichla and Austraoheros that easily take temps down into the 40sF.
I keep them in my pond in Milwaukee, (same latitude as Toronto) April thru Oct.
My ponds freeze solid in winter, so I need to move them in.
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Azedenkae said:
What part of 'possibly' did you not understand?

Cichlids may or may not have any preadaptations to the cold, but that doesn't mean over many generations they don't accumulate genetic elements that would allow them to survive in the cold. Same as any organism really, that's how we get all these organisms living in all sorts of environment. Most african cichlids require a (relatively) high pH but Red Forest Jewels require a (relatively) low pH. What, did you think RFJs just dropped out of the sky as is or something? Obviously not, at some point either the RFJ split from the rest and adapted to a lower pH lifestyle, or most Africans had to adapt to a higher pH lifestyle, or both had to adapt from an original different pH lifestyle. Whatever the case, at least one species had to evolve to adapt to the pH of their environment. If cichlids can evolve to survive in lower/higher pH, then they can evolve to adapt to colder temps, or other environmental factors that they are not used to.

Mutations occur all the time, tweaking genes and other genetic elements constantly, producing new varieties of genotypes. By subjecting a species to colder and colder temperatures and selecting the ones that adapt best to breed on, one will be selecting for the genetic element(s) that confers cold resistance, whether they are already there, or eventually will develope through mutations.

Of course, it is possible that it may never work, hence why I wrote 'possible', but chances actually that it would work, over many generations. It will take a lot of work, but it is entirely possible.
Click to expand...
What part of impossible in my first post did you not understand?
 
duanes said:
There are already cold hardy cichlids that are endemic to to southern Uruguay and Argentina, where their natural waters often ice over. I keep Gymnogeophagus, Crenicichla and Austraoheros that easily take temps down into the 40sF.
I keep them in my pond in Milwaukee, (same latitude as Toronto) April thru Oct.
My ponds freeze solid in winter, so I need to move them in.
068-1.jpg
Click to expand...
Even if your pond didn't freeze solid, your cichlids would not survive the winter outdoors. Have you not read about the fish kills that occur in Florida when the temperatures drop below freezing even for a couple of days?
 
While I agree that cichlids could not handle Wisconsin or New Jersey type winters outside, we often get fish kills here of our native fish such as crappies and blue gills in a harsh winter.
Many cichlids in southern South America have adapted to much lower temps than many hobbyists are aware. Latitudes where some Gymnos, some Crenicichla pikes and Chancitos reside in Uruguay and Argentina are comparable to northern Georgia, and are not considered tropical species. While Florida winters can be hard on northern South and Central American species, they would be a breeze for the cichlids of Uruguay and Argentina.
Below is a paragraph from an article called Gymnogeophagus labiatus by Marcelo Casacubierta that can be read in its entirety at the Cichlid Room Companion.
"in Uruguay (the southernmost distribution of the species) they have adapted to sub-tropical conditions, with temperatures dropping around 12C in winter. They share the habitats with other cichlids species, including G. meridionalis, a direct competitor for food, Crenicichla punctata and C. lepidota, that prey on labiatus fry."
 
There was a guppy thread like this a while back. Dig that up and in it you'll find a method to breed cold hardy fish. In short, get a genetically diverse population and cool the water until most die off. Take the survivors and breed them (and probably bring in some fresh blood to reduce inbreeding), grow them and cool the water until most die off. Repeat. Cold hardy cichlids are (to an extent) possible, the question is how long it would take. The stronger you select, the faster it will happen. What I do not expect is something that can survive being iced over.

My complaint is that cichlids are pretty strong competitors. Not sure if you'll be wanting cold hardy cichlids in the local bodies of water...because typically it is only a matter of time.
 
Well I just started a jag breeding project in one of my tanks, so maybe I'll see if I can use the "guppy method" on the fry. There's no way i can keep all the fry anyway. So whatever doesn't get sold, will get eaten, and whatever is left, gets the guppy test.


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I believe with Parachromis managuense, it will take many many generations, because it is a warm water cichlid. I had a winter power outage years back when I was working with them, and once the temp hit 60, it didn't take long for the jags to die.
You'd be better off starting with a cichlid that is already a bit cool hardy such as a Herichthys cyanoguttatus, beani, or Geophagus braziliensus, some of the Uruguayans.
Below is a pic from today, of my Red Ceibal grow out tank.
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And my Gymno, Crenicichla tank
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Interesting concept, but here is why it's somewhat perturbing.


First, being adapted to cold involves changes in numerous features in a fish's anatomy including the endocrine system, respiratory system, circulatory system, digestive system, and reproductive system, just to name a few.

Second, evolution does not work by making a series of changes in everything. The changes are random. Some are beneficial, but most aren't. Just because some fish survive out of a batch does not mean anything more than they had 'some' advantage over the ones that died. The advantage may have nothing to do with being better adapted to cold, but simply being better adapted to finding food or pure dumb luck. The advantage itself might 'help' them at 65 degrees but be a horrible feature at 50 degrees. In evolution there are uncounted number of evolutionary branches that became extinct.

Third, once all these changes had finally happened, after let's say, 20,000 generations, I'm thinking that they would no longer be cichlids. They would lose the features that define the cichlid family, thus we couldn't call them that anymore.


Here is the description that defines a Cichlid:
Cichlids share a single key trait: the fusion of the lower pharyngeal bones into a single tooth-bearing structure. A complex set of muscles allows the upper and lower pharyngeal bones to be used as a second set of jaws for processing food, allowing a division of labor between the "true jaws" (mandibles) and the "pharyngeal jaws". Cichlids are efficient feeders that capture and process a very wide variety of food items. This is assumed to be one reason why they are so diverse.[SUP][4][/SUP] Cichlids vary in body shape, ranging from compressed and disc-shaped (such as Symphysodon), to triangular (such as Pterophyllum), to elongate and cylindrical (such as Crenicichla).[SUP][12][/SUP]
The features that distinguish them from the other Labroidei include:[SUP][13][/SUP]

  • A single nostril on each side of the forehead, instead of two.
  • No bony shelf below the orbit of the eye.
  • Division of the lateral line organ into two sections, one on the upper half of the flank and a second along the midline of the flank from about halfway along the body to the base of the tail (except for genera Teleogramma and Gobiocichla).
  • A distinctively shaped otolith.
  • The small intestine's left-side exit from the stomach instead of its right side as in other Labroidei.
There is no reason to believe that any (much less all) of these features would persist as the cichlids evolve to adapt to cold water. In fact, if any feature were lost, they would no longer be a cichlid. This would require us to kill any spawn that lacked any of these feartures plus to kill off any spawn had a new distinctive feature.
 
duanes said:
While I agree that cichlids could not handle Wisconsin or New Jersey type winters outside, we often get fish kills here of our native fish such as crappies and blue gills in a harsh winter.
Many cichlids in southern South America have adapted to much lower temps than many hobbyists are aware. Latitudes where some Gymnos, some Crenicichla pikes and Chancitos reside in Uruguay and Argentina are comparable to northern Georgia, and are not considered tropical species. While Florida winters can be hard on northern South and Central American species, they would be a breeze for the cichlids of Uruguay and Argentina.
Below is a paragraph from an article called Gymnogeophagus labiatus by Marcelo Casacubierta that can be read in its entirety at the Cichlid Room Companion.
"in Uruguay (the southernmost distribution of the species) they have adapted to sub-tropical conditions, with temperatures dropping around 12C in winter. They share the habitats with other cichlids species, including G. meridionalis, a direct competitor for food, Crenicichla punctata and C. lepidota, that prey on labiatus fry."
Click to expand...

12 C = 53 F. Water temperatures in the northern US get down to the 30s. A 20 degree difference is huge.
 
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