Is this what it looks like?

[Char361979]

I'm with Stefan on this one. Tetras should be tetras. End of.

[chris-uk]

I don't disagree that a tetra hybrid is no longer a tetrataenia. If I ever have tetras they will be pure (albeit inbred) snakes. If the purpose of breeding a hybrid is to preserve tetras then the breeder would be mistaken, as they have just lost a breeding cycle that could be used to breed pure tetras.
Let's not forget that cross-breeding can occur in the wild where two sub-species cross ranges. Are the hybrids desirable as an example of either parent? No. Could they be pretty snakes? Maybe. Will hybrid offspring be able to breed? Possibly not, as hybrid animals can be sterile.
Interesting debate.

[PINJOHN]

Chris is right when he says "this is a polar subject", so there is no way a purist can be talked round, but it doesn't mean we shouldn't have a debate on it , for myself there is nothing i would like to see more than some of the mainland Europeans take on the job of strengthening the tetra bloodline with out crosses, i say this for several reasons, first it should be understood that for me this is about the European population and not tetra in general, in an earlier thread i posed the idea of using a melanistic eastern to do this job, in my view this allowed the vigor to be put back without totally mixing the genes when young are born they would be one or the other, that is expressing tetra colors or melanistic and not some intermediate form, they would be in my opinion inter grades and not hybrids, ah yes the purists will say but you have messed with the genes they may look like tetra but they are not pure, well as we don't have superman's microscopic vision and we cant actually see genes we must judge with our eyes and its our eyes that make this snake so attractive to us, please understand that i as much as anyone dont wish to see the kind of mixed up genes that you now get in so many other types of snake we all wish to keep our garters true to type BUT the san fran is a unique situation, arguably the most striking of all the thampophis highly endangered in its home range, due as much as anything to the total disinterest of the powers that be, one natural catastrophe in its tiny home range and the snake is no more, and because of federal laws there wont be any more introductions into Europe, so folks just two ways to go let the European stock die out through increasingly more sickly snakes or take measures to strengthen them by whatever means,
i think what might also help would be to give these euro snakes a specific name so that we all know where we are at, that is to say on this side of the pond there is to all intents and purposes visually at least a san fran but the pure blooded snake remain in the USA UNAVALABLE to all

[d_virginiana]

Hm... Just my guess, but the offspring would probably still be able to breed. That wouldn't be a true 'hybrid' but an intergrade (I believe that's the right term?) kind of like a coyote and a wolf.
These things do happen in nature though. As long as the offspring aren't sold as pure-bred Tetras, I can't say I'm 100% opposed to the idea. My main reason for being against crossing garter subspecies is that often the babies are 'muddy' and not desirable as pets. This means that a lot of these undesired babies end up released into the wild to alter the natural gene pool, and not just in areas where intergrades between two subspecies might naturally occur. In a situation like that where the captive bloodlines are so inbred and there is no way the offspring would be able to form a stable population if released, then idk...

I don't know for sure since they aren't even available here, but the Tetra population in Europe seems like it might headed for a dead end either way the way people are describing the inbreeding problems.

[chris-uk]

You make good sense there John. If you take an absolute purist attitude, assuming no illegal wild caught San Frans reach Europe, we would eventually inbreed the EU San Fran stock to death. So is it better to have a European strain that looks like the most beautiful garter, but isn't pure, but doesn't have inbreeding issues. Or to end up with genetically pure tetras in Europe with low survival rates and increasing problems to get them to breed in the first place.

[mb90078]

A tetra is a tetra regardless of how inbred or undesirable it is.

I would also disagree with this. I would be shocked if all wild tetras don't have some blood lines from other nearby (sub)species. As I've said before, modern humans have Neanderthal DNA (As we all know, humans did not evolve FROM neanderthals, neanderthals briefly co-existed with modern humans, and then died out). I reject the very idea of "purebred" when it comes to animals who in the wild have or have had access to interbreed with other species or sub species.

[Stefan-A]

You make good sense there John. If you take an absolute purist attitude, assuming no illegal wild caught San Frans reach Europe, we would eventually inbreed the EU San Fran stock to death. So is it better to have a European strain that looks like the most beautiful garter, but isn't pure, but doesn't have inbreeding issues. Or to end up with genetically pure tetras in Europe with low survival rates and increasing problems to get them to breed in the first place.

You know, there's a fairly simple solution to that: Increase the number of breeding pairs and apply selective forces to the offspring. Ideally, all but one or two should be culled out of a given clutch. Inbreeding is not the end of the world, unless you'll breed just anything. Quite frankly, the tetrataenia should be taken off the market for the time being.

I don't give a rat's *** if a snake looks like a tetrataenia. Either it is one, or you might as well just keep a picture of one. Any other can species can replace it, if it doesn't matter whether it is a real one or not.

[Stefan-A]

I would also disagree with this. I would be shocked if all wild tetras don't have some blood lines from other nearby (sub)species. As I've said before, modern humans have Neanderthal DNA (As we all know, humans did not evolve FROM neanderthals, neanderthals briefly co-existed with modern humans, and then died out). I reject the very idea of "purebred" when it comes to animals who in the wild have or have had access to interbreed with other species or sub species.

Yeah, let's just cross all garter species while we're at it. It doesn't matter anyway, since they all occasionally do it in the wild.

[chris-uk]

Stefan the perspective you portray is pretty narrow and idealistic. You ignore that there is a real world situation where there is a demand for San Frans, where individuals are making money from the demand, and there is no organised effort to preserve a tetrataenia as a sub species. Is the market demand for a T. sirtarlis tetrataenia, or is the market for a beautiful snake? And are the buyers willing to subject their purchases to detailed tests and examination to determine what they have is pure? In the case of San Francisco garters I fear that economics is a more significant driving force that genetics.

Lora also makes good points about integrades. It happens in the wild, nothing stopping a sirtalis breeding with a tetrataenia and producing viable offspring that carry the tetras looks. For all we know one of the early EU breeding pairs could have been a genetic intergrade.
What makes a snake a tetra? "Either it is one or it isnt"? Surely, unless we get into DNA analysis the thing that defines a snake is the way it looks and what we can observe.
What you suggest about increasing the breeding pairs and culling most of the young will actually lead to deeper inbreeding. What selective criteria would you apply to the cull? Pick the ones that look most like the parents and appear healthy? They could be carrying recessive health problems that don't express for another couple of generations, by which point you have narrowed the gene pool. Inbreeding is a problem as it elimates genetic variation which is important to combat problems caused by random mutations and the expression of adverse recessive traits. Of course if you start with perfect samples with no genetic issues you simply enhance the positive traits, at least until a random mutation destroys an copy of an essential gene.

Part of this is devil's advocate, because despite my genetics degree being 15 years old and ending up in IT rather than research, I still consider myself to be a biologist, and I can want to keep snakes that are close to wild, natural examples. It's skewed a bit by the wife's albino, but on the whole morphs really don't appeal to me. I wouldn't consider a snake that is a genetic intergrade, but phenotypically a tetrataenia to be any worse than a snake that has been bred selectively to enhance a non-natural phenotype.

Now to talk ideals :
1. Compulsory register of all tetrataenia.
2. Mandatory breeding records for individual tetrataenia, tied to a microchip implanted at birth.
3. Licensing for breeders, who are forced to exchange young snakes with other breeders, with controls to ensure that the exchanges are with different breeders each year.
4. Outlaw one breeder selling offspring from a single pair as a breeding pair.
5. Require breeding documents to be supplied with each sale.
6. Restrict ownership of tetrataenia to licensed individuals, who must inform the register of intention to breed.
...... Maybe that would give tetrataenia (as the EU stock currently exists) a half decent chance of maintaining some degree of sustainability. But it's pipe dream, enforce these sort of requirements across multiple EU member states? Not going to happen.

[RedSidedSPR]

Kinda pisses me off when people cross breed...