Is this what it looks like?

[Stefan-A]

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.

It doesn't matter one bit what the demand is for, or what people will do in the name of economics. You know as well as I do, that the market doesn't decide what should or shouldn't be done.

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.

Except the fact that for example tetra x infernalis hybrids don't generally end up looking like tetras.

What you suggest about increasing the breeding pairs and culling most of the young will actually lead to deeper inbreeding.

Actually, it will address the problems associated with inbreeding, not inbreeding itself. Inbreeding is inescapable. If it leads to the extinction of the captive population, so be it.

What selective criteria would you apply to the cull?

Make a list of the problems tetrataenia suffers from due to inbreeding, and you have your criteria.

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.

What gene pool? There's no widening a gene pool that can be traced back to one possibly related pair, except through increased numbers to increase variation and selection to weed out the ones that shouldn't reproduce. That's a process that occurs in nature, every time a species colonizes a new area and it always starts with massive inbreeding and the samples are never perfect.

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.

Talking ideals:
1. Eradication of the entire captive (in)bred population of tetrataenia in Europe.
2. CITES Appendix I-listing the subspecies.

[chris-uk]

It doesn't matter one bit what the demand is for, or what people will do in the name of economics. You know as well as I do, that the market doesn't decide what should or shouldn't be done.

I disagree somewhat, the market itself doesn't decide what should be done. It's people who don't share the same ethics as you, that own pairs of tetras and realise that there is a market for them and that they could be making money - it's the individuals that own San Frans that will decide which snakes they are willing to breed from.

Except the fact that for example tetra x infernalis hybrids don't generally end up looking like tetras.

I have not evidence to either agree or disagree with this statement.

Actually, it will address the problems associated with inbreeding, not inbreeding itself. Inbreeding is inescapable. If it leads to the extinction of the captive population, so be it.

It wouldn't actually address the problems associated with inbreeding, but it would extend the number of generations where inbreeding is viable, eventually inbreeding will kill off the captive population. Inbreeding is a problem, for all the reasons that Lora and myself have mentioned already. There may be two solutions to the inbreeding issues the EU population has, either new blood (illegal) or genetic engineering (expensive and therefore not viable). It may also be that the EU snakes are so inbred already that new blood wouldn't make a lot of difference.

Make a list of the problems tetrataenia suffers from due to inbreeding, and you have your criteria.


What gene pool? There's no widening a gene pool that can be traced back to one possibly related pair, except through increased numbers to increase variation and selection to weed out the ones that shouldn't reproduce. That's a process that occurs in nature, every time a species colonizes a new area and it always starts with massive inbreeding and the samples are never perfect.

There is still a gene pool for captive EU San Frans, the size of the gene pool is the issue because you are correct that you can't widen the gene pool without increasing variation. Selection is not going to widen the gene pool, as breeding from existing tetras does not increase variation, at best it increases the number of viable pairs available for breeding that don't have any visible problems. However, culling a snake that doesn't fit the visual criteria (I say visual because I don't imagine anyone would subject baby tetras to any genetic or biochem test) actually narrows the gene pool because that snake may have been carrying the last copy of a useful gene, as well as varying from the criteria.
This is the crux of the discussion, increasing the gene pool - there is no legal way to do it and maintain a pure tetra, so the alternative of using a related subspecies would be the only legal way to introduce new genes into the pool. As you successfully argued, this would then mean you no longer have a tetra, but an intergrade that looks like a tetra.

Talking ideals:
1. Eradication of the entire captive (in)bred population of tetrataenia in Europe.
2. CITES Appendix I-listing the subspecies.

My view as to what should be done with tetras has shifted slightly. I had a naive thought that the somehow the EU population was somehow providing a safety net against the extinction of wild tetras, unfortunately I think I'm wrong there. My lofty ideal of owning some tetras, which I would have sourced from different breeders to try to put together pairs that are more distantly related, wouldn't contribute one bit to preserving a species that is beautiful enough to warrant preserving.

So, my current thinking agrees with both of your ideals, neither of which I'm in a position to influence. And I'll got back to the first paragraph of this post - while there are still people in Europe who want to pay significant amounts for pretty looking snakes, there will be people in Europe that breed them (some with good knowledge and understanding of the issues, others that don't care about anything other than selling them and turning their pair of tetras into a profit, we won't get the latter type on this forum).

So I think I've almost put the final nail in the coffin of tetra ownership in the Chris/Char household, we'll be looking for other garter species to own, appreciate, and maybe study.

[Stefan-A]

I have not evidence to either agree or disagree with this statement.

Here's what you can expect:




I'm using these pictures without having asked for the owner's permission.



And to jog everyone's memory, this is what a tetrataenia looks like: