Perhaps I can shed some light on exactly one such program taking place with 20 miles of my front door. I live on Vancouver Island, and there is a species of marmot (Vancouver Island Marmot) that is very endangered that they are trying to repopulate. The Calgary Zoo is heading up the breeding program, and the parent stock are wild caught marmots, not second and third generation animals. Also, the breeding project is very secluded with minimal human contact. There are no antibiotics or other medications used on the breeding stock or the pups born. Once the marmots are weaned, they are released back into their native area, the Beaufort Range. Please note, there is no line breeding involved here.
The same I don't believe holds true for the corn snakes in question that are being released. Bred specifically for homogenous morphs and heterozygous morphs, these snakes carry a wider ranging possibility in genetic diversity and are being released outside of a controlled environment. These snakes are free to migrate as far as need be to establish their own territory and should they survive, have the ability to introduce new genes where those genes may not be present, therefore upsetting the natural genetic make up of the local population.
What I have not seen here is one single arguement that demonstrates a beneficial impact on the wild stock. Instead, there has been a lot of "what harm can it do?" The answer is simple. Who knows??? We may not see an impact in our generation or our childrens generation, but as these genetics spread, at some point in time they may begin to surface. I don't think it is worth the risk. I think we have a responsibilty to excercise ethical stewardship towards our natural resourses, especially when it comes to wildlife. Whatever others have done in the past...highways, bulldozing..whatever...doesn't really make this right simply based on "well..it's not the worse thing that could happen".
Again, this is just my opinion, I hold fast to it, just as Rich is holding fast to his. We are all entitled our opinions.
Well, would you say that genetic diversity in local populations is good or bad for the species? If you consider it as "good", then does it matter where this diversity comes from? Does it really matter whether that gene came from one or more animals that it spontaneously developed within in the wild, or from one or more animals released from captivity carrying that gene?
How many times have you heard people say that they wanted to get "new blood" for their breeding projects? Now why do you suppose they would want to do that? Is getting "new blood" beneficial in some way to local populations, whether in captivity or in the wild?
As far as I know, no one has developed a method to FORCE mutations within their captive populations. This is a natural event that takes place regardless of our efforts to influence that sort of outcome.
So when a mutation takes place, it is a NATURAL event, which is neither good nor bad until circumstances prove whether it helps or hinders the survival of the individual that exhibits that mutated state. Obviously if it helps, then it was a positive step for the species, and those surviving individuals will be able to pass this mutation on to subsequent generations. If it hinders, then nature tends to weed those failed experiments out pretty quickly, as those failures will generally NOT be passing on what by every right could be considered as a "lethal gene". In other words, if by having this gene expressed gets an individual killed off more quickly then those animals NOT having that gene, it is a self limiting mechanism to get that mutation expunged from the population rapidly.
So, a mutation that shows up in a captive population that is then dispersed into the wild is really no different from the mechanism that produces it in the animals on just the other side of the door. In captivity, it is possible to keep alive mutations that would not be beneficial in the wild, but regardless, once that gene pool has been exposed to the wild, what really would make a difference in outcome at this point? Maybe more individuals in a local population would be carrying that gene, but if in numbers the mutation got a foothold in the population and proved then to be beneficial to the survival of the species, then wouldn't that be an overall benefit to the species, regardless of how it came about?
If, instead, every one of those phenotypes got picked off rapidly by predators or otherwise proved to be a detriment to the species, wouldn't this self regulating mechanism that would eventually eliminate that gene from being carried forward into future generations limit and eventually eliminate any such negative consequences? For instance, a gene that makes a corn snake more visible to owls and therefore quickly picked up by that predator, would make this gene self limiting by that fact.
My belief is that all genetic mutations are simply experiments in opportunity for the organism that has them. For instance, anerythrism proved to be a beneficial color mutation for the corn snake in that it made the animal blend in better when laying on the roads that were generally asphalt with pieces of limestone mixed in. Had this mutation taken place at a time before such roads were used, or in an area of different road construction, would the same results have been reached? For instance, had the mutation taken place on a barrier island with only white sandy soils with NO paved roads, how well would a mostly black and gray snake have fared there? Since mutations are basically blind of the environment when they originate spontaneously, but only propagated over generations in increasing populations if successful, certainly nature may have TRIED that particular experiment, but failed.
As for the genes coming from captive hatched pools, rather than from being a spontaneous development in the wild, what really is the difference as far as that species is concerned? And in fact, introducing new genes into areas where they did not originate spontaneously in the native population, yet provide more opportunities for the species to try the mutation experiment in more environments would have to be considered as being beneficial to the species in general. It is providing more OPPORTUNITIES for the species to try out a mutation to see if it will be successful in other environments. Isn't that what spontaneous mutations are doing anyway?