Anyone that has grown up in South Florida has seen how many exotic species can absolutely thrive.
The fact that some rather plastic species survive does not imply that any species that is introduced will survive. There are lots of species of herps (and other vertebrates) that have been released in southern Florida that have failed to survive.
Eastern Indigos are dying out for several reasons. Until those reasons are clearly known, releasing captive bred babies dooms them to the same fate.
I've heard this gene pool contamination issue raised before. Ironically, Florida game officials have bred Texas cougars with native Florida panthers to supposedly add some genetic diversity to a relict population that is supposedly showing inbreeding traits. If they are using this argument against reptile introduction, they certainly do a big flip-flop when it comes to a more "glamourous" mammal.
It has little to do with the glamor of the species. The FL panther is so critically endangered that it is on the verge of extinction. In a last ditch effort to preserve the population, people felt it was worth the risk of contamination to bolster the gene pool with some outside blood. But that won't fix the problem. There isn't enough room in south FL for people and panthers and the little bit of room that is left for panthers is being destroyed from the outside.
I would love to see the eastern indigo succesfully become reestablished. But frankly, there are probably enough indigos in the wild to do this on their own if the causes of their decline are removed.
Reintroductions just don't work. Man, it would be great if they did, but they almost never do. That is why agencies are disinclined to seek that solution to the problem. They tend to choose the approach of protecting what is left and trying to mitigate the conditions that are leading to their inability to increase in number.
And if, by some chance, the appropriate agencies decided that a massive captive bred reintroduction was necessary, there are plenty of preapproved zoos, etc., that already have agreements with the agencies to provide good stock with known provenance. Furthermore, it is much easier for wildlife agencies to monitor the fate of cb babies that came from zoos, etc.
The captive population in the hands of private breeders does not have any sort of acceptible provenance and the wildlife agencies are not going to participate in any program that is funded, in part, by the sale of listed species. I think the hobbyist may have a chance to participate in such a program (again, in the slim chance that it would ever be established) only by supplementing the bloodlines available to the breeding institutions (occasional breeder loans to zoos).
Donating money to preserve/restore habitat is a much more direct way for the hobbyist to impact indigo survival, IMHO.
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Chris Harrison