I agree with gsarchie about how many you collect. It would be a shame to lose the trait from the wild.

I would also suggest that any females you collect be immature and grow them up to breeding size. I met a guy here in Georgia who had a WC Copperhead that he used for exhibits and eductaion. He said that it had not been with another snake for 5 years and yet it gave birth to a single offspring. So, sperm retention is obviously an issue if you were to use a sexually mature animal. You couldn't really be certain the offspring were a direct decendant of the pairing, other then the maternal aspect of course.