Hi Longqi,
Sustainability of the harvest is an ongoing debate, and unfortunately we will probably not have the answer until the population crashes. However, this hasn't happened yet, and reticulated pythons are probably better suited to high levels of harvest than many think (Burmese aren't harvested from the wild anywhere.. legally
).
There is no doubt that such large harvests result in population declines, but, similar to green pythons in the other thread, I don't think collection alone will ever result in the extinction of these snakes (at least on the mainland - in the GTP example, small island populations may be at risk).
For those that think the snakes are still alive while they are skinned - I'm not saying it doesn't happen occasionally, but it doesn't happen often. If you destroy the brain of any animal then it dies instantly - fact. Sure, it would be naive to think that every blow lands correctly, but this is the exception rather than the norm. There is no incentive whatsoever to keep the snakes alive while they are being skinned - so why do it?
I'm not condoning any part of this trade; I'm merely giving an unbiased viewpoint based on correct information - which is more than I can say for PETA.
If you have the urge to sign a petition, don't jump the gun by signing one that would suspend trade and endanger the livelihoods of many poor people - sign one that calls for more research into humane methods of slaughter and capacity building for local people to slaughter animals in a way that you (not they) find more socially acceptable.
Dan