Its a tough subject, by try to nudge the boundaries, these are not critically endangered sumatran or amur tigers etc, these are probably inbred (at some point) mongrel tigers. Yes they are tigers none the less but so are all the white, tabby and strawberry ones, again pointless breeding them other then for the appeal of the kind of zoo visiter that remembers / expects chimps tea parties etc.
They stuffed up big time, and thanks to their webcam, on an international stage, hopefully they will learn from it next time ( open remark to Noahs ark, please don't breed from these tigers, hold them gain experience from them and in the 12 - 18 months get a worthwhile sub-species!!)