The Tiger Creek Wildlife Refuge (http://www.tigercreek.com/) is run by the Tiger Missing Link Foundation (http://www.tigerlink.org/). That foundation is a non-profit 501(c)(3) foundation (meaning your donations would be tax deductible). It is a legitimate charity.
However, Charity Navigator, an independent charity ranking agency, has given it 1 star out of 4. This is because less than half the money you donate will end up helping tigers. The rest goes to fundraising costs and salaries.
In short, this is a legitimate charity, but more than half of your donation will go to admin costs.
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