It's a real Catch-22 on this one.
As many of the world's species are becoming dangerously close to extinction, zoos are shouldering some of the burden.
Many zoos are sheltering animals for breeding purposes but they've had to make tough, and somewhat harsh decisions about which animals get to live.
The St. Louis Zoo is feeling this hardship all too well.
The zoo is currently breeding the Madagascar native ring tailed lemur and the program is currently flourishing.
But for the lion tailed macaque, a species the zoo has had since 1958, there is the beginning of the end. American zoos began phasing out the macaque in the 1990s, and they may begin to give up on the animal.
There are only about 4,000 macaques in the wild.
Critics believe that not enough zoos are changing their ideologies, at least not fast enough. In the beginning, American zoos were for entertainment but now, many are switching to conservation.
Sadly, it may be too late to save some of the creatures Americans have gotten to know.
Tags: america, animals, conservation, endangered species, zoo