To Save Some Species, Zoos Must Let Others Die

As the number of species at risk of extinction soars, zoos are
increasingly being called upon to rescue and sustain animals, and not
just for marquee breeds like pandas and rhinos but also for all manner
of mammals, frogs, birds and insects whose populations are suddenly
crashing. 

To conserve animals effectively, however, zoo officials have concluded
that they must winnow species in their care and devote more resources to
a chosen few. The result is that zookeepers, usually animal lovers to
the core, are increasingly being pressed into making cold calculations
about which animals are the most crucial to save. Some days, the burden
feels less like Noah building an ark and more like Schindler making a
list. 

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