What makes these species rare to begin with? And why have they survived? On the one hand, ecological theory predicts that rarity makes a species vulnerable to catastrophes. On the other hand, rare, old-growth associated species do occur in west side forests, which have a long history of natural catastrophic disturbances. If we can understand something about how rare species persisted up to the present day, we may learn something about how to manage for their persistence in the future. Understanding mechanisms of rarity is vital to developing multispecies approaches to the survey and manage list.

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