Extirpated: A species that has become extinct in one area at least, but still exists in other area(s)
Endangered: A species whose numbers are so small it is at risk of becoming extinct or extirpated if extensive measures to protect it are not undertaken
Threatened: A species that is likely to become endangered if not protected in some way
Special Concern: A species that is not endangered or threatened but extremely uncommon or has unique or highly specific habitat requirements
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