9953
Until recently , beavers were wrongly considered non-native pests , and these native mammals and their dams are still being removed by wildlife managers in the Sierra Nevada despite evidence of their beneficial effects on biodiversity for fish and other species in mountain wetland ecosystems .
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Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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