Answer and Explanation:
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However, we can say that otters only live in ecosystems with clean water and a large amount of healthy fish. In this case, studying the ponds where the otters live and the places where they do not want to settle, shows scientists the ecosystems that are healthy and preserved and those that are not.
These information must be given in the article to convince readers that the study of otters can inform scientists about the health of ecosystems.