"What these biologists did was wrong," said Mills. "They corrupted the integrity of the data." But despite the controversial incident, Mills argues that the results of the survey are scientifically reliable.

He noted that his laboratory analyzed 782 hair samples in 1999 and 1,017 samples in 2000, using a scientifically accepted method for distinguishing cat species, and only seven of those samples were mislabeled and therefore invalid.

"I'm still optimistic that the roots of the National Lynx Survey are solid," he said.

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