Angangueo, Mexico – When federal police and army soldiers moved into this remote area in a top-secret operation two weeks ago, they didn’t just put a small dent in Mexico’s crime syndicates. They also made an important contribution toward preserving the world’s biodiversity.

The targets of their raid were a dozen sawmills that were allegedly processing illegal timber. The fir and pine trees came from forests in the Monarch Butterfly Biosphere Reserve, host to one of nature’s most impressive shows.