The migration is an inherited trait; no butterfly lives to make the round-trip. The millions of orange-and-black butterflies cluster so densely on tree boughs in the reserve that researchers count them by the number of acres they cover.
Elvira Quesada said officials are trying the same approach in the Michoacan town of Cheran, where a conflict between illegal loggers and local residents has resulted in about a dozen deaths in recent months. Residents of Cheran put up roadblocks and demanded the army be sent in to protect them from logging gangs.
It is also being tried in the Chimalapas region on the border between the southern states of Oaxaca and Chiapas, where Indian communities are fighting over land and forest resources.
The measures could be used in "land conflicts, environmental and law enforcement disputes, where the key to the solution is preserving natural resources," Elvira Quesada said.
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