Science Saturday III: Protecting the Monarch

Wildlife officials in Mexico, the U.S. and Canada have agreed to work together to protect the Monarch butterfly, which makes a spectacular migration every year from Canada to Mexico.

Under the agreement, the Trilateral Monarch Butterfly Sister Protected Area Network will designate 13 wildlife preserves as protected areas and develop international projects to preserve and restore breeding, migration and winter habitat for the orange and black butterflies.

Every autumn, millions of monarchs leave eastern Canada and the United States and fly distances of 2,800 miles (4,500 kilometers) and more to the oyamel fir forests of Mexico's Sierra Madre Mountains for the winter. Monarchs west of the Rocky Mountains migrate south to eucalyptus groves in southern California.

The informal agreement will include sharing information about ways to preserve the habitat and migratory pathways of the butterflies, according to Donita Cotter, a spokeswoman for the U.S. Fish and Wildlife Service.

Best of all, it will not require any legislation.

Monarch researcher and ecologist Dr. Lincoln Brower of Sweet Briar College in Virginia said that the agreement was a good symbolic statement, but will do little to preserve the butterflies unless stronger action is also taken to stop logging in Mexico and to change farming practices in the U.S. that are destroying the plants the butterflies rely on.

Illegal loggers have been destroying the trees in Mexico's Monarch Butterfly Biosphere Reserve, while development is threatening the California eucalyptus groves. Brower said there is evidence that heavy use of weedkillers is wiping out the milkweed plant, which is the only thing that Monarch caterpillars will eat.