Forests lose their wings

MONARCH BUTTERFLIES } BUFFETED BY WINDS OF CHANGE

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Like most insects, butterflies are not terribly good fliers.

They often rely on wind currents to help them to their destinations. As rising temperatures affect forests, vegetation and Earth's massive wind systems, the monarch butterfly is finding itself caught in the crosshairs.

It isn't the only one, but it is a good bellwether of what is unfolding in the world of migratory insects, because few species have been studied so extensively, for so long. The wealth of data gathered on these lepidopterans since the 1950s is giving researchers unique insight into how hard these butterflies have been hit.

There was a time when they arrived in California in such large numbers, one could hear them congregate.