Monarchs in Mexico allow brush with fragile beauty

The monarch butterflies that spend the winter in Mexico are ones that were born in late summer and early fall in the northern U.S. and Canada, and made the long migration south to a place they had never been. (Terri Colby/Chicago Tribune/TNS)

Paula Zito, a nurse from Sarasota, Fla., takes a selfie as the butterflies surround her. (Terri Colby/Chicago Tribune/TNS)

Terri Colby/Chicago Tribune/TNS

The El Rosario butterfly reserve, a bit more than 100 miles west of Mexico City, is open November through March, and tends to be busiest on weekends.

Monarch butterfly populations have been on the decline, but swarms of the colorful insects can still be found in certain parts of Mexico. (Terri Colby/Chicago Tribune/TNS)

OCAMPO, Mexico — This is a story that must begin at the end.