Spring is the time of the great monarch migration when the butterflies leave their wintering grounds in Mexico and head north to Canada. As we have been saying for quite some time, fewer and fewer butterflies have been making the trek each year. Twenty years ago, a billion monarchs swarmed the winter site in Mexico. In 2013, the number was down to 33 million.
We have done a number of stories about the sad state of the monarch butterfly and how their numbers have dropped from a billion to only 33 million as of a couple of years ago. Biologists in the U.S. have been trying to restore the summer habitat of the butterflies by urging the planting of milkweed, which is the primary host plants for monarch butterfly caterpillars.