In one of nature’s greatest marvels, monarch butterflies are slowly heading to their summer grounds now, as far north as Canada.
Probably North America’s best-known butterfly, the striking orange-and-black monarch is the continent’s only butterfly that flies south in the fall, overwinters in a semitropical region, and returns in the spring.
The long-migration feat is even more amazing because the monarchs that head south each fall are about four generations descended from the ones that left Mexico the previous spring. So, none of those fluttering their way up north now will make the round trip. They will pass the instinct to migrate to succeeding generations.
Millions of monarchs east of the Rocky Mountains spend the winter in a small area of Central Mexico’s mountains. As spring approaches, they head north. A large segment of them sojourns in Georgia long enough to produce a new generation to continue the northern trek.
Spotting a monarch in Georgia and elsewhere, however, has become more difficult. Some experts fear that monarchs’ migration could be crashing because of serious population declines due to habitat loss, severe droughts, climate change and other problems.
“We’re very worried,” said Trecia Neal, a Fernbank Science Center biologist who is with Monarchs Across Georgia.
Speaking recently at an Atlanta Audubon Society meeting, she noted that the number of monarchs overwintering in Mexico has declined by as much as 90 percent since the 1990s.
Probably the single biggest reason for this is a scarcity of milkweeds, 22 species of which grow in Georgia. Milkweeds are vital to monarchs because they are the only plants on which their caterpillars feed.
The reasons for the lack of milkweeds are varied — misuse of pesticides, development and other factors. Milkweeds also are regarded by many farmers, gardeners, homeowners and highway crews as nuisance plants, and they mow them or spray them with herbicides.
But Neal, MAG and others want to change that. They are asking everyone to protect and plant more native milkweeds. “More milkweed will be a key to monarch recovery,” Neal said.
In the sky: The moon will be full May 14 — the "Planting Moon," as the Cherokee peoples called this month's full moon — according to David Dundee, Tellus Science Museum astronomer. Mercury is low in the west just after dark. Venus rises out of the east about two hours before sunrise. Mars rises out of the east just before sunset and will appear near the moon Saturday night and Sunday night. Jupiter is low in the southwest at dusk and sets in the west a few hours later. Saturn rises out of the east at sunset and will appear near the moon May 14.
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