By Paul James
At a press conference in Mexico City last January, scientists cheered when the official eastern monarch butterfly population was announced. And with good reason: The numbers were an impressive 144% increase over the previous year, and the highest recorded since 2006. At the same time, however, it was announced that the California western monarch population had declined by a stunning 86%. So what gives?
Most scientists agree that the increase is likely due to favorable weather conditions during the spring and summer breeding seasons and the fall migration. But they warn that one good year, while worthy of celebration, doesn’t mean the population will continue to rise.
“This reprieve from bad news on monarchs is a thank-you from the butterflies to all the people who planted native milkweeds,” said Tierra Curry, a senior scientist at the Center for Biological Diversity. “But one good weather year won’t save the monarch in the long run, and more protections are needed for this migratory wonder and its summer and winter habitats.”
The population figure of the eastern monarch – the one that travels through Oklahoma – is based on how many acres of trees the overwintering butterflies inhabit in the mountain forests of Mexico. In 2018 that number was 14.9 acres; in 2013 it was a mere 1.7 acres. The target for monarch recovery is a sustained 15 acres, but if the past 20 years is any indicator, that may be an elusive goal at best.
But still, there’s hope. Here in Oklahoma, interest in creating and expanding monarch habitat is at an all-time high. Sales of milkweed have skyrocketed, and more gardeners than ever are focusing on plants that attract adult monarchs as well, who need nectar and pollen to survive. (To learn more about how to help ensure thriving monarch migrations for generations to come, consider joining the Oklahoma Monarch and Pollinator Collaborative. For details, go to www.okiesformonarchs.org.)
And every other state in the monarchs’ migratory pathway is doing likewise. So to the extent that these efforts can offset the damage done by pesticides and habitat loss, I’m hopeful that the recovery seen in 2018 is indeed sustainable. After all, I can’t imagine a world without monarch butterflies, and I’m pretty sure you share my sentiment.
Note: Incidentally, the dramatic decline in California’s monarch population – down from 1.2 million two decades ago to a mere 30,000 now — is being attributed in large part to wildfires and the resulting loss of habitat, but pesticide use remains a problem as well. The current numbers mean that the western monarch butterfly, which overwinters in coastal California rather than central Mexico, is on the verge of extinction.
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