The 2015-2016 Monarch butterfly population census is in and the news is good: the iconic migrating insect that has become a symbol for climate change and pollinator advocacy in three countries is on the rebound with a three-fold increase in its roosting population in the past year.
The Monarch population is on the rebound with a threefold increase over last year. Here they are in Michoacán in March of 2012. Photo by Monika Maeckle
Last year the population occupied 1.13 hectares (2.8 acres) of the Oyamel forest in the mountains of Michoacán that serve as the ancestral roosting site of the storied orange and black creatures. This year: 4.01 hectares (9.9 acres) are occupied–more than triple last year’s figure, according to the Mexican government and the World Wildlife Fund. Scientists calculate the population numbers by measuring the amount of forest occupied by the Monarchs.
According to Journey North, a citizen science organization that tracks the Monarchs’ and other migrations, this year’s population numbers 200 million monarchs compared to a long-term average of 300 million and a peak of 1 billion. The organization attributed the increase to ” favorable breeding conditions in summer 2015.”
The butterflies, which migrate each fall to the Mexican mountains after a multi-generation trek through the heartland of the United State’s to Mexico, have been in a perilous decline in recent years. The 2013-2014 season in particular was frightening: the entire Monarch population occupied only .67 hectares (1.65 acres) and could have fit into a Walmart store with 30,000 square feet to spare.
The insects made a slight comeback last year, as government officials in all three countries committed to work together to save the unique natural phenomenon. Research and funding have been pouring into the cause, thanks, in part, to President Obama’s National Pollinator Strategy issued in May of 2015.
As temperatures rise and the air dries, monarchs move out of their clusters in Michoacán during the day to the delight of sanctuary visitors. Photo via Journey North
Butterfly aficionados far and wide were delighted with the news. “Great progress!! Everyone still needs to do their part to help! We can’t lose these magnificent butterflies!!” wrote Eileen Cotte on Journey North’s Facebook page.
“It certainly is reason for hope following year after year of depressing declines,” wrote Richard Knowles on the DPLEX list, an old school listserv of about 800 butterfly aficionados run by citizen science organization Monarch Watch out of the University of Kansas at Lawrence. “It almost feels like everyone can give themselves a brief pat on the back before getting back to work.”
Even Monsanto Corporation, often blamed for the butterflies decline because of the indiscriminate pesticide use that results from their genetically modified corn and soybean seed, celebrated the news: “Good news! Monarch population numbers were up in 2015. With help, they’ll keep increasing.”
We hope so. Let’s keep planting milkweed and nectar plants for all pollinators.
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