GOLDEN VALLEY, Minn. — When millions of Monarch butterflies land on a tree, you can barely see the tree. It's even more impossible to count the monarchs on the trees!
Scientists actually count the number of hectares of trees covered by Monarchs and then multiply by 100 million, rather than count individual Monarchs.
The Monarch population is decreasing little by little. In 2014, the number was as low as just 67 million.
West of the Rocky Mountains, the Monarch population is down by 86 percent.
Three or four decades ago, the estimation on the number of Monarchs in this population was around 500 to 600 million butterflies.
This year, we finally reached 600 million Monarchs for the first time in 12 years.
Hopefully, when scientists count next year, there will be even more Monarchs.
Click here for more explanation on the Monarch population count from monarchwatch.org.
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