“What’s Going On With Monarch Butterflies?” Resolving Seemingly Conflicting Population Reports

(SACRAMENTO, CA – Jan. 31, 2019) The yearly count of the eastern monarch butterfly population that overwinters in Mexico was released yesterday, showing a 144 percent increase over last year’s count – the highest count since 2006.

In stark comparison, the western monarch butterfly population that overwinters along the California coast declined 86 percent in 2018 compared to the previous year, with a final count of approximately 30,000 butterflies – the average population needed to avoid a complete collapse.

“The seemingly conflicting news headlines about the eastern and western monarch populations beg the question, ‘What’s going on with monarch butterflies?’ That’s precisely the question that conservationists and U.S. Fish and Wildlife Service staff are trying to answer in anticipation of a June 2019 deadline to decide whether the monarch needs to be added to the endangered species list.”

“Make no mistake, the monarch butterfly is still in grave danger. The western population is on the brink of complete collapse, and while the eastern population showed some signs of recovery in 2018, the overall trajectory of the combined North American populations is in steep decline.

“The good news is that this year’s eastern population numbers indicate that conservation efforts plus favorable weather make a winning combination. While there’s not much we can do about the weather, there’s a great deal we can do to conserve and restore monarch habitat. But we have to act fast, before it’s too late.”

• Eric Holst, Associate Vice President, Working Lands