Number of monarch butterflies hibernating in Mexico plunged 26% last year — and climate change and forest degradation are to blame
BY LI COHEN FEBRUARY 27, 2021 / 12:40 PM / CBS NEWS
Monarch butterflies provide a unique spectacle every fall as they migrate to Mexico to hibernate for the winter. But now, that migration is at risk, as logging and climate change have taken a toll on the areas where these butterflies rest.
According to a new report by the World Wildlife Fund and Mexico's government, the monarch population present for hibernation in Mexico plunged by 26% in December compared to the same month in 2019.
In 2019, the monarchs occupied 2.83 hectares, nearly 7 acres, in their hibernation forests in Mexico. After their latest migration in 2020, however, they occupied just 2.1 hectares, roughly 5.1 acres.
Jorge Rickards, director general of WWF-Mexico, said the data shows that the migratory process of monarchs is at risk, and urged governments and scientists to work on addressing the issue.
In the U.S., the monarch butterfly is approaching endangered status. In December, the U.S. Fish and Wildlife Service said that listing the butterfly species as endangered or threatened is "warranted" under the Endangered Species Act, but that there were other species that were higher priority to be listed. The FWS said it will review the status of monarch butterflies annually.
"Monarch butterflies show us how individual work, in this case, migration, can become an exceptional collaborative exercise, when all these migrants gather in the forests to hibernate together and buffer the climate," Rickards said in a statement.
The decline is likely related to the decreasing forest area in the Monarch Butterfly Biosphere Reserve, where the majority of hibernation colonies are recorded. Friday's report found that in the year leading up to the most recent migration, the forest lost four times more trees than it did the year prior.
Read more from the source.