The monarch butterfly was removed from the endangered species list this week in an unusual reversal just over a year after the iconic orange-and-black migratory butterfly was put on the not-sought-after list, as scientists reassess the species’ population.
The butterfly was removed from the endangered species list this week, after it debuted on the list last July following a pessimistic report by the International Union for the Conservation of Nature, which cited habitat destruction, deforestation and urban development for its dwindling numbers, Science and National Geographic reported this week.
Last month, University of Georgia ecologist Andy Davis petitioned the IUCN to have the status of the butterfly downgraded to “vulnerable to extinction,” according to the organization, which stated the species could even be downgraded one more level to “near threatened” status.
Davis filed the petition after finding that while monarch populations had declined in some areas in North America, they had increased in others, including by roughly 1.36% in their breeding grounds.
Last week, the IUCN admitted its models were “too precautionary,” lead researcher Anna Walker told National Geographic, relying instead on a previous model that found the species reached an inflection point in 2014 when its steep fall gave way to a slower decline.
The IUCN will publish its decision in December.
Not all researchers, however, believe the new designation is beneficial. University of Wisconsin conservation biologist Karen Oberhauser told Nature that the classification of “endangered” might still be necessary due to risks from drought, and that the species’ population is “not sustainable.”
The IUCN found last July that a multitude of factors led to the monarch butterfly’s declining population, primarily due to habitat loss from deforestation and logging, as well as urban sprawl across the monarch’s traditional wintering grounds in the U.S. and Canada. The IUCN estimated the population fell between 23% and 72% over the past decade, and by roughly 99.9% from roughly 10 million in the 1980s to under 2,000 last year. The organization cited changing weather patterns—including drought, high temperatures and increased wildfires—have brought the crucial pollinator closer to extinction. It also attributed the species’ falling numbers to a proliferation of agricultural pesticides that have been found to kill both monarchs and the milkweed that monarch caterpillars eat exclusively.
Monarch Butterflies Added To Endangered List (Forbes)