Butterfly populations declining rapidly in U.S. with 22% disappearing in 2 decades, study finds
Butterflies are known for their beauty and important role in pollination. Disappeared from the American landscape At an amazing speed. comprehensive studypublished Thursday in the Journal of Science, found that between 2000 and 2020, 22% of butterflies in the United States disappeared.
New research There is a clear warning about the potential future of these precious insects.
“In 20 years, the loss of one out of every five butterflies in 20 years should be a big wake-up call,” said Dr. Eliza Grames, assistant professor of biological sciences and co-author of study at Binghamton University. “These declines have not stopped.”
Although butterflies are the most widely monitored insect population in the United States, most past studies have been restricted by geographically or focused on specific species, the study’s press release said. The researchers behind the scientific research used data from more than 12.6 million butterflies from over 342 human species, extracted from 76,000 surveys in 35 national monitoring programs.
Funded by the U.S. Geological Survey, its authors say, the study is the first to integrate such a large data set. The results show that 33% of butterfly species have experienced a large population decline over the past two decades, with 107 of the 342 species losing more than half of the population, and 22 of them falling by more than 90%. Meanwhile, only 3% of species show an increase in population.
One of the most eye-catching examples is Monarch Butterfly. December 2024, American Fish and Wildlife Services The monarch was proposed under the Endangered Species Act, saying that the eastern population of the species has dropped by about 80%, and the western population has dropped by more than 95% since the 1980s.
The species has Designated endangered species By the International Union for Conservation of Nature in 2022.
Ultimately, the decline in butterflies is part of a global trend in insect population loss, with insects falling about 1-2% each year, the study’s authors said.
Butterflies play a vital role in ecosystems, pollinating flowers, crops and other plants. Their decline may have profound effects on plant reproduction and ecosystem health.
According to scientific research, habitat loss, climate change and the use of pesticides are driving its decline. Temperature rise and climate change threatens butterfly populations, reduces food sources and increases habitat stress by disrupting the breeding cycle. The study said pesticides have been identified as the main cause of butterfly decline and can be addressed through policy interventions such as limiting harmful insecticides, promoting pest management and encouraging diversified planting.
Despite the decline, individuals can still take steps to help the butterfly population recover, Gram said.
“One of the really positive messages about insect conservation is that what we do in the backyard actually makes a difference,” she said.
She recommends allowing a portion of the yard to grow with native plants, reducing pesticide use, and creating habitats such as small brush piles of insects. “Even simple actions, such as leaving a wildflower or species supporting pollinators, can provide important resources for butterflies and other insects.”
On a larger scale, conservation efforts, including habitat conservation and climate adaptation strategies, are also critical to protecting vulnerable species and ensuring sustained environmental change.
