BBC climate and science
Population of butterflies in the United States have decreased by more than fifth in a distance of two decades, according to a new study.
The numbers fell by 22% between 2000 and 2020, according to a study by the University of Binghamton, New York.
A third of the species recorded a serious fall, and some, like Julia’s skipper, lost more than 90% of their population.
However, researchers say butterflies may be able to recover if urgent preservation measures are taken.
Study published in magazine science Measured butterfly “abundance” – number of individual individuals within a particular area. He analyzed 12.6 million butterfly visions from 76,000 surveys in 35 tracking programs.
This included data from the scientific programs of citizens such as the fourth July of the North American Association of Butterflies.
Using statistical models, they estimated the population trends for 342 species.
The results showed that 33% were in a significant decline, and many showed extreme losses – 107 species dropped by more than 50%.
“While the results aligned with global trends, seeing the scope of falling on such a large spatial level was sobering up,” said Prof. Eliza Grames, Assistant Professor of Biological Sciences at Binghamton University.
Some of the most commonly affected species include Florida White, Hermes Copper, Orange Orange, Mitchell’s Satyr and West Virginia White, and all in abundance have decreased by more than 98% in the US.
The lady of the West Coast, once the usual butterfly in the yard, decreased by 80%, raising the alarm while even this very adaptable species of fighting.
“It’s alarming because it suggests that even usual butterflies are not sure,” Prof Grames said.
Loss of habitat, pesticides and climate change are the key causes of this fall, according to researchers.
Butterflies are key polls, support plants and crops. Experts say their fall could disrupt food production and the entire ecosystem.
They also serve as indicators of environmental health – when the numbers of butterflies fall, signals problems with other species.
Southwest now affected the most
Types are the hardest to decline in the southwest of the US, one of the hottest and the smallest regions, researchers say. They believe that drought can be a major contribution to these losses.
“The drought is a double threat – it directly harms butterflies and affects their food and host plants,” Prof Grames explained.
The results could help start important exertion of preservation, such as priority of species for the International Nature Conservation Association (IUCN) of the Red List of endangered types and protection of endangered species.
Despite the fall, there is hope for recovery.
“Butterflies can recover quickly because they have short creation. Small actions such as planting wild flowers, reducing the use of pesticides or even leaving part of the yard intact can significantly improve their chances,” said Prof. Grames.
She also emphasized the need for government action.
“Insects are fundamental to life on Earth and we need actions of conservation and policies that support insects.”
