The monarch butterfly edged closer to extinction on Thursday as scientists put the iconic orange-and-black insect on the endangered species list due to its rapid decline.
“It’s just a devastating decline,” said Stuart Pimm, an ecologist at Duke University who was not involved in the new list. “It’s one of the most recognizable butterflies in the world.”
The International Union for Conservation of Nature has added the migratory monarch butterfly to its ‘red list’ of threatened species for the first time and listed it as ‘endangered’ – one step away from extinction.
The group estimates that the monarch butterfly population in North America has declined between 22% and 72% over 10 years, depending on the method of measurement.
“What worries us is the rate of decline,” said Nick Haddad, a conservation biologist at Michigan State University. “It’s very easy to imagine how quickly this butterfly could become even more endangered.”
Haddad, who was not directly involved in the listing, estimates that the monarch butterfly population he studies in the eastern United States has declined between 85% and 95% since the 1990s.
In North America, millions of monarch butterflies undertake the longest migration of any insect species known to science.
After wintering in the mountains of central Mexico, the butterflies migrate north, reproducing several generations over thousands of miles. The offspring that reach southern Canada then begin the return journey to Mexico in late summer.
“It’s a real spectacle and inspires such admiration,” said Anna Walker, a conservation biologist at the New Mexico BioPark Society, who helped determine the new list.
A smaller group spends its winters on the California coast, then disperses in the spring and summer to several states west of the Rocky Mountains. This population has declined even more precipitously than the eastern monarchs, although there has been a small bounce last winter.
Emma Pelton of the non-profit Xerces Society, which monitors butterflies in the West, said the butterflies are threatened by habitat loss and the increased use of herbicides and pesticides for agriculture, as well than by climate change.
“There are things people can do to help,” she said, including planting milkweed, a plant that caterpillars depend on.
Non-migratory monarch butterflies from Central and South America have not been designated as endangered.
The United States has not listed monarch butterflies under the Endangered Species Act, but several environmental groups believe it should be listed.
The international union also announced new estimates of the global tiger population, which are 40% higher than the most recent estimate from 2015.
The new figures, between 3,726 and 5,578 wild tigers worldwide, reflect better methods of counting tigers and, potentially, an increase in their overall numbers, said Dale Miquelle, coordinator of the Wildlife Conservation’s tiger program. Non-profit society.
Over the past decade, tiger populations have increased in Nepal, northern China and possibly India, while tigers have disappeared entirely from Cambodia, Laos and Vietnam, Miquelle said. They remain designated as endangered.