WASHINGTON (AP) – The monarch butterfly fluttered one step closer to extinction Thursday, when scientists put the iconic orange-and-black insect on the endangered list because of its rapidly declining numbers.
“It’s just a devastating decline,” said Stuart Pimm, an ecologist at Duke University who was not involved in the new listing. “This is one of the most recognizable butterflies in the world.”
The International Union for Conservation of Nature added the migrating monarch butterfly for the first time to its “red list” of endangered species and categorized it as “endangered” – two steps away from extinction.
The group estimates that the population of monarch butterflies in North America has declined between 22% and 72% over 10 years, depending on the measurement method.
“What we are concerned about is the decline,” said Nick Haddad, a conservation biologist at Michigan State University. “It’s very easy to imagine how very quickly this butterfly can become even more vulnerable.”
Haddad, who was not directly involved in the listing, estimates that the population of monarch butterflies he studies in the eastern United States has declined between 85% and 95% since the 1990s.
In North America, millions of monarch butterflies perform the longest migration of any insect species known to science.
After overwintering in the mountains of central Mexico, butterflies migrate north, breeding for generations for thousands of miles. The offspring that when southern Canada begins then the trip back to Mexico at the end of the summer.
“It’s a true spectacle and arouses such awe,” said Anna Walker, a conservation biologist at the New Mexico BioPark Society, who was involved in determining the new listing.
A small group spends winters in coastal California, then spreads in the spring and summer across several states west of the Rocky Mountains. This population has seen an even more abrupt decline than the eastern monarchs, although there was a slight return last winter.
Emma Pelton of the nonprofit Xerces Society, which monitors western butterflies, said the butterflies are threatened by habitat loss and increased use of herbicides and pesticides for agriculture, as well as climate change.
“There are things people can do to help,” she said, including planting milkweed, a plant that the larvae depend on.
Non-migrating monarch butterflies in Central and South America were not 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 for the global population of tigers, which are 40% higher than the latest estimates from 2015.
The new numbers, of between 3,726 and 5,578 wild tigers worldwide, reflect better methods of counting tigers and potentially an increase in the total number, said Dale Miquelle, coordinator of the nonprofit Wildlife Conservation Society’s tiger program.
In the last decade, tiger populations have increased in Nepal, northern China and perhaps India, while tigers have disappeared completely from Cambodia, Laos and Vietnam, Miquelle said. They remain designated as threatened.
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