SAN FRANCISCO (AP) – The number of western monarch butterflies wintering along the California coast has dropped precipitously to an all-time high, putting the orange and black insects close to extinction, researchers said on Tuesday.
An annual winter count from the Xerces Society recorded fewer than 2,000 butterflies, a massive drop from the tens of thousands in recent years and the millions that have clustered in trees from Marin County in northern California to the county. of San Diego in the south in the 1980s.
Western monarch butterflies head south to the Pacific Northwest to California every winter, returning to the same places and even the same trees, where they congregate to warm. Monarchs typically arrive in California in early November and spread across the country once the warmer weather arrives in March.
On the eastern side of the Rocky Mountains, another population of monarchs travel thousands of miles from southern Canada and the northeastern United States to spend the winter in central Mexico. Scientists estimate that the population of monarchs in the eastern United States has fallen by about 80% since the mid-1990s, but the decline in the western United States has been even more pronounced.
The Xerces Society, a nonprofit environmental organization that focuses on the conservation of invertebrates, recorded about 29,000 butterflies in its annual survey last winter. It wasn’t much different from the previous winter’s count, when there was an absolute minimum of 27,000 monarchs.
But this year’s tally is dismal. To the emblematic wintering of the monarch sites in the city of Pacific Grove, volunteers saw no butterflies this winter. Others sites well-known ones, such as Pismo State Beach Monarch Butterfly Grove and Natural Bridges State Park, have only hosted a few hundred butterflies, researchers say.
“These sites normally harbor thousands of butterflies, and their absence this year has been heartbreaking for volunteers and visitors who flock to these localities in the hopes of spotting the impressive flocks of monarch butterflies, ”said Sarina Jepsen, Species Director in endangered at the Xerces Society.
Scientists say butterflies are at extremely low levels in western states due to destruction of their milkweed habitat along their migratory route as dwellings spread across their territory and the use of pesticides and herbicides increases.
The researchers also noted the effect of climate change. Along with agriculture, climate change is one of the main drivers of the monarch’s threat of extinction, disrupting an annual migration of 4,828 kilometers synchronized with spring and the blooming of wildflowers. Massive wildfires across the western United States last year may have influenced their breeding and migration, researchers said.
A 2017 study by researchers at Washington State University predicted that if the monarch population fell below 30,000, the species would likely become extinct in the next few decades if nothing was done to save them. .
Monarch butterflies do not have legal protection from the state and the federal government to prevent their habitat from being destroyed or degraded. In December, federal authorities declared the monarch butterfly a “candidate” for threatened or endangered status, but said no action would be taken for several years due to the many other species awaiting designation.
The Xerces Company said it will continue to protect the monarch and work with a wide variety of partners “to implement science-based conservation actions urgently needed to help the iconic and beloved migration of the monarch of the West. “
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