Posted on Wednesday, November 17, 2021 | 4:05 p.m.
Updated 5 hours ago
PACIFIC GROVE, Calif. (AP) – There is a silver lining for the disappearing orange and black western monarch butterflies.
The number of winterers along California’s central coast is rebounding after the population, whose presence is often a good indicator of ecosystem health, hit an all-time high last year. Experts attribute their decline to climate change, habitat destruction and lack of food due to drought.
An annual winter tally last year by 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 congregated in trees in Mendocino County. in Northern California to Baja California, Mexico, in the south in the 1980s. Now their roosting sites are mainly concentrated on the central coast of California.
This year’s official tally started on Saturday and will run for three weeks, but already an unofficial tally by researchers and volunteers shows there are more than 50,000 monarchs at the wintering sites, said Sarina Jepsen, Director of Endangered Species at the Xerces Society for Invertebrate Conservation.
“It is certainly not a recovery, but we are really optimistic and really happy that there are monarchs here and it gives us some time to work on the resumption of Western monarch migration,” Jepsen said. .
Western monarch butterflies move southward from the Pacific Northwest to California every winter, returning to the same places and even the same trees, where they congregate. Monarchs typically arrive in California in early November and spread across the country once the warmer weather arrives in March.
The western monarch population has declined by over 99% since the 1980s.
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 winter in western Mexico. Scientists estimate that the population of monarchs in the eastern United States has fallen by about 80% since the mid-1990s.
It is not yet known whether the population of monarchs traveling to Mexico from the east of the country has rebounded. Results of an annual county by World Wildlife Fund experts in Mexico won’t be released until next year.
Monarchs from across the West migrate to approximately 100 wintering sites that dot the Pacific coast of central California each year. One of the most well-known wintering grounds is the Monarch Grove Sanctuary, a site owned by the city of the coastal town of Pacific Grove, where no monarch butterfly showed up last year.
The city 70 miles south of San Francisco has worked for years to help the monarch’s declining population. Known as “Butterfly Town, USA”, the city celebrates the orange and black butterfly with windowpane patterns in its wings with a parade each October. Playing with a monarch is a felony punishable by a fine of $ 1,000.
“I don’t remember having had such a bad year before and thought it was over. They were gone. They’re never coming back and of course this year, boom, they’ve landed, ”said Moe Ammar, president of the Pacific Grove Chamber of Commerce.
This year, a preliminary tally showed more than 13,000 monarchs have arrived at the Monterey County site, clustering on pines, cypresses and eucalyptus trees and sparking hope among volunteers and visitors to the grove that the struggling insects can bounce back.
Scientists don’t know why the population has increased this year, but Jepsen said it was likely a combination of factors, including better conditions on their breeding grounds.
“Climatic factors may have influenced the population. We could have received an influx of monarchs from the eastern United States, which can sometimes happen, but it’s unclear why the population is what it is this year, ”Jepsen said.
Scientists say the monarch population has fallen sharply due to the destruction of their milkweed habitat along their migratory route, as homes spread across their territory and the use of pesticides and herbicides increases.
Along with agriculture, climate change is a major driver of the monarch’s threat of extinction, disrupting an annual migration of 3,000 miles (4,828 kilometers) synchronized with the spring and flowering of wildflowers.
“California has been in a drought for several years now and it needs nectar sources in order to fill its tummy, be active and survive,” said Stephanie Turcotte Edenholm, a teacher at the Pacific Grove Natural History Museum who offers Guided tours of the sanctuary. “If we don’t have sources of nectar and we don’t have the water to provide it, then that’s a problem. ”
Monarch butterflies do not have national and federal legal protection to prevent their habitat from being destroyed or degraded. Last year, they were denied federal protection, but the bugs are now among the candidates for listing under the federal Endangered Species Act.
Rodriguez reported from San Francisco.