PACIFIC GROVE, California – There’s a glimmer of hope for the vanishing orange-and-black western monarch butterflies.
The number that overwinters along California’s central coast is declining after the population, whose presence is often a good indicator of ecosystem health, reached a historic low last year. Experts determine their decline on climate change, habitat destruction and food shortages due to drought.
This year’s official count started on Saturday and will last three weeks, but already an unofficial count from scientists and volunteers shows that there are over 50,000 monarchs in overwintering sites, said Sarina Jepsen, director of endangered species at the Xerces Society for Invertebrate Conservation.
“This is certainly not a recovery, but we are really optimistic and just really happy that there are monarchs here, and it gives us some time to work towards restoring Western monarch migration,” Jepsen said.
Western monarch butterflies migrate south from the Pacific Northwest to California each winter, returning to the same places and even the same trees where they congregate to keep warm. The monarchs generally arrive in California in early November and spread across the country when the warmer weather arrives in March.
Monarchs from across the West migrate annually to about 100 wintering sites spread across Central California’s Pacific coast. One of the most famous wintering sites is the Monarch Grove Sanctuary, a city-owned site in the coastal city of Pacific Grove, where no monarch butterflies appeared last year.
The city 70 miles (112 kilometers) south of San Francisco has been working for years to help the declining population of the monarch. The city, known as “Butterfly Town, USA”, celebrates the orange and black butterfly with a parade every October. Messing with a monarch is a crime that carries a $ 1,000 fine.
“I do not remember having had so bad a year before and I thought they were done. They were gone. They will never come back, and certainly, this year, boom, they landed,” said Moe Ammar, president of Pacific Grove Chamber of Commerce.
This year, a preliminary count showed that more than 13,000 monarchs have arrived at the site in Monterey County, clustered on forty, cypress and eucalyptus trees and raised hopes among the grove’s volunteers and visitors that the fighting insects can return.
Researchers do not know why the population increased this year, but Jepsen said it is likely a combination of factors, including better conditions at their breeding grounds.
‘Climatic factors could have affected the population. “We could have had an influx of monarchs from the eastern United States, which can happen occasionally, but it is not known for sure why the population is what it is this year,” she said.
Eastern monarch butterflies travel from southern Canada and the northeastern United States across thousands of miles to spend the winter in central Mexico. Researchers estimate that the monarch population in the eastern United States has declined by about 80% since the mid-1990s, but the decline in the western United States has been even steeper.
Western monarch butterfly populations have fallen by more than 99% from the millions that overwintered in California in the 1980s due to the destruction of their dairy plant habitat along their migratory route as homes expand into their territory and the use of pesticides and herbicides are rising.
Researchers have also noted the effects of climate change. Along with agriculture, climate change is one of the main drivers behind the monarch’s threatened extinction, disrupting an annual 3,000-mile (4,828-kilometer) migration synchronized with spring and the flowering of wildflowers.
“California has been in a drought for several years now, and they need sources of nectar to fill their stomachs and be active and survive,” said Stephanie Turcotte Edenholm, an associate professor at the Pacific Grove Natural History Museum, which offers guided tours of the sanctuary. “If we do not have nectar sources and we do not have the water that provides it, then that is a problem.”
Monarch butterflies lack state and federal legal protection to prevent their habitat from being destroyed or degraded. Last year, they were denied federal protection, but the insects are now among the candidates for inclusion under the federal Endangered Species Act.
Rodriguez reported from San Francisco.