By Barry Eberling
Jul. 19—Napa Valley wine country could potentially also be western monarch butterfly country — at least a little bit — at a time when the iconic orange-and-black butterfly needs help.
The butterfly faces challenges. An annual Thanksgiving count done in California found about 2,000 monarchs in 2020 before rebounding to 247,000 in 2021. Both numbers are far short of the more than 1.2 million recorded in 1997.
Researchers blame herbicides, habitat loss and climate change for the decline. Napans who think they are seeing fewer monarchs these days aren’t imagining things.
“That’s the crazy thing to me — basically in my lifetime, the population has almost disappeared,” said local resident Erin Arnsteen, a co-founder of the Western Monarch Society of Napa County.
In Napa County, the Western Monarch Society, Napa County Resource Conservation District, Xerces Society for Invertebrate Conservation and Monarch Joint Venture are trying to make a difference.
Western monarch butterflies in California are usually associated with such places as Pacific Grove. That city on the Monterey coast calls itself “Butterfly Town, USA” and hosts monarch grove sanctuary.
The butterflies spend the winter in Pacific Grove and other Central Coast locations. Then they migrate inland, with some passing through Napa County on their way out and back and some breeding here.
“We can have butterfly action in Napa County anytime between April and October,” Arnsteen said.
Monarch butterflies can lay eggs here on the sole plant that their caterpillars eat, the native milkweed. They also fuel up on nectar from native plant flowers for their migration journey.
Over the past year, the Resource Conservation District supported the planting of 2.5 acres of monarch butterfly habitat on 17 local farms. A recent survey found 48 eggs and at least three adult monarch butterflies at two habitat projects near vineyards.
“A really big success,” said Ruby Stahel of the Resource Conservation District. “It was so quick. We just planted these plants in November. Really, I didn’t think it would have an effect so quickly.”
She got a positive sign before she even reached the survey destination.
“We were driving up to the site and two monarchs were flying next to the pickup truck,” Stahel said.
She saw an even better sign for the monarch butterfly at a survey site.
“We actually watched one of them lay an egg in front of us,” Stahel said. “It was so amazing to see it all come together in such a short time.”
Meanwhile, the Western Monarch Society has been busy. In 2021 and 2022, it has given away 9,000 native milkweed plants and 2,000 native nectar plants.
One key is planting various milkweed species so that the butterfly can breed. The plants grow 2 to 4 feet tall and bloom in spring to fall, with flowers ranging from pink to white to purple.
Another key is planting nectar plants such as yarrow and aster so the butterflies can feed. Butterflies drink nectar from flowers with a tube-like mouthpart.
Plants need to be kept away from pesticides and pesticide drifts. “You don’t want to be calling in the monarchs and then poisoning them,” Stahel said.
Residents don’t need to own a farm or ranch to help the monarch butterfly. They can plant a couple of native milkweed plants or some flowering native plants. Visit https://westernmonarchs.org and look under resources to find a plant list.
“Even your backyard garden, that’s a little bit of space,” Arnsteen said. “Every little bit helps.”
Those residents won’t just be helping monarch butterflies with the nectar plants, but other native pollinator insects as well.
In that sense, the western monarch butterfly is the flashy star to grab people’s attention for a wider effort. Arnsteen called the butterfly “kind of the poster child” for what’s happening to native insects.
“Because it is so prolific and it is so iconic, people pay more attention to it,” Arnsteen said.
A total of $34,423 in grant money has supported the monarch push. Money comes from the county Wildlife Conservation Commission, California Association of Resource Conservation Districts, CARCD/ USDA Forest Service-International Program and the National Association of Conservation Districts. Xerces and Western Monarch Society provided additional plants.
You can reach Barry Eberling at 707-256-2253 or [email protected]
(c)2022 Napa Valley Register, Calif.
Visit Napa Valley Register, Calif. at www.napavalleyregister.com
Distributed by Tribune Content Agency, LLC.