Rod Webster, president of the Sierra Club in Merced, is involved in a local effort to help create more habitat for the western monarch butterfly population by seeking people who would be able to plant milkweed and other plants on rural land, or even in residential backyards, from a supply he will have available at his home in Merced.
Alarmingly, populations of western monarch butterflies, which formerly migrated to coastal overwintering sites in California in numbers exceeding one million, dwindled to less than 2,000 during the 2020-21 season.
Although the population had a rebound in 2021, Webster is still concerned.
“One possible reason for the rebound this year was the drought, which meant warmer weather,” he told the Times. “There was an effort to get the butterflies classified as a threatened or endangered species, but it was rejected because the migrating group that goes to Mexico is still fairly healthy so they said since only the California group was dwindling, they couldn’t designate the western monarch butterflies as a group that way.
“There are two main migrations — one goes down the center of our country and ends up in the central part of Mexico, and the other group migrates west over the Rockies and winters on the coast of California.
“That’s where we get our winter census of monarch populations and last year, 1,900 was all they counted, but this year, they counted 250,000. No one knows why they rebounded, but 250,000 is only 5 percent of the population we had in the 1980s so there is still concern that 250,000 was just a blip and might not mean the increase would continue.
“In 2020, the population was 1,900 and in 2019, it was 29,000, and it was 200,000 in 2017. It had some awfully low numbers. It has declined by 99.9 percent since the 1980s.
Since monarch butterflies need both plants for the adult butterflies to eat and milkweed for the adults to lay their eggs on during their migration, people are being encouraged to plant both milkweed and other types of plants.
Describing how the Sierra Club is involved, Webster told the Times, “Previously, in March 2020, we got seed donated from Bowles Farm and had the Merced College Horticulture class plant it for us. Most of the plants were supposed to be planted at the San Luis Wildlife Refuge, which is nine miles from Los Banos, but the weekend before the planting they closed the Visitor’s Center because of the pandemic, and we weren’t able to plant them.
“We had to scramble and find other resources, and as a result we found other organizations locally and in the foothills, especially Mariposa, and we have re-contacted them this year.
“This year, the seed was donated by the East Merced Resource Conservation District (EMRCD). EMRCD received seed from Xerces, and had quite a bit of leftover seed which they passed along to us. Two of their members were very active in the Sierra Club and they were happy to help out.
“The Fresno State University Horticulture class students took the seeds and grew the plants for us under the supervision of Jason Hurst, an instructor in the Department of Plant Science.
“My wife and I just picked up 1,000 plants in 2-inch pots which are about 4 inches tall, and 1,500 more plants will be available at the end of March, and they’re also preparing some seed for a third batch which will be ready in April.
“They are larger plants with more room for root growth than you would normally get for a mass planting. They are hardier and more likely to survive, and so don’t have to be planted immediately.
“People can plant milkweed in their back yards because of course the butterflies flying over land can identify where food is available and where they can lay their eggs. The butterflies are then long gone on their way, and the tiny caterpillars feed on the milkweed until they are mature enough to form a chrysalis and then they turn into monarch butterflies.
“For larger projects such as one-quarter acre or one-acre pieces of land, the landowner could plant 500 plants and it would only take up a couple of vegetable rows in their back garden.
“Most of the people who are committed right now are taking 3,200 plants which could be planted on a 6-foot by 5-foot plot of dirt.
“It doesn’t have to be a farm or a ranch; we need to do everything.
“For people to be supportive and become aware that we need to help the monarchs gives them personal buy-in to the cause, so even if someone gets a half dozen plants, it’s still a good little project.
“The plants need to be watered when they are young for two years, and then they will be self-sustaining unless we have a significant drought.
“You can’t use pesticides on the milkweed plants because the caterpillars will die when they eat the plants.
“Aphids love milkweed so one thought is to not plant milkweed next to garden plants you don’t want aphids on. Aphids can be knocked off the plants with water, however.”
Those interested in planting milkweed to help the monarch butterfly population can e mail Rod Webster with the Merced Group of the Sierra Club at [email protected] or phone him at 209-723-4747, and ideally he would like the potential planter to pick the milkweed up at his home in Merced. However, if transportation is a problem, Webster said he will try to work something out.
Other local efforts
Webster told the Times, “The San Joaquin Valley Monarch Conservation Working Group just formed this year. It got a grant to organize a coordinated effort to restore monarch habitat which is basically milkweed for the caterpillar stage, and other plants for the adults. The caterpillars will starve to death if they don’t eat milkweed.
“When the Monarch Conservation Working Group met recently, those at the meeting shared what they were trying to do, and we found out there were more than a dozen other projects to grow milkweed and also re-establish habitat for monarchs on their migration to California. Some of those which can operate on a larger scale are UC Cooperative Extension, the Great Valley Seed Company, and the resource conservation districts, which each county has.
“This group is finding areas that are neglected and getting some projects into those areas, and there are individual groups within that larger group getting grant funding for large projects.
“The Monarch Conservation Working Group is trying to come up with a project that everyone can be a part of and contribute to, to cement the group together, and the main project they’re promoting is establishing hedge rows which could grow between trees in an orchard and provide habitat for birds, insects and small mammals.”