Nearly a month ago, there was something miraculous in the air. Seemingly millions of butterflies were in migration, literally dancing before people’s faces. But in that migration, not that many monarchs were in flight. The dazzlingly beautiful monarchs are on the decline—and severely so.
Like so many other creatures on this planet, monarchs are a threatened species. As global warming increases, monarch habitat moves further northward, causing longer migrations for the butterflies. At some point, monarchs may be forced to produce another generation to reach further north, and only a few may be able to make the longer trip back to Mexico or California for the winter.
The monarch overwintering population in Pacific Grove in Pismo Beach has dwindled more than 80 percent. What used to look like a frenzy of flowers on the trees now appears to have nothing but a few blossoms—those “blossoms” are the monarchs fortunate enough to have survived.
But there are things that anyone can do to help the monarchs thrive. First, grow plenty of milkweed, which monarch butterflies use as their host plants to lay their eggs under the leaves of the plants. Especially at this time of the year, the best thing that new or beginning monarch “parents” can do is to plant milkweed. Seeds take a little longer to germinate, so plants in pots would jumpstart the project. Jessica Griffiths, a San Louis Obispo-based environmental consultant and field biologist who has studied monarch behavior, explained that milkweed is the only plant that monarch caterpillars use for food. Monarch adults live a few weeks and are productively active in California for three to four generations from the months of April to August.
“Milkweed is vital for monarchs,” she said. But for various reasons, including the destruction of natural habitat, milkweed has grown scarce.
Sue Slaughter, a local teacher at Grossmont Adult School at the Foothills Center has taught classes on how to raise monarchs.
“Monarchs can do well without a lot of human intervention,” she said. “If you raise them outside, nature takes over and you can do as little or as much as you like. Milkweed plants are low maintenance, and they’re easy to grow.”
One thing to watch out for is over-watering the milkweed. If the leaves turn yellow, decrease the water. If the leaves continue to droop in the afternoon, more water is needed.
Usually only 2-3 percent of the eggs make it to the butterfly stage, so Slaughter chooses to raise some inside, just to increase the number.
La Mesa Beautiful, an association that awards wise gardening and gives tips to growing and maintaining beautiful yards, often has informative sessions on how to attract pollinators like monarchs. The late Marcia Van Loy, who participated in the Master Gardener Program, gave a talk not long ago at a quarterly meeting of La Mesa Beautiful about how to make one’s yard or garden attractive to butterflies. She explained that a drought-tolerant garden is good not only because it does very well in strong sun, but also because pollinators thrive. Monarchs need the sun in order to help their bodies warm up enough to fly.
This need for butterflies to be warm enough to fly is particularly true as they newly emerge from their chrysalises. “They have to pump hemolymph–that’s butterfly blood–by pumping their wings in the sun,” explained Griffiths.
“The decrease in monarch population is also probably due to our winters getting warmer. So they leave the overwintering sites sooner,” she said.
As the planet gets warmer and experiences major weather changes, greater monarch mortality happens because of the wind, cold and severe storms. Neither does smoke from wildfires help the plight of the monarchs.
Use of pesticides and chemicals that deplete the ozone in the atmosphere causes air pollution which add to the problem of global warming. But individuals can help in that matter, too.
“Most important that I hope you walk away with today,” Van Loy had said after her lecture at La Mesa Beautiful, “is that you should not use pesticides of any kind in your garden or yard. Just let nature take its course.”
That—and buy milkweed at nearly any nursery in San Diego.
Classes, workshops and other events on attracting butterflies and other pollinators as well as other gardening topics are available at the Master Gardener Program. Go to www.mastergardenersd.org for more information. La Mesa Beautiful is another good source at www.lamesabeautiful.org.