- Author: Denise Godbout-Avant
As the long, hot days of summer slide into cooler, shorter days of autumn, seasonal changes are occurring in my garden. Not as many plants are blooming, the leaves on deciduous trees and plants are becoming drier and starting to change color. Some plants are producing autumn berries that will sustain many birds as insects, another source of food, begin to disappear.
Quite a few butterflies have been showing up in my garden to take advantage of flowers that are still blooming. Butterflies I have been seeing include painted ladies (Vanessa cardui), common buckeyes (Junonia coenia), fiery skippers (Hylephila phyleus)and cabbage whites (Pieris rapae).
With the advent of winter, butterflies disappear since they cannot tolerate temperatures below 55°F or rainy weather. So, what happens to butterflies in the winter???
Some Butterflies Migrate
Some butterfly adults migrate south, overwintering in warmer climates.
Monarch butterflies are known for their astonishingly long spring and fall migrations. Both the eastern monarchs and western monarchs began their southern migrations in late August or early September from southern Canada/northern USA to their overwintering sites. The eastern variety generally heads to the oyamel fir forests in the mountains of central Mexico, whereas the western Pacific species have a shorter journey to California's coastline. You may see some western monarchs this fall resting or feeding on flowers in your garden as they fly through the Central Valley on their way their overwintering sites in coastal areas such as Santa Cruz, Pacific Grove, Pismo Beach, and San Diego.
Other Winter Strategies
Most butterflies spend winter in the same area they spent summer.
Some lay their eggs in autumn on, or close to, their specific host plants with the eggs hatching the following spring. The common hairstreak (Satyrium californica) eggs are laid attached to twigs of oaks with the caterpillars feeding on newly emerged spring leaves.
Some butterflies weather the cold as pupa within a chrysalis in a sheltered spot. During this time, the pupa will enter diapause (where development stops). An antifreeze chemical in their blood allows them to survive cold temperatures. Once the days lengthen, it will resume its transformation, emerging as an adult just as in time for blooming flowers that provide nectar. The tiger swallowtail's chrysalis (Papilio rutulus) will take refuge in deep shrubbery. The anise swallowtails (Papilio zelicaon) and cabbage whites also generally overwinter as a pupa in their chrysalis. Fiery skippers usually overwinter as pupae buried in leaves, but some adults will migrate to southern California.
Mourning cloaks (Nymphalis antiopa)go into dormancy as an adult. Their blood also contains an anti-freeze. They tuck themselves into cracks and crevices of rocks and trees.
Leaving the Leaves
- Learn which butterflies live in your area and grow native plants for those specific species.
- Offer nectar plants in the fall and spring months for butterflies that are migrating, emerging from overwintering, or getting ready to go into winter dormancy/hibernation.
- Skip raking the leaves in your garden in autumn and leave standing plants alone until midspring, so overwintering butterfly larvae, pupae and adults have a place to hide. If leaving the leaves on your lawn is too messy for you, consider not disturbing the leaves in your planters.
- If you find what looks like a dead chrysalis (many resemble dead leaves) in your yard, garage, shed, do not disturb it. A butterfly may well emerge in the spring.
- Avoid using pesticides as much as possible.
Resources
- Art Shapiro's Butterfly Site: https://butterfly.ucdavis.edu/butterflies
- Butterflies in Your Garden, Publication from UCCE Stanislaus County :https://ucanr.edu/sites/CEStanislausCo/files/345791.pdf
- Xerces Society - Pollinator Plants: Central Valley of California: https://xerces.org/publications/plant-lists/ppbi-california-central-valley
- California Native Plant Society: https://www.cnps.org/
- UC Davis Arboretum – Larval Hosts for Butterflies: https://arboretum.ucdavis.edu/blog/larval-host-plants-butterflies
Denise Godbout-Avant has been a UC Cooperative Extension Master Gardener in Stanislaus County since 2020.
/h3>/h3>/h3>/h3>Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
MGCC Help Desk Response: Thank you for contacting the UC Master Gardener Program Help Desk with a question about overwintering Gerbera Daisies. Gerberas are perennial plants but are often treated as annuals. They need regular deep water and do best in rich, well-drained soil. They should be fertilized monthly during the bloom period. They do well in full sun, but in hot areas such as most of East County, they need partial shade. If you have a nice clump of them, you must be doing something right!
They should overwinter in the ground just fine in East County. According to Sunset Western Garden Book, they can be grown as perennials in zones that get even colder than your Zone 9. As long as the soil drains well and doesn't become waterlogged when it rains, your gerberas should be OK.
Mulch is almost always a good idea. It protects the soil and helps maintain even moisture levels. Just make sure you keep the mulch a couple of inches away from the plants' stems to avoid rotting.
Please let us know if you have more questions.
Help Desk of the UC Master Gardener Program of Contra Costa County (SEH)
Notes: Contra Costa MG's Help Desk is available almost year-round to answer your gardening questions. Except for a few holidays (e.g., last 2 weeks December), we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 2380 Bisso Lane, Concord, CA 94520. We can also be reached via telephone: (925) 608-6683, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/. MGCC Blogs can be found at http://ccmg.ignore.edu/HortCoCo/ You can also subscribe to the Biog.
- Author: Kathy Keatley Garvey
Science journalist Janet Marinelli, writing in Yalee360, said it well in her Dec. 21st piece, "To Protect Monarch: a Plan to Save the Sacred Firs."
This should be widely read, widely distributed and widely discussed.
Basically, it's crucial to plant milkweed, the host plant of the besieged and dwindling monarch, but it's also crucial to plant more oyamel fir trees (Abies religiosa) in central Mexico, where deforestration and climate disruption and loss of milkweed combine to rage an ongoing war against the migrating monarchs. These firs are the favorite of overwintering monarchs that migrate from the Eastern United States, and as far away as Canada.
This tree is called a sacred fir ”because of its narrow, conic tip that resembles clasped hands with fingers pointed upwards, praying," Marinelli writes. "These dense, dark-green conifers protect the monarchs from cold and rainy winter nights."
Says Wikipedia: "Sacred fir is named after the use of cut foliage in religious festivals in Mexico, notably at Christmas. It is also the preferred tree for the monarch butterfly (Danaus plexippus) to reside in colonies during its hibernation in Mexico. The distribution of this tree is narrowing because of deforestation and human impact."
The fir is on the International Union for the Conservation of Nature (IUCN) Red List of Threatened Species.
"A billion butterflies once fluttered down from as far as southern Canada to paint the firs a quivering crazy quilt of orange and black with white spots," Marinelli eloquently wrote. "But due to the usual litany of destructive factors — from the deforestation of Mexico's oyamel fir trees to the loss of milkweeds, the primary host plants for monarch caterpillars up north — their numbers have plummeted. By 2014, there were just 33 million of them "
So the scientists in Mexico seek to plant these trees at higher altitudes--not just to save this species of trees, but to save the monarchs.
Cuauhtémoc Sáenz-Romero, a forest geneticist at the Universidad Michoacana de San Nicolás de Hidalgo, and the plan's architect, was saying: “We have to act now. Later will be too late, because the trees will be dead or too weak to produce seeds in enough quantity for large reforestation programs.”
Agreed. It's important to act now. "Later will be too late." Saving the sacred firs is a crucial tool in the save-the-monarch toolbox.
Humankind, so apt at destroying habitat instead of protecting it, now needs to backtrack and save the environment, the firs and the monarchs.
Before. It. Is. Too. Late.
- Author: Kathy Keatley Garvey
Is the overwintering monarch butterfly population along California's coast increasing or decreasing?
"So far, far the picture is rather mixed for the number of monarchs in California," according to Matthew Shepherd, communications director for the Xerces Society for Invertebrate Conservation. "More than 130 sites have been surveyed," he told us today. "Northern sites have more butterflies that last year, other sites fewer, and there are many southern sites that haven't yet reported data. A full analysis will be available in January."
The western monarchs, that is those that west of the Rockies, migrate to the California coast to overwinter while the eastern monarchs head to the mountains of central Mexico.
In a news release issued today from its headquarters in Portland, Ore., the Xerces Society said that early data from its Western Monarch Thanksgiving Count suggests "a small increase in butterfly numbers in some parts of the overwintering range."
That is, 2015 may have "been a better year for the beleaguered monarch butterfly in the western United States."
"The overall population size is still far lower than it was in the 1990s, when more than one million butterflies were counted," the news release said. "The surveys indicate that sites north of Santa Cruz are hosting more butterflies than previous years, whereas sites in Monterey, San Luis Obispo, and Santa Barbara counties are reporting fewer numbers of butterflies on average. Several new sites have been reported, including some from Marin County with up to 10,000 monarchs. The data is not yet available for Santa Cruz County and southern California."
The Xerces Society launched its Western Monarch Thanksgiving Count in 1997. This year some 85 volunteers surveyed more than 130 sites over a three-week period centered around Thanksgiving.
We'll all have to wait until January to see the final tallies.
Meanwhile, we were happy to see monarchs roosting in November in the Berkeley Aquatic Park (for the first year ever) and on Mare Island, Vallejo, (maybe also first?) but those clusters may be temporary. As butterfly guru Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, says--they may move on as soon as the weather turns foul.
Maybe they're on their way to Santa Cruz?
"There are some sites where monarchs gather in fall, almost like staging posts in preparation for moving to overwintering locations," Shepherd told us.
Be sure to read the Xerces Society blog by Sarina Jepson, endangered species program director of the Xerces Society, and the news release issued by Xerces Society.
Where can you observe the overwintering monarchs in California? The Xerces Society has kindly provided a web page with links to overerwintering sites in Alameda, Santa Cruz, Monterey, San Luis Obispo and Santa Barbara counties.
- Author: Kathy Keatley Garvey
A mid-life chrysalis?
Well, maybe not mid-life, but definitely out of season.
A female monarch butterfly eclosed today in our little indoor butterfly habitat. Two weeks ago, we “rescued” the caterpillar from a narrow-leafed milkweed plant in our Vacaville pollinator garden and brought it inside. Our goal: conservation. We sought to protect it from prey, including the resident scrub jays.
So, this morning, we lost a chrysalis and gained a butterfly. She was right on schedule: Eclosure after 10 days as a chrysalis.
When the temperature hit 61 degrees at around 1 p.m., we released her. She fluttered a bit, and then soared straight up, a good 80 feet high. Usually when we release the monarchs, they flutter around, sometimes touching down on a bush and sometimes soaring over it. This one wasted no time.
On its way to Santa Cruz?
Not sure. At 3:30 p.m., we spotted a monarch butterfly--same one?--roosting on our African blue basil as a dozen honey bees buzzed around, gathering nectar.
Meanwhile, the fellow members of her species are winging their way to their overwintering sites: the monarchs east of the Rockies to the Sierra Madre Mountains in Mexico, and those west of the Rockies to the California coast, including the Natural Bridges State Beach in Santa Cruz, and Pacific Grove in Monterey County. They cluster in eucalyptus, Monterey pines, and Monterey cypresses.
Monarchs do not fly at night. They travel only during the day and then find a roosting spot for the night. "Roost sites are important to the monarch migration," according to the U.S. Department of Agriculture's Forest Service. "Many of these locations are used year after year. Often pine, fir and cedar trees are chosen for roosting. These trees have thick canopies that moderate the temperature and humidity at the roost site. In the mornings, monarchs bask in the sunlight to warm themselves."
How many miles can monarchs travel a day? Between 50 to 100 miles, the Forest Service says. "It can take up to two months to complete their journey. The farthest ranging monarch butterfly recorded traveled 265 miles in one day."
Monarchs use a combination of directional aids, including the magnetic pull of the earth and the position of the sun. They take advantage of the air currents and thermals as they head toward their overwintering sights.
To think that we humans can barely make it out of the neighborhood without our GPS devices!
As of 5 p.m., the monarch roosting on the African blue basil is still there. The bees are gone, back to the warmth of their hives.
Tomorrow, our little buddy will warm her flight muscles, sip a little nectar, and take flight.
Safe travels, Miss Monarch!