- Author: Kathy Keatley Garvey
It's beginning to look a lot like...Halloween.
If you haven't noticed, stores are gearing up for Halloween with assorted ghosts, goblins and ghouls for you.
We remember Halloween 2023 when a female migratory monarch fluttered into our pollinator garden. She checked out the milkweed (we had several native and one non-native species) and chose to sip nectar on the tropical milkweed, Asclepias curassavica, a non-native.
We managed to capture several images of her around 5:30 p.m. before she left on her journey to overwinter in coastal California.
The Center for Biological Diversity, headquartered in Tucson, says on its website: "Across their range, monarchs are threatened by pesticides, climate change, ongoing suburban sprawl, and fragmented and poisoned habitats as they navigate their way across the continent. They need a helping hand from the government, businesses and concerned individuals."
Threats? To that we'd add a minor threat: such predators as birds, spiders and mantises.
Monarchs in western North America overwinter in coastal California (roosting in eucalyptus, Monterey pines, and Monterey cypresses), while those in eastern North America "have a second home in the Sierra Madre Mountains of Mexico" (roosting in oyamel fir forests), as noted by the U.S. Forest Service.
"Researchers are still investigating what directional aids monarchs use to find their overwintering location," the U.S. Forest Service says. "It appears to be a combination of directional aids such as the magnetic pull of the earth and the position of the sun among others, not one in particular."
We're glad to see that the raging controversy over native vs. non-native milkweed is subsiding a bit, as the more crucial threats are pesticides, habitat loss, and climate change. After all, tropical milkweed, a native of Mexico, has been in California for more than 100 years. And longer than that when you consider that California was once part of Mexico. A. curassavica is also native to Central America (including Belize, Costa Rica, El Salvador, Guatemala, Honduras, Nicaragua, and Panama) and South America (including Colombia, Ecuador, Peru, and Venezuela), according to Johnny Butterflyseed.
- Author: Kathy Keatley Garvey
It lived--and quite hidden at that--through the freezing cold, the rain, and the wind. It surfaced today on a milkweed in our Vacaville pollinator garden.
Surprise, surprise! We neither saw it as an egg nor as a tiny caterpillar.
"Most larval mortality in monarchs occurs in the first 2 or 3 instars.. so they keep as hidden and low-key as possible," entomologist David James, an associate professor at Washington State University, told us. "Once they make it to the fourth instar, they are emboldened and are more likely to be seen exposed."
James, who studies migratory monarchs, earlier commented on the fall breeding: "The egg laying females you are seeing now are likely migrants that have eschewed reproductive dormancy for reproduction. This has probably always happened to some extent but is likely more significant now because of warmer falls. The lack of activity in summer in Vacaville was probably a function of most of the population having dispersed further east and north, maybe more than usual? They surely did pass through Vacaville in spring on their way north but clearly didnt stop to use your milkweeds. It does seem that some years they are more prone to frequent stopping/oviposition on their way north and east, yet in others they just keep flying. There's evidence that the latter was the case this year... with as many migrants making it to BC as to Washington...Normally they stop in Washington and only a handful make it to BC."
James is the author of a newly published book, The Lives of Butterflies: A Natural History of Our Planet's Butterfly Life (Princeton University) with colleague David Lohman of the City College of New York. The book, released in the UK on Oct. 3, 2023, will be available in the United States starting Jan. 9, 2024.
Irish scientist Éanna Ní Lamhna recently interviewed the WSU entomologist in a podcast on RTÉ, or Raidió Teilifís Éireann. The book, Lamhna said, "showcases extraordinary diversity of world's butterflies, while exploring their life histories, behavior, conservation and other aspects of these most fascinating and beguiling insects." (See Bug Squad blog). Listen to the butterfly podcast here:
https://www.rte.ie/radio/radio1/clips/22294525/
Meanwhile, we checked another milkweed plant in the garden today and spotted another caterpillar, this one a little smaller and less active than the first.
As UC Davis distinguished professor Lynn Kimsey, director of the Bohart Museum of Entomology, commented: "So much for diapause!"
Now our milkweed garden includes scores of hungry aphids, several species of milkweed, two 'cats, and maybe three (one 'cat went missing and is probably j'ing somewhere) and four chrysalids.
Will we have a Merry Chrysalis?
- Author: Kathy Keatley Garvey
Question: What's better than seeing a monarch butterfly?
Answer: Seeing two monarch butterflies sharing the same blossom on a butterfly bush!
Scenario: Monarchs (Danaus plexippus) from the Pacific Northwest are fluttering through Vacaville, Calif. and stopping in our pollinator garden for some flight fuel before heading off to their overwintering sites along coastal California.
Background: I am watching for tagged butterflies from the migratory monarch project of Washington State University entomologist David James. (After all, one tagged by his citizen scientist Steven Johnson of Ashland, Ore., on Aug. 28, 2016, fluttered into our yard seven days later. James said it flew 285 miles in 7 days or about 40.7 miles per day.)
Menu: In our pollinator garden, the flight fuel includes nectar from the Mexican sunflower (Tithonia rotundifola), tropical milkweed (Asclepias curassavica), butterfly bush (Buddleia davidii), and Zinnias, a genus of plants of the tribe Heliantheae within the family Asteraceae.
Action: On Sept. 27, a male monarch touches down on our butterfly bush and begins sipping nectar. Soon, another joins him.
The two monarchs engage in what appears to be a territorial battle. It's a kaleidoscope of orange and black wings, tumbling, wobbling, recovering.
And then, wings up! The monarchs take flight.
- Author: Kathy Keatley Garvey
"More than beautiful, monarch butterflies contribute to the health of our planet. While feeding on nectar, they pollinate many types of wildflowers.--National Park Service.
Have you ever seen pollen on a monarch butterfly?
This morning a male migrating monarch, probably on its way to coastal California to an overwintering site, stopped at a Vacaville garden to sip some nectar on a Mexican sunflower (Tithonia rotundifola).
If you look closely, you can see the gold pollen.
Monarchs are not just iconic species facing a population decline, they're pollinators.
"Pollinator species, such as bees, other insects, birds and bats play a critical role in producing more than 100 crops grown in the United States," according to the U.S. Department of Agriculture. "Honey bee pollination alone adds more than $18 billion in value to agricultural crops annually."
- Author: Kathy Keatley Garvey
If you live in California, tagged monarchs from the migratory research project of entomologist David James of Washington State University may be heading your way.
One tagged monarch, a male, fluttered into our Vacaville pollinator garden on Sept. 5, 2016. Citizen scientist Steven Johnson of Ashland, Ore., tagged and released it on Aug. 28. It nectared on Mexican sunflowers (Tithonia rotundifola) and a butterfly bush (Buddleia davidii) before heading to an overwintering site in coastal California.
The tag read “Monarch@wsu.edu A6093.”
James later told us: "So, assuming it didn't travel much on the day you saw it, it flew 285 miles in 7 days or about 40.7 miles per day. Pretty amazing."
If you see a tagged monarch ("quite a few are being tagged in southern Oregon," James says), try to take an image. Then detail the information (where spotted and when) and send it to the WSU entomologist at monarch@wsu.edu. Read more on his Facebook page, Monarch Butterfies in the Pacific Northwest.
Meanwhile, we've been seeing monarchs daily in our garden since late August. We spotted one monarch laying eggs on our tropical milkweed, Asclepias curassavica, on Aug. 10. (That was her choice of milkweed: she ignored the narrow-leafed milkweed, A. fascicularis; the showy milkweed, A. speciosa; and the butterfly weed, A. tuberosa.)
On Sept. 5, two monarchs, a male and a female, eclosed, while a male monarch patrolled overhead. The newcomers dried their wings and fluttered off. Both managed to escape several predators: Western scrub jays, praying mantises, and assorted crab spiders.
Welcome to the world!
