What are the odds?
Here you are, standing in the garden section of a home improvement store, and you select a tropical milkweed to purchase. You place it on the ground and admire the brilliant yellow blossoms and luxurious green foliage. It's the best of the best. Just as you're about to pick it up and place it in a cart, a monarch lands on it and begins laying eggs.
What are the odds?
That happened to us around Wednesday noon, Sept. 4 in Vacaville as we were purchasing an end-of-the-season Asclepias curassavica.
Most likely, the plant had been in the nursery since last spring, as it was root-bound. We took it home, replanted it in a larger pot, and set it in the sun. Milkweeds like full sun. And monarchs go where their host plant is, whether it be in the wild, in your backyard, in your city park, or in a garden section of your local home improvement store.
Hopefully, the monarch eggs will hatch and this tropical milkweed will yield some caterpillars, chrysalids and adults.
Ironically, we found a monarch laying eggs in the garden section of a home improvement store!
Said entomologist David James of Washington State University, Pullman, who researches migratory monarchs: "That's an amazing story...selecting your milkweed and then having a female come over and deposit a few eggs for you!"
As an aside, as we were purchasing the milkweed, I casually asked the clerk at the check-out line "Have you seen any monarchs here?"
"Not in HERE," she said, surprised I would ask such a question. She tallied up the sale as "Mama Monarch" fluttered around her nursery, unnoticed, laying the next generation.
Curiously enough, a family member recorded a monarch laying eggs in the garden section of that same store the day before. About the same time. Maybe the same monarch. (See YouTube video)
Butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, who has monitored all butterfly populations in the central valley for more than four decades and publishes his research on a website, says that “this is the biggest milkweed year in northern and central California in living memory. Speciosa is up to 5' tall and some fascicularis almost as big, and both are covered with both genera of Lygaeids (milkweed bugs), plus both oleander and gray aphids. But Monarchs only showed up here about two weeks ago! Lots of milkweed, no Monarchs to use it. I have seen 10 Monarchs in 2019 and have not seen a wild larva since 2017, and I am afield 260 days a year.”
Sometimes life just isn't fair. Entomologist Lynn Kimsey, director of the Bohart Museum of Entomology and professor of entomology at UC Davis, commented “Weirder and weirder. They still haven't found MY milkweed.”
You could call it a slacker, a deadbeat, a moocher, a sponger, or a loafer.
Or you could call it a cuckoo bee.
Take the cuckoo bee, Xeromelecta californica, a parasite of the digger bee, Anthophora.
When the female Anthophora leaves its nest to collect more pollen, the female cuckoo bee sneaks in and lays an egg.
"When the host female seals her nest, it seals the doom of her own offspring," distinguished emeritus professor Robbin Thorp of the UC Davis Department of Entomology and Nematology told the crowd at last week's 40th annual Western Apicultural Society meeting, held at UC Davis. They eat the provisions, a pollen ball meant for the host offspring, and kill and eat the host larvae.
The cuckoo bee offspring emerge.
Thorp, co-author of California Bees and Blooms: A Guide for Gardeners and Naturalists, also called attention to their "pointy abdomen" and "wasp-looking appearance."
But they are bees--cuckoo bees. They're also called parasitic bees or "kleptoparasites" or "cleptoparasitises."
They have no pollen-carrying/collecting apparatus, like a scopa, because they don't need any, Thorp said, just as they do not construct their own nests.
If you look around a pollinator garden, you just might sight some cuckoo bees. Last week we saw a Xeromelecta californica (as identified by Thorp and Lynn Kimsey, director of the Bohart Museum of Entomology and UC Davis professor of entomology). It was sipping nectar from a tropical milkweed, Asclepias curassavica.
We've also spotted Anthophora urbana nectaring on our lavender.
One thing's for certain: a cuckoo bee didn't lay its eggs in the Anthophora nest that time or the urbana wouldn't have been there.
A fly, oh, my!
On the approval scale, they don't rank nearly as high as honey bees, but some are often mistaken for them.
Take the Eristalis stipator, which belongs to the family Syrphidae, the hover flies.
It's about the same size as a honey bee and it's a pollinator.
We recently spotted this one--a female Eristalis stipator, as identified by senior insect biosystematist Martin Hauser of the California Department of Food and Agriculture--nectaring on tropical milkweed, Asclepias curassavica. The colors are striking--both the colors of the fly and the flowers. It's a striped fly, with black and white bands, one superimposed gold band, and buff-colored hairs piled on the thorax. And the showy flower, aka "blood flower," is red-orange with a yellow hood.
Eristalis is a large genus of approximately 99 species. The Eristalis stipator has no common name, so we just call it Eristalis stipator.
Or a fly.
A little haggard, a little worn, a little ragged, a little torn.
But there she was on Monday, Aug. 1, the first monarch of the season to lay eggs in our little pollinator garden in Vacaville, Calif.
She found the milkweed, but that was AFTER the aphids, milkweed bugs, praying mantids, assassin bugs and assorted spiders claimed it.
It's always a joy to see the majestic monarch fluttering through a pollinator garden. On Sunday, July 31, a male lingered for two hours, nectaring on the Mexican sunflower (Tithonia) as the male territorial longhorn bees tried to chase him away. No welcome mat for him! No place setting for him!
Then today, a female arrived, first stopping by the showy milkweed, Asclepias speciosa, to lay eggs and then fluttering over to the tropical milkweed, Asclepias curassavica, to lay more.
It's amazing how the monarchs, Danaus plexippus, know how to put their "resources" in multiple places. Like the idiom that cautions "don't put all your eggs in one basket," instinctively they seem to know that if they put all their resources in one place, they could lose them all. There's a better chance of offspring survival if they spread the eggs around.
All summer and into fall, we spotted the familiar reddish, black and white bugs scurrying around on our showy milkweed, Asclepias speciosa, and tropical milkweed, Asclepias curassavica.
Showy bugs on showy milkweed.
The ones we saw: the Small Milkweed Bug, Lygaeus kalmii. Like its name implies, it's small, about half an inch long.
They're primarily seed eaters, but they're opportunistic and generalists, says insect migration biologist Hugh Dingle, emeritus professor of the UC Davis Department of Entomology and Nematology, author of the popular textbook, Animal Migration: the Biology of Life on the Move. "They'll get protein from wherever they can find it," he said. Dingle, whose research includes migratory monarchs, said the milkweed bugs not only eat seeds, but they also eat monarch eggs and larvae and the immature stages of other butterflies. Forever the opportunists, they eat other small bugs as well--if the opportunity arises. And they feed on nectar, too.
Some scientists have seen them feeding on insects trapped in the sticky pollen of the showy milkweed.
The bugs, it seem, have few predators. They feed on the toxic milkweed, which makes them distasteful to predators, prey to avoid. Their warning colors (red and black) strike home that fact.
In the fall, as the seed pods burst open, it's a horticulture/culinary war between the milkweed growers and the milkweed bugs. Both want the seeds: the humans to plant them and the bugs to eat them.
(Note: Research shows that the milkweed bug also feeds on other plants. Read about the opportunist Small Milkweed Bug in the Journal of the New York Entomological Society.)