A pollinator garden is a study in diversity--and of inclusion and exclusion.
The residents, the immigrants, the fly-bys, the crawlers, the wigglers, the jumpers. The big, bad and bugly. The prey and the predators. The vegetarians and carnivores.
The nectar-rich flowers attract honey bees, bumble bees and butterflies. And right near them are the predators: the praying mantids, dragonflies and assassin bugs.
The assassin bugs, family Reduviidae, are ambush predators. They resemble human assassins (or at least those on the movie screen!): long narrow neck, beady eyes, and sturdy body. When they ambush a predator, they stab it with their rostrum, inject venom, and suck out the juices. Or as UC Berkeley entomologists Jerry Powell and Charles Hogue write in their book, California Insects, "The victims, which include all kinds of insects, are snatched by quick movements of the forelegs, and immediately subdued by a powerful venom injected through the beak."
Such was the case with the assassin bug, Zelus renardii, this week. We watched one lie in wait on a Mexican sunflower (Tithonia); we watched another dine on an unidentifiable prey on a milkweed blossom; and we watched yet another stab a lady beetle (aka lady bug) on a leaf.
Everybody eats in the pollinator garden.
We never thought we'd see one this year.
And then it arrived.
The first monarch sighting of the year.
A Danaus plexippus majestically touched down on our Mexican sunflowers (Tithonia) around 5 this afternoon in our pollinator garden in Vacaville, circled the milkweed plants about 10 times, and then fluttered over the roof and vanished.
Meanwhile, we managed to grab a couple of photos of the iconic butterfly.
Fellow monarch enthusiasts report the scarcity of monarchs.
"Haven't see any this year," said one.
"Me, either," said another.
"No, not a single one," said yet another. "I'm looking."
Rita LeRoy has seen two at the Loma Vista Farm, Vallejo.
"Send some over to us," we said.
We remember butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, commenting at a meeting hosted at UC Davis Feb. 28, 2019 by the Environmental Defense Fund, that "monarchs are on life support." The attendees--some scientists, some citizen scientists--were there to discuss "Recovering the Western Monarch Butterfly Population: Identifying Opportunities for Scaling Monarch Habitat in California's Central Valley."
The organizers related that "The latest population surveys indicate that monarchs overwintering on the central coast have declined 86% since last winter and now total 0.5% of their historical average. Population declines have spurred greater scientific study, funding, and coordination around the western monarch. California legislators appropriated $3 million in funding to the CA Wildlife Conservation Board to establish the Monarch Butterfly and Pollinator Rescue Program."
"Additionally," they said, "the Western Association of Fish and Wildlife Agencies released a Western Monarch Butterfly Conservation Plan calling for an additional 50,000 acres of monarch-friendly habitat in the California Central Valley and adjacent foothills by 2029. Join Environmental Defense Fund along with farmers, restoration practitioners, and scientists for an invitation-only workshop to share expert knowledge and identify strategic opportunities for restoring monarch butterfly habitat across the Central Valley. We will discuss important topics including opportunities for monarch habitat in the food production landscape, incentivizing monarch habitat restoration using limited resources, production and distribution of native plants, and other subjects that will put the western monarch butterfly population on the path to recovery. We will use the results of the workshop to inform conservation initiatives and effectively and efficiently allocate funds and resources for optimal conservation outcomes."
Shapiro was one of the five speakers in the "State of the Science" workshop section. He has been monitoring Central Valley's butterfly population since 1972 and maintains a website on his research.
In his presentation, Shapiro declared that "monarchs are on life support in California, and we are reduced to prescribing placebos."
"Consider a doctor faced with a patient in rapid decline," Shapiro told the group. "All tests have failed to identify the cause. What is the doctor to do? You can't prescribe treatment for an undiagnosed illness, can you? You can make a wild stab at a prescription on the basis that the patient is going to die anyway, and MAYBE, just maybe, this drug will do some good. Or you can prescribe a placebo, just to reassure the patient that you are doing something. That's where things get interesting. Occasionally a patient improves drastically on a placebo. Maybe he would have improved anyway; there's no way of knowing. Suppose our patient has a complete remission despite having received only a placebo. Does our doctor convince himself the placebo cured him? As of right now, the Monarch is on life support in California, and we are reduced to prescribing placebos. If our patient comes back from the brink—as history suggests it may well—will we convince ourselves that our placebos worked? Probably. And that's not how to do science. That's what philosophers call the fallacy of post hoc, ergo propter hoc. We can do can do better than that!" (Read his presentation on a Bug Squad blog.)
Meanwhile, we know there's at least one monarch in Vacaville...Maybe it's a female and will return to lay eggs on our milkweed. We can only hope.
Have you ever seen the larva of a lady beetle (aka ladybug) dining on an aphid?
Lights! Camera! Action!
So here is this charming little immature lady beetle chowing down on an oleander aphid that has the audacity to infest the milkweed in our pollinator garden. Chomp! Crunch! Slurp! And then another aphid arrives on the scene. It does not flee. Aphids are not the smartest of insects.
Can you just wait! Hold on! I'm not finished eating this one, yet!
And then an adult lady beetle arrives. She ignores a fat aphid right before her very eyes. Shall we prey?
Can you just wait! Don't go away! I'll eat you when I'm hungry!
A lady beetle (it's not a bug, it's a beetle!) belongs to the family Coccinellidae. Scientists have described about 5000 species worldwide, and about 450 in North America.
How many aphids can a lady beetle eat in her lifetime of three to six weeks? An estimated 5000 aphids, according to the University of Kentucky Cooperative Extension Service.
That's great pest control!
One thing is for sure: the lady beetles and their offspring patrolling our milkweed plants will never experience famine. This is an all-you-can-eat buffet, and the aphids just keep on a'coming. They do not flee. Aphids are not the smartest of insects.
Now, where are the monarchs? We have milkweed waiting./span>
Especially those oleander aphids that suck the very lifeblood out of our milkweed plants that we're struggling to save for monarch butterflies.
Just call aphids "The Enemy of the Gardener" or "The Enemy of the Milkweed."
The University of California Statewide Integrated Pest Management Program (UC IPM) describes aphids as "small, soft-bodied insects with long slender mouthparts that they use to pierce stems, leaves, and other tender plant parts and suck out fluids. Almost every plant has one or more aphid species that occasionally feed on it."
"Aphids have soft pear-shaped bodies with long legs and antennae and may be green, yellow, brown, red, or black depending on the species and the plants they feed on," UC IPM tells us. "A few species appear waxy or woolly due to the secretion of a waxy white or gray substance over their body surface. Most species have a pair of tubelike structures called cornicles projecting backward out of the hind end of their body. The presence of cornicles distinguishes aphids from all other insects.
"Generally adult aphids are wingless, but most species also occur in winged forms, especially when populations are high or during spring and fall. The ability to produce winged individuals provides the pest with a way to disperse to other plants when the quality of the food source deteriorates."
Not only do aphids stunt plant growth but they can spread viruses. Plus, they produce that sticky honey dew they that attracts ants and other insects.
Density? We've seen aphids so dense on our milkweed stems that all we see is yellow. (Sometimes we see red!)
We recently saw them magnified on a Leica DVM6 microscope, operated by Lynn Epstein, UC Davis emeritus professor of plant pathology, at a demonstration in Hutchison Hall. (See image below)
In California, most aphids reproduce asexually throughout most of the year, according to UC IPM. Did you know that a single aphid can generate as many as 12 offspring a day--without mating?
Bring on the lady beetles (aka lady bugs), lacewings, and soldier beetles! The larvae of lady beetles and syrphid flies also do their part in gobbling up aphids.
What to do when biological control doesn't work that well? Or when your lady beetles depart? Pinch the aphids; spray them with with water; or spray them with a mixture of 1 tablespoon of dish soap (Castile liquid soap) and one quart of water. Some folks dab aphids with cotton swabs dipped in isopropyl (rubbing) alcohol but that will kill the monarch eggs and larvae as well. We've found that spraying a mixture of sudsy soap and water works best for us.
Lather is the best medicine.
Thar's gold in them thar hills?
Probably not. But thar's definitely gold in that there pollinator garden--our little pollinator garden in Vacaville, Calif.
Gold, black and white--as in the iconic monarch caterpillars.
We've been waiting all year for Mama Monarchs to lay some eggs on our milkweed. We planted four different species, watered them and watched them bloom, fade, and go to seed. The bees sipped nectar from the blossoms, aphids sucked the juices from the stems, lady beetles (aka lady bugs) ate the aphids, and milkweed bugs chewed on the seeds.
All was not going well.
At 9 a.m., we saw FOUR monarch caterpillars munching away on our potted narrow-leaf milkweed, Asclepias fascicularis. Then at 6 tonight, FIVE more on the same batch of narrow-leaf milkweed.
Just when I was thinking I wouldn't be rearing any monarchs this year (in 2016 the tally totaled 60 plus), one or more Monarch Mamas proved me wrong.
I placed the 'cats in a netted butterfly habitat from the Bohart Museum of Entomology to protect them from predators and give them a chance at life, a chance for another generation.
What's going on with monarchs in this area is not good.
Butterfly guru Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, who has monitored butterfly population trends on a transect across central California for 46 years, from the Sacramento River Delta through the Sacramento Valley and Sierra Nevada mountains to the high desert of the Western Great Basin, has not seen a single egg or caterpillar this entire calendar year at his low elevation sites.
"Not one!" he told Beth Ruyak on her "Insight with Beth Ruyak" program, Capital Public Radio, Sacramento, last week.
Shapiro, who maintains a research website at http://butterfly.ucdavis.edu, will talk about butterfly population trends (including monarchs) and how climate has affected them at a free public presentation from 6:30 to 7:30 p.m., Tuesday, Sept. 11 at Sierra College, Grass Valley. The event takes place in the Multipurpose Center Building, N-12, Room 103. Parking is $3; permits can be purchased at the kiosk machine at the main entrance to the campus. (For more information, contact the series coordinator, Jason Giuliani at firstname.lastname@example.org.)
And news flash: Shapiro spotted one monarch today, an adult female, in West Sacramento.