A Sept. 7 article in Reuters, headlined "Monarchs in Western United States Risk Extinction, Scientists Say," indicated that "Monarch butterflies west of the Rocky Mountains are teetering on the edge of extinction, with the number wintering in California down more than 90 percent from the 1980s, researchers said in a study published on Thursday."
Reuters' reporter Laura Zuckerman wrote that "The migratory monarchs of the western United States have a 63 percent chance of extinction in 20 years and an 84 percent chance in 50 years if current trends continue, according to the study."
The scientists, led by Washington State University conservation biologist Cheryl Schultz, published their work in the journal Biological Conservation. It was funded by the U.S. Fish and Wildlife Service, which is weighing the prospect of offering federal protection for monarch butterflies through the Endangered Species Act. The Xerces Society for Invertebrate Conservation is among those spearheading the effort.
Noted lepidopterist Arthur Shapiro, UC Davis distinguished professor of evolution and ecology who has studied butterflies, including the monarchs, for more than four decades, doubts that the western monarchs are teetering on the edge of extinction.
Shapiro, who maintains a website, Art's Butterfly World. says that yes, the western monarchs have been declining faster than the eastern monarchs, as per the Biological Conservation paper. However, during the drought, California populations appeared to rebound significantly, and it is not known whether the trend will persist, he says.
Their comprehensive and well-researched work, titled "Understanding a Migratory Species in a Changing World: Climatic Effects and Demographic Declines in the Western Monarch Revealed by Four Decades of Intensive Monitoring," was funded in part by the National Science Foundation. Their Oecologia abstract: "Migratory animals pose unique challenges for conservation biologists, and we have much to learn about how migratory species respond to drivers of global change. Research has cast doubt on the stability of the eastern monarch butterfly (Danaus plexippus) population in North America, but the western monarchs have not been as intensively examined. Using a Bayesia hierarchial model, sightings of western monarchs over approximately 40 years were investigated using summer flight records from ten sites along an elevational transect in Northern California."
"Multiple weather variable were examined, including local and regional temperature and precipitation. Population trends from the ten focal sites and a subset of western overwintering sites were compared to summer and overwintering data from the eastern migration. Records showed western overwintering grounds and western breeding grounds had negative trends over time, with declines concentrated early in the breeding season, which were potentially more severe than in the eastern population."
"Temporal variation in the western monarch also appears to be largely independent of (uncorrelated with) the dynamics in the east. For our focal sits, warmer temperatures had positive effect during spring. These climatic associations add to our understanding of biotic-abiotic interactions in a migratory butterfly, but shifting climatic conditions do not explain the overall, long-term, negative population trajectory observed in our data."
In acknowledgments, Shapiro and his colleagues thanked the Xerces Society for Invertebrate Conservation and the North American Butterfly Association for the monarch counts and making the data publicly available.
Meanwhile, since late August, the western monarchs (Arizona, California, Nevada, Oregon, Washington, Idaho and Utah) have been winging their way to their overwintering spots to forested groves along coastal California.
And then, around February, they will head inland to start the process again.
It's an amazing phenomenon.
As I write this, four monarchs are gathering some flight fuel, nectaring from two M's: milkweed and Mexican sunflower in our little pollinator garden in Vacaville, Calif., part of their migratory path to the coast. They flutter from flower to flower, seemingly unaware of the California scrub jay circling them and a photographer zeroing in on them. Or the rain about to fall.
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.
It's no fun having a "hole in one."
A hole in your butterfly habitat.
So, here it is September of 2016 and we're at home rearing monarch butterflies as part of our small-scale conservation project to help the declining population.
The project involves growing several species of milkweed in our pollinator garden, and when we see caterpillars, we "bring them in." We fill a broad-based, narrow-necked Patron tequila bottle with water, add milkweed and 'cats, and tuck the bottle inside a zippered, pop-up mesh habitat (some call it a cage) to protect them from predators (like birds) and parasitoids (like tachinid flies). The butterfly habitat occupies a corner of our kitchen counter.
So, one day in September, I think: "Why keep the monarch habitat on our kitchen counter when it's so nice and shady and breezy by the crape myrtle tree in our backyard?"
So, I place the habitat on a wooden bench next to the crape myrtle. Ah. Mother Nature at its finest. Several caterpillars are in the "J" position (their position before they pupate) and several are chrysalids.
All's right with the world, right? Wrong.
The unexpected happens. The caterpillars begin shriveling. The chrysalids turn gooey brown. And right before my eyes--I happened to be in the yard at the time--I see tachinid fly maggots "bungee jumping" from their hosts. The maggots are sliding down their white mucus strings. Gleefully sliding, I think.
Tachinid flies, you see, lay their eggs inside a living host, such as a monarch caterpillar or chrysalis. They eat the host from the inside out, kill the host, and maggots emerge. They're white at first but darken and harden to the color of coffee beans as pupae. The adult flies emerge, all ready to mate and start the life cycle all over again.
But how did they get into the thinly meshed habitat? How?
It is then that I notice a single, tiny, ragged hole in the netting. And oh, look! Another tachinid fly is trying to slip in.
I photograph Exhibit A, B, C and D; clean the cage with bleach and water; and vow that the butterfly habitat is best inside, not outside.
A hole in one is no fun.
Ready for those June weddings?
Coming to an altar near you...a bride and a groom. "When you marry in June, you're a bride all your life."--Anonymous.
"Look happy," say the wedding photographers as they focus on the bridal couple, and then single out the bride who will be a bride all of her life.
But if you engage in insect wedding photography, you'll find that June is a good month for insects, too.
Take those tachinid flies. Have you ever focused on them?
Monarch moms and dads--those who rear and release monarch butterflies--hate tachinid "weddings." They hate the bride, the groom, their families, and all future offspring. It's a hate-hate relationship.
That's because some members of the Tachinidae family are parasitoids, that is, the flies lay their eggs inside a living host (larva). The fly larvae eat the tissue from the inside out, killing the host.
That's good if you're trying to control cabbage white flies, cabbage loopers, alfalfa loopers, fall armyworms, variegated cutworms, codling moths, oriental fruit moths, peach twig borers, obliquebanded leafrollers, omnivorous leafrollers, oriental fruit moths, peach twig borers, pink bollworms and other pests. It's a "natural enemy" thing. See UC Statewide Integrated Pest Management Program.
That's bad if you're trying to rear monarch butterflies. You're appalled when your caterpillar shrivels and dies, and several fly maggots emerge. Or when your brown-stained chrysalis turns to goo, and out pop several maggots.
But back to insect wedding photography. We've never managed to catch tachinid flies feeling a little...uh...well...amorous. This amorous feeling is not mutual; to be honest, I still haven't forgiven them for what they did to our small-scale, rear-and-release monarch project last year.
Still, as a insect photographer, I consider myself a guest in their habitat.
So, yes, I walked away. I did. No insects were harmed in the making of these photographs.
Two icons, the American flag and the monarch butterfly, are flying high today.
The American flag, or "Old Glory," symbolizes our democracy. The 13 stripes represent the 13 colonies that declared--and won--independence from Great Britain. The 50 stars in the field of blue denote our 50 states.
The glorious monarch, Danaus plexippus, reigns supreme in the world of butterflies, in that it's the most recognized butterfly and its seasonal migration routes to its overwintering sites in coastal California and central Mexico--and its return every spring--are legendary.
How did it get its name? Swedish taxonomist Carl Linnaeus the father of modern taxonomy, named the butterfly "Danaus," for a great-grandson of the mythical Greek god Zeus, and "Plexippus," reportedly one of the 50 sons of Aegyptus, the twin brother of Danaus.
Fifty states. Fifty sons.
The common name, "monarch," is thought to honor "The Prince of Orange," who later became known as the King William III of England. (The butterfly is predominately orange and black.)
Fortunately, the majestic monarch butterfly isn't known as "The Prince of Orange" (or "The Princess of Orange.")