- Author: Kathy Keatley Garvey
It's not often you see "passion on passion."
That would be the "passion butterfly"--Gulf Fritillary, Agaulis vanillae--on the blossom of its host plant, the passionflower vine, Passiflora.
You often see the males patrolling the vine and the females laying eggs on the leaves.
But have you ever seen one foraging on a blossom?
On sunny days in Vacaville, we're seeing it happen more and more.
The brilliant orange butterfly with the silver-spangled wings is one spectacular butterfly. Together the passion butterfly and the passionflower live up to their names.
- Author: Kathy Keatley Garvey
Those passion flowers (Passiflora) are insect magnets.
One minute you'll see a praying mantis on a blossom. The next minute, a Gulf Fritillary, Agraulis vanillae. And the next morning, the blossom is an arthropod magnet--the beginnings of a spider web.
Passiflora is the host plant of the Gulf Fritillary, a spectacular orange butterfly with silver-spangled underwings. The Gulf Frit lays its eggs only on Passiflora.
The Gulf Frits know where the Passiflora is. Their predators know where the butterflies are.
The female mantis, Mantis religiosa (below), didn't snag the butterfly. But it did grab and munch on a few Gulf Frit caterpillars.
Ever critter eats in the garden.
- Author: Kathy Keatley Garvey
Will a praying mantis eat a caterpillar?
Short answer: Yes.
For several days, we've been watching a resident praying mantis, a female Mantis religiosa, hanging out in our patch of Passiflora (passionflower), the host plant of the Gulf Fritillary butterfly, Agraulis vanillae.
We grow Passiflora to attract these spectacular orange butterflies with the silver-spangled underwings. They sip nectar, court, mate and lay their eggs. The eggs hatch into hungry caterpillars and skeletonize our plants, which make us look like "bad gardeners" but the scenario makes for a "great butterfly habitat."
This year there's no "bad-gardener" look.
The caterpillars haven't skeletonized our plants.
Then we see Mrs. Religiosa. She does not look gravid, unlike the other mantids in our garden. She is string-bean thin. Praying mantis expert and UC Davis alumnus Lohit Garikipati figures she has already deposited her egg case, or ootheca, and she'll live another month or two.
Last year the Gulf Frits graced us with so many caterpillars that they were the zucchinis of the garden. Too many, too soon. We donated dozens of the 'cats to the Bohart Museum of Entomology, UC Davis, for its open house, and to youngsters engaged in science projects.
But this year, where are all the caterpillars?
In any pollinator garden, you must expect the pollinators, predators and the prey. Lady beetles and soldier beetles gobble up the butterfly eggs, while birds, spiders and wasps prey on the caterpillars.
We've never seen a praying mantis grab a caterpillar, though. Until now.
Oh, look! A butterfly ballet ever so graceful over the head of string-bean thin Mrs. Religiosa.
She ignores them. Then she spots a caterpillar. Easy catch, right?
Right.
Yes, a praying mantis will eat a caterpillar.
- Author: Kathy Keatley Garvey
It's Thursday afternoon, Aug. 20, and it seems like a good time to run a photo of a Gulf Fritilliary.
Because it just is.
It is a joy to see, especially when joy seems elusive as out-of-control wildfires ravage California.
As butterfly guru Art Shapiro, distinguished professor of evolution and ecology at UC Davis says about Agraulis vanillae on his website:
"This dazzling bit of the New World Tropics was introduced into southern California in the 19th Century--we don't know how-- and was first recorded in the Bay Area before 1908, though it seems to have become established there only in the 1950s. It can be quite common in the East and South Bay --particularly in Berkeley-- and has been found breeding spontaneously as far inland as Fairfield where, however, it is not established. There are scattered records in the Central Valley and even up to Folsom, perhaps resulting from people breeding the species for amusement or to release at social occasions. According to Hal Michael, who grew up in South Sacramento, this species bred there in abundance on garden Passiflora in the early 1960s. It seems to have died out by the early 1970s, however. Intolerant of hard freezes, it still managed to survive the record cold snap of 1990 that largely exterminated the Buckeye regionally!"
Its host plant: genus Passiflora or passion flower vine.
"In the Bay Area this species can be seen flying any day of the year, if it is warm and sunny enough," says Shapiro, who has been monitoring the butterfly populations of Central California since 1972 and posts the information on his website.
And if it's "warm and sunny enough," and you're growing Mexican sunflower (genus Tithonia rotundifolia), be sure to capture an image of a dazzling Gulf Fritillary nectaring on that equally dazzling blossom.
Both are a joy to see.
- Author: Kathy Keatley Garvey
It's commonly called a "passion butterfly," but we call it a Gulf Fritillary (Agraulis vanillaea) or Gulf Frit.
Or "spectacular."
A sure sign of autumn:
- A skeletonized passionflower vine (Passiflora)
- A Gulf Fritillary (Agraulis vanillae) eclosing
- A ravenous caterpillar crawling along a stem, and
- A caterpillar J'ing, about to form a chrysalis.
The orange-reddish butterfly, with its silver-spangled underwings, is a glorious butterfly.
How's the population doing this year?
Butterfly guru Art Shapiro, UC Davis professor of evolution and ecology, who has monitored the butterfly populations of central California for more than four decades and posts his research on Art's Butterfly World, says this year the Gulf Frit population is "spotty; locally abundant but less generally distributed than in recent years."
His 10 field sites stretch from the Sacramento River Delta through the Sacramento Valley and Sierra Nevada mountains to the high desert of the Western Great Basin.
We notice the ups and downs of the Gulf Frit population every year in Vacaville. This spring they were slow to start, Western scrub jays and European paper wasps grabbed what few caterpillars there were. In the summer, the population speeded up. And now caterpillars and chrysalids cover two of our three vines--or what's left of our three vines.
Shaprio says the Gulf Frit was introduced into southern California in the 19th century, in the vicinity of San Diego in the 1870s. It was first recorded in the Bay Area before 1908. "It became a persistent breeding resident in the East and South Bay in the 1950s and has been there since." Once prevalent in the Sacramento area in the 1960s, it "seems to have died out by the early 1970s," he said. Then in 2009, it began making a comeback in the Sacramento area.
Meanwhile, the passionflower vine climbs our fences with reckless abandon, only to be skeletonized by the growing population of Gulf Frits. They eat the leaves, the flowers, the fruit, and then start in on the bark.
More Gulf Frits mate. More eggs, caterpillars, chrysalids and adults appear. The cycle continues until the first frost. The plants die back, and will recover in the spring. A few chrysalids will remain, clinging to the vines like leftover Christmas tree ornaments,
Surprises occur. Several years ago, we saw a Gulf Frit laying an egg on Christmas Day.