It's not "officially" spring until we see--and photograph--the spectacular Western tiger swallowtail, Papilio rutulus.
One landed March 30 on an aromatic white lilac bush in Alamo Creek Park, Vacaville. It lingered long enough for a few photos and then fluttered away.
Butterfly guru Art Shapiro, UC Davis distinguished professor, Department of Evolution and Ecology, saw his first Papilio rutulus of the year on March 4 in Davis. Butterfly enthusiast and naturalist Greg Kareofelas, an associate of the Bohart Museum of Entomology, UC Davis, saw his first on March 23, also in Davis, "and since then, I've been seeing them regularly."
This butterfly's wings are a brilliant yellow with black stripes. Blue and orange spots accent "the tails" on their hindwings. The one we saw in Vacaville was missing some of its "parts," probably due to a close encounter with a predator, maybe a California scrub jay seeking a quick meal.
Professor Shapiro writes on his website: "The Western Tiger Swallowtail is basically a species of riparian forest, where it glides majestically back and forth along the watercourse. It has expanded into older urban neighborhoods where several of its host genera are grown as shade trees, and behaves as if the street were a watercourse. In the high country and on the Sierran east slope its usual host is Aspen."
"One brood (June-July) at higher elevations; one and a partial second at Washington; 2-3 at lower elevations with a long flight season (late February or March-September or October). An avid puddler. Visits Yerba Santa, California Buckeye, Milkweed, Dogbane, Lilies, Coyotemint, etc., etc. and in gardens frequent at Lilac and Buddleia. Spring individuals are smaller and usually paler than summer. Low-elevation hosts include Sycamore (Platanus), Ash (Fraxinus), Cherry and other stone fruits (Prunus), Willow (Salix), Privet (Ligustrum), Lilac (Syringa) and (in Sacramento County) Sweet Gum (Liquidambar)."
Shapiro has monitored butterfly populations across central California for more than 45 years. It's part of his continuing effort to regularly monitor butterfly population trends on a transect across central California. "Ranging from the Sacramento River delta, through the Sacramento Valley and Sierra Nevada mountains, to the high desert of the western Great Basin, fixed routes at ten sites have been surveyed at approximately two-week intervals since as early as 1972. The sites represent the great biological, geological, and climatological diversity of central California."
And one of the species is the spectacular Western tiger swallowtail, which Shapiro monitors at all 10 of his sites.
Butterfly guru Art Shapiro, UC Davis distinguished professor of evolution and ecology, knows where they are. As mentioned in a previous Bug Squad blog, he spotted a cabbage white butterfly, Pieris rapae, on Jan. 16 on the UC Davis campus, just south of the Jan Shrem and Maria Manetti Shrem Museum of Art, located at 254 Old Davis Road.
As you probably know, Professor Shapiro always looks for rapae as part of his scientific research; he sponsors the annual Beer-for-a-Butterfly Contest to determine its first flight of the year. COVID-19 canceled this year's contest.
But did you also know that Shapiro found FOUR other butterfly species on his Jan. 16th rounds in Davis, which included Old Davis Road on the UC Davis campus, and residential Davis?
- Red Admiral, Vanessa atalanta, seen in Lot 1 landscaping
- Gulf Fritillary, Agraulis vanillae, spotted in residential Davis, north central
- West Coast Lady, Vanessa annabella, seen on Old Davis Road near the campus hotel.
- Mourning Cloak, Nymphalis antiopa, spotted on Old Davis Road
The links on the species will direct you to his amazing research site, Art's Butterfly World, and the wealth of information.
Our butterfly-spotting record so far: Zero. Zilch. Nada.
But of course, what with the pandemic and all, we haven't been out much. The 100-acre UC Davis Arboretum and Public Garden is a good place to stroll, observe and photograph. We remember spotting a Mourning Cloak in the Arboretum's Ruth Risdon Garden on Saturday, Feb. 6, 2016 on an identification sign for the silver anniversary butterfly bush, Buddleia “Morning Mist."
It was a good place to warm its wings.
Meanwhile, here are a few images of the butterflies that Shapiro saw on Jan. 16. These images were taken in the two-county area of Yolo and Solano.
Suds for a bug! What could be better than that?
It's all part of Shapiro's scientific research to determine the bug's first flight of the year. The good professor, who launched the contest in 1972, maintains a research website at http://butterfly.ucdavis.edu/.
It's a little too early to start thinking about cabbage white butterflies, but it wasn't too early for a jumping spider.
For several weeks, we've been admiring a jumping spider hanging out on our Mexican sunflower (Tithonia rotundifolia). Monarchs, Western tiger swallowtails, buckeyes, gray hairstreaks, cabbage whites and assorted other butterflies nectar on it. Our jumping spider (we've named him Herman to distinguish him from the other jumping spiders in our pollinator garden, and besides jumping spiders ought to have a name), nails his share of prey.
So here we are, enjoying a sun spurt on Oct. 30 when a cabbage white butterfly tumbles off the flower as if it were on a bungee cord. A closer look: The butterfly was not alone.
Can jumping spiders win the Beer-for-a-Butterfly Contest?
It's not that Herman was just a little bit too early, and the butterfly was just a little bit too slow. Nope.
To claim the prize, you have to deliver the specimen to the UC Davis Department of Evolution and Ecology office at 2320 Storer Hall. Herman neither knows where that is, nor does he care. Plus, the specimen has to be alive, and Herman made sure it wasn't.
Rising from the Ashes--Some Day
People ask me all the time where butterflies go when it rains. Now they're asking me where they go when it burns.
In a word, to the Elysian fields. They have nowhere else to go!
The unprecedented wildfires have destroyed very important butterfly habitats in 2020, particularly in the High North Coast Range where a million acres – mostly in the Mendocino National Forest – have burned. We have been doing biogeographical survey of the butterfly faunas of this region beginning in 1974. Earlier fires largely removed the fir forest from the upper reaches of Snow Mountain (summit 7056'), leaving it covered in successional montane chaparral. But Goat Mountain (6112'), Hull Mountain (6831'), Anthony Peak (6958'), and Black Butte/Mendocino Pass (7455') still had many intact plant communities containing rare and relict species (many of which were isolated and far-removed from their core ranges in the Sierra Nevada and/or the Klamath Mountains). These included very rare wet meadows (as at Plaskett Meadows near Mendocino Pass) and treeless “balds” on rocky summits, usually facing southwest, producing a simulacrum of alpine fell-fields typically found several thousand feet higher.
We had documented roughly 115 species of butterflies in these places. Some, like the Nevada Arctic (Oeneis nevadensis) and the Arctic Skipper (Carterocephalus palaemon) were at their southernmost range limits, not just in the Coast Range, but globally. One butterfly new to science, the Bald Hills Satyr (Cercyonis incognita), was discovered at mid-elevation on Goat Mountain (100% of which burned) and in a few spots farther north. All of its known habitats may have burned—we won't know until we can get in, not before next year—and it is possible that it is extinct. In addition, we discovered that the widespread, familiar Pine White (Neophasia menapia) was apparently two sibling species on Goat Mountain and near Seven Troughs Spring in the Mendo Pass area, flying several weeks apart and with morphological differences. We did publish that one! All the known localities for the late-season entity have burned, too. This situation is of special interest because the idea that species could originate through temporal isolation has been discussed for many decades, but rarely if ever firmly documented. (The classic case, in field crickets, has been falsified by DNA analysis.) We have to be thankful that we got the data we did before the holocaust. Now, of course, the pressure is on to digest it.
Recovery of the butterfly faunas cannot occur until the vegetation resources they depend on come back—and they may never do so. Glacial relics, like the unique four-petaled Plaskett-Snow Basin race of the bog shooting-star Dodecatheon jeffreyi –personally, I think it deserves species status—may never come back. Nor many of the stranded alpine and edaphic (soil-specialist) species, because they are so far from any conceivable seed source. We have to hope they have persisted in the soil seed bank and may in time recover. Only then can the butterflies re-establish—if there are sources of potential colonizers. The farther any unburned sources and the weaker the dispersal capabilities of the butterflies, the longer the lag times to recolonization. Only the most vagile and broadly-adapted species are likely to recolonize a burned area of a million acres anytime in the next half-century or more.
The fires of 2020 were fed by the combination of 60 percent of recent mean precipitation in the 2019-2020 rainfall year and extraordinary evapotranspiration demand on the vegetation resulting from the hottest late summer on record. Yes, climate change is real. And our Coast Range butterfly faunas may never be the same again.
- Sympatric, temporally isolated populations of the pine white butterfly Neophasia menapia, are morphologically and genetically differentiated, PLOS ONE, published May 31, 2007. Authors: Katherine L. Bell, Christopher A. Hamm, Arthur M. Shapiro and Chris C. Nice, https://doi.org/10.1371/journal.pone.0176989
- A New Species of Cercyonis (Lepidoptera: Satyridae) from Northern California, Bulletin of the Allyn Museum, Florida Museum of Natural History, published Sept. 5, 2012. Authors: John F. Emmel, Thomas C. Emmel and Sterling O. Mattoon
Contact: Art Shapiro at email@example.com
Shapiro says that "Although it is a significant alfalfa pest, this butterfly overwinters as a larva almost entirely in annual vetch at low altitudes, and colonizes alfalfa only as the vetch senesces in May-June. Aside from alfalfa and annual vetches, it also breeds on a variety of clovers and sweet clovers and occasionally on lupines."
"Caterpillar populations usually result from a flight of butterflies into the field when the alfalfa is less than 6 inches tall," according to UC IPM. "Extremely large numbers of adults migrating between fields are often present from June to September in the Central Valley and from May to October in the southern desert. Factors contributing to economically significant caterpillar numbers are:
- Slow and uneven growth of the crop
- Lack of natural enemies
- Hyperparasites (other parasitoid wasps attacking the natural enemy wasps reducing their numbers)
- Hot, dry weather.
"There are four to seven generations per year of alfalfa caterpillar, and each generation is closely synchronized with the hay-cutting cycle so that the caterpillar pupates before cutting occurs." See more information on the UC IPM website.