Long time passing
Where have all the flowers gone?
Long time ago
Where have all the flowers gone?
Girls have picked them every one
When will they ever learn?
When will they ever learn?"
The late folksinger and social activist Pete Seeger (1919-2014) sounded many alarms, but a recent article in the New York Times Magazine struck a different but somewhat similar chord: the declining population of insects worldwide.
Brooke Jarvis's piece on "The Insect Apocalypse Is Here," published Nov. 27, should be required reading.
Basically: Where have all the insects gone? What does it mean? Why haven't we noticed? And what are we going to do about it?
Well, butterfly guru/entomologist Art Shapiro, distinguished emeritus professor of evolution and ecology at the University of California, Davis, has noticed. Shapiro has monitored butterfly population trends on a transect across central California for 46 years and maintains a research website at http://butterfly.ucdavis.edu/. The 10 sites stretch from the Sacramento River Delta through the Sacramento Valley and Sierra Nevada mountains to the high desert of the Western Great Basin. Shapiro visits his sites every two weeks "to record what's out" from spring to fall. The largest and oldest database in North America, it was recently cited by British conservation biologist Chris Thomas in a worldwide study of insect biomass.
In her article, Jarvis related: "In October, an entomologist sent me an email with the subject line, “Holy [expletive]!” and an attachment: a study just out from Proceedings of the National Academy of Sciences that he labeled, “Krefeld comes to Puerto Rico.” (See news article on Krefeld's "Insect Armageddon.")
That entomologist was Art Shapiro.
Pesticides, loss of habitat, diseases, climate change, and human encroachment--and more--are some of the reasons why our global population of insects is dwindling.
Shapiro, who engaged in a 90-minute conversation with author Jarvis (and suggested topics and interviews for the piece), is quoted as having one of the few long-term data sets about insect abundance in the United States.
"In 1972, he began walking transects in the Central Valley and the Sierras, counting butterflies," Jarvis wrote. "He planned to do a study on how short-term weather variations affected butterfly populations. But the longer he sampled, the more valuable his data became, offering a signal through the noise of seasonal ups and downs. 'And so here I am in Year 46,' he said, nearly half a century of spending five days a week, from late spring to the end of autumn, observing butterflies. In that time he has watched overall numbers decline and seen some species that used to be everywhere — even species that 'everyone regarded as a junk species' only a few decades ago — all but disappear. Shapiro believes that Krefeld-level declines are likely to be happening all over the globe. 'But, of course, I don't cover the entire globe,' he added. 'I cover I-80.'"
Jarvis quotes plant ecologist Hans de Kroon of Radboud University, the Netherlands, as characterizing the life of many modern insects as trying to survive from one dwindling oasis to the next but with “a desert in between, and at worst it's a poisonous desert.”
Why should we care? As Jarvis succinctly points out: "Insects are the vital pollinators and recyclers of ecosystems and the base of food webs everywhere."
Now the concern should not only be "Where have all the insects gone?" but "What are we going to do about it?"
Butterfly expert Art Shapiro, distinguished professor of evolution and ecology, excitedly points to a Pipevine Swallowtail nectaring on roadside radish.
“Battus philenor! Battus philenor!”
It's the earliest he's ever seen the Pipevine Swallowtail in Gates Canyon, Vacaville, one of his 10 fixed study sites in California's Central Valley.
It is Saturday, Jan. 25. Another day to monitor the butterfly population, something he's been doing for 42 years. He posts much of his information on Art's Butterfly World.
Shapiro has trekked up Gates Canyon since 1976. He aims for 26 visits a year. In 2013 he totaled 32 visits. In a typical season, he finds approximately 30 to 40 butterfly species, "but that's not reached every year by any means," he points out. "Last year the maximum was 31."
It's a long way up and back. Shapiro, who doesn't drive a motor vehicle, rides a bus from Davis to the Vacaville bus station, then walks three miles from downtown Vacaville to Gates Canyon Road; up the road three miles and down three miles; and back to the bus station. That's a total of 12 miles.
Shapiro works his route easily. He's like an Olympic skater as he walks up the hill: hands folded behind his back and sometimes on his hips; eyes constantly sweeping for the count. He can, and does, detects the slightest movement, the slightest rustling of leaves, the slightest flutter of wings.
This Saturday Art Shapiro records eight different species of butterflies or a total of 18 individuals. And not just butterflies: he spots a yellow-faced bumble bee, Bombus voznesenskii, nectaring on radish next to a Pipevine Swallowtail.
Overall, it's a good day for "earlies." On Saturday, he sees his earliest Pieris napi, a Gray-Veined White, which beats his record of Jan. 31, 1984; his earliest Incisalia iroides, a Western Brown Elfin, eclipsing his previous records of Jan. 31 in 1976 and 1984; and his second earliest Erynnis propertius, Propertius Dusky-Wing, since Jan. 22, 1990.
Gates Canyon is bone dry. The thirsty hills and the dry creek beds ache for water. Alamo Creek, at the lower elevations, holds no water at all. At the higher elevations, the creek bed just trickles.
Shapiro's records shows that on Jan. 24, 1976, "under extreme drought conditions, I had 10 species flying at Gates Canyon. Today (Jan. 25, 2014), I had 8. Of these, only 2 were flying in '76." That amounted to 80 percent from what he detected on Jan. 24, 1976.
Shapiro keeps meticulous notes. His Jan. 25th notes include:
"Mid-70s, 90 percent sunshine (again, a few patchy altocumulus), light noth wind not getting into the upper canyon at all. No water in Alamo Creek at lower elevations; a bit more above than on Jan. 15, actually trickling audibly in spots. Vegetation little changed: alder and bay, nothing else in upper canyon (got up to ridgetop, where there is patchy bloom of manzanita and winter currant) except a totally anomalous native Lathyrus high on a sunlit, warm rock face, being visited by Battus (but I'm getting ahead of myself); somewhat more Raphanus down below, and very little Brassica. Aristolochia still dormant. The infamous 'poison oak tree' is leafing out but most poison oak is not. A few really small buckeyes are now in early leaf; hardly any green showing on big ones, even S-facing ones. No trace of Asclepias fascicularis. No Dentaria in flower and no detectable rosettes of Dodecatheon! Few birds. Still no Phainopepla. Deer and quail; no newts; no amphibian calls."
The 18 butterfly species he sighted at his Gates Canyon study site on Jan. 25:
- Battus philenor (Pipevine Swallowtail): 5 (new earliest at Gates)
- Polygonia satyrus (Satyr Anglewing): 1
- Nymphalis antiopa (Mourning Cloak): 5
- Celastrina ladon echo (Echo Blue): 3
- Pieris napi (Gray-Veined White): 1 (female-probably earliest ever)
- Incisalia augustinus iroides (Western Brown Elfin): 1
- Erynnis propertius (Propertius Dusky-Wing): 1
- Colias eurytheme (Orange Sulphur or Alfalfa Butterfly): 1
Shapiro worries about the drought. On Tuesday, Jan. 28, he recorded: "Today was the 52nd and last consecutive day with no rain in winter--a record probably never to be equaled in any of our lifetimes (I hope)."
Meanwhile, his other nine study sites in the Central Valley await him. They are all over the map, just as he is. As he says on his website: "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."
If you're lucky enough to accompany him on a survey, you'll hear him point out butterflies as excitedly as a winner yells "Bingo! Over here! Over here!"/span>
Butterfly expert Art Shapiro, distinguished professor of evolution and ecology at the University of California, Davis, monitors butterfly populations throughout the Central Valley, including Gates Canyon, Vacaville, Solano County.
Gates Canyon is one of his "stomping" grounds, or "monitoring" grounds.
And that's where we saw about half-a-dozen butterflies fluttering on Jupiter's Beard (Centranthus ruber), also known as Red Valerian. The perennial is native to the Mediterranean region.
The pipevine swallowtail (Battus philenor) is what Shapiro calls "the signature riparion butterfly of our region (Northern California), occurring along streams in foothill canyons and on the Central Valley floor, essentially everywhere its only host plant, California pipevine or Dutchman's Pipe, Aristolochia californica, occurs."
"This species is warningly colored and inedible to vertebrate predators," Shapiro says on his website. "It derives its protection from the toxic aristolochic acids produced by the host, which it sequesters; females even pass these along to the eggs, which are also protected (and are brick red, laid in bunches of up to 20, and quite conspicuous).
Brick-red eggs? That must be a sight and a delight to see!
You can read more about the pipevine swallowtail on his website.
The first time we ever saw a pipevine swallowtail, it was in the clutches of a hungry praying mantis. (See photo on my Flickr site.)
So it's good to see it "whole."