Saturday, November 23, 2019

Doctor Butterfly

Given my own hobby of taking butterfly pictures, and counting the number of species of butterflies I can find each year, I found this article interesting: This scientist has been counting butterflies for 47 years and has no plans to stop
Art Shapiro stands on the edge of a Chevron gas station in the north-central Sierra, sipping a large Pepsi and scanning the landscape for butterflies.

So far he’s spotted six species — a loping Western tiger swallowtail, two fluttering California tortoiseshells, a copper-colored Common checkered-skipper, a powdery Echo blue, a rusty-looking Nelson’s hairstreak and a brown Propertius duskywing.

And that was while waiting for his ride to finish up in the restroom.

Shapiro jots the names of each species on a white note card, then tucks it into his T-shirt pocket stuffed with three pens, one Sharpie, a glasses case and newspaper clippings.

It’s not a bad showing for a gas station at 7,000 feet, he says, climbing back into the car. Last year was abysmal for butterflies in California. For the first time in his life, he didn’t see one single monarch caterpillar all summer long. This casual count at the rest stop indicates that 2019 will be better. But Shapiro isn’t celebrating yet.

“Short-term fluctuations may or may not contain messages about longer-term trends,” he says. And the long-term trends are clear: In California, the butterflies are disappearing.

Shapiro, 73, is a professor of evolution and ecology at the University of California, Davis and a collector of many things: quotes, books, names and stories. Particular interests include Argentine politics, hermetic texts, meteorology and cheap beer. His specialty, however, is butterflies.

For nearly half a century he has meticulously tracked butterfly populations at 10 sites in north-central California, visiting each location every two weeks as long as the weather permits.

In that time he has single-handedly created the longest-running butterfly monitoring project in North America.

“It was originally designed as a five-year project, but the data were too good to stop collecting them,” he says. “And here I am, 47 years later.”

The protocol, for decades, has been unchanged and simple: Record and identify every butterfly he sees.

“It’s completely incomprehensible, the whole thing,” says Matt Forister, an ecologist who studied with Shapiro before starting his own lab at the University of Nevada in Reno. “Nobody visits 10 sites every two weeks for that long. It is unheard of in the history of science.”
This is really old school science that nobody funds anymore. I know of (and participated in) a similar long term study for crabs in our area, started by a scientist at my original old Academy of Natural Sciences lab in Maryland, looking at crabs off the shore here (1 site at CCNPP, and 2 nearby). George Abbe started it shortly after he came from Pennsylvania in the 1960s as a fresh student to work in Maryland for the ecological study for siting for CCNPP. He died recently (2013), but the project still goes on, in slightly modified form, as the longest running study of the relative populations of Blue Crabs in the Bay.

But back to butterflies. What has Shapiro found?
Shapiro climbs slowly over the rocky landscape. His quarry: a Brown elfin butterfly. “We’re looking for something that’s about the size of your thumbnail” he says, peering into a patch of low-growing huckleberry oak.

And then he sees them: Two copper-colored butterflies flitting around each other in chaotic circles. It’s either a mating ritual or a territorial battle. “Oh, we’re in luck,” he says, pulling out the white note card again. He adds “Brown elfin” to his list and looks up, pleased.

That makes 26 species of butterflies he’s seen today.
Henry's Elfin on our Eastern Hemlock 
That's pretty good! When I visit California, I'm lucky to find more than 5 different species of butterflies in a trip, and 2 of them are likely to be common continent wide species that I also see at home. We do have an elfin or two here, which put in brief appearances in early spring. They're small, cryptic, and if you don't get out to look when they're around, you miss them for the year.

One thing that might help in California is that they have a lot of variation in habitat over short ranges, and because a lot of butterflies are dependent on specific plants, there are many places to look for different species.

Here, I'm lucky to see 10-15 species on a good day in midsummer (mostly on my Butterfly bush), and accurately identifying all the different skippers is quite difficult.
Shapiro’s monitoring study was designed to focus on fluctuations on very short timescales — what scientists call noise. But as he kept monitoring the same sites decade after decade, a disturbing long-term trend emerged in his data.

Without a doubt, the overall abundance of butterflies was declining.

He didn’t notice it at first. Insect populations are volatile, plummeting in years when weather conditions are unfavorable and, because they can reproduce so quickly, rising when conditions are just right.

But in 1999, 27 years after Shapiro started monitoring his sites, something strange happened: the populations of 17 species of butterflies at his low-elevation sites tumbled all at once.

“That got my attention,” he says. “We had never had so many species go down at the same time before. And we began to look at long-term trends more carefully as a result.”

What he and his colleagues found is that if you eliminate the noise from his data, the number of butterflies had decreased significantly at these sites from when he first started his project.

In recent years it has gotten much worse. Forister, who does much of the statistical analysis of Shapiro’s data, said that back in the 1970s, Shapiro would regularly see 30 species at some of his sites. Today he is more likely to find 20.

Shapiro says 2018 was the worst butterfly season he ever experienced. The number of species across all elevations was down, something he had never seen before.

As a scientist, Shapiro knew this catastrophic count provided a valuable data point. The abysmal numbers could help other researchers understand how to make sense of future plunges in butterfly populations and perhaps help them pinpoint the culprit. But as a person who has spent his whole life among butterflies, he could not help but feel morose.

“One does not rejoice when one’s system is going away,” he says.

He told friends and colleagues that he felt like a physician who had known a patient for the patient’s entire life. Now the patient was obviously dying and he had no idea why.

Scientists who study butterfly populations blame a suite of factors for their decline, including loss of open spaces, changing agricultural practices and growing use of pesticides on farms and in home gardens. Statistical analysis also suggests that climate change has had an impact as well.
2018 was a bad year here, too, with 45 species identified total, compared to 52 this year.

But could age (his) be playing a role? Certainly your eyes don't get any better, and getting around gets harder.
Shapiro is in excellent health, but he can’t monitor the butterflies forever.

Public transportation to his sites has become more limited over the years, so he started recruiting student assistants to drive him to some of the more out-of-the-way locations, and serve as an extra pair of eyes.

“My vision is not improving with age,” he says.

A couple of years ago, he turned over his highest-elevation site to one of Forister’s graduate students. Hiking up the incline wasn’t a problem, but going down was wreaking havoc on his knees.

“Getting old is a pisser, but it beats the alternative,” he says.

There is no obvious successor to this work, and Shapiro says it is unlikely that other researchers could feasibly monitor his sites with the same consistency.

Forister and a handful of Shapiro’s other former students are working out how to keep the long-term data set going. One idea is to have an overlapping stream of graduate students take on his sites, each one training the next.

But it won’t be quite the same.

“The remarkable thing about Art’s data is that he did it, he did all of it,” Forister said. “I can’t do that. Honestly, I don’t know how he did that.”

For now, Shapiro has no plans to retire. His family’s medical history suggests he will drop dead by 83 if not sooner, he says.
Good luck to him!

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