At dark, a crowd seeks out New Hampshire moths

  • More than 40 people showed up for a mothing event at the Harris Center. Among the moths drawn to lights: a tufted bird-dropping moth. No mystery where that name came from. Photo by Francie Von Mertens

  • Over 40 people showed up for a mothing event at the Harris Center. Photo by Francie Von Mertens

The Backyard Birder
Thursday, July 12, 2018 11:11AM

Moths. A growing number of people go “mothing.” I often ask eager birders what got them going down the birding path, and for some it’s a spark bird.

I suspect the lovely luna moth sparked many moth seekers, curious about other amazing creatures of the night.

At a moth presentation Saturday night at the Harris Center, the meeting room was full of people eager to know more about the moth world.

All ages. The curiosity, energy and enthusiasm of the youngest held strong until past just about everyone’s bedtime hour, matched only by presenter Sam Jaffe’s curiosity, energy and enthusiasm.

Founder of The Caterpillar Lab in Marlboro, Sam and Lab Manager Jesse Varga had done a lot of set-up before the group arrived at 8.

First off, indoors, we examined branches they set in water jars.

Large green caterpillars against green leaves were easy to find, but only because we knew they were there. Cards ID’d them as luna and polyphemous moth caterpillars. Sam also brought along adults of both, beauties both.

Mottled gray caterpillars flattened against a mottled gray oak branch were impossible to find. Same for caterpillars that looked like small twigs, two inches long, angled out just like a twig and with an rough-edged end that looks like a snapped off twig.

Such brilliant mimicry. How does that happen?

All were found in Sam’s backyard, also in Marlboro. Our backyards. So much goes on. . .

His slides of caterpillars and moths, portraits, really, against a white background, point to a huge diversity of moths – some 5,000 moths compared to about 130 butterflies in New England.

As the slides progressed, Sam talked about moths with venomous hairs and other chemical defenses, regurgitation included, or bright colors that suggest – or deliver – toxicity as predator-avoidance ploys beyond mimicry.

At 9 p.m., we headed out to see what two mercury vapor lights had attracted, directed at white cloths hung like sheets on a clothesline. Sam said for backyard moth seekers, compact fluorescents work, too. Or any old light.

Amazingly, we don’t know why lights lure moths and other insects. Various theories are easily debunked. What is known: Shorter wavelength UV attracts the most.

Indeed, clouds of insects were drawn to the mercury vapor lights. Sam inhaled a few as he ID’d moths drawn to the light, or gave natural history insight about moths, the plants they associate with, conservation, and population trends.

Inhaling one more gnat or mosquito, he said their activity period would end soon and the “best” moths would show up, a few hours after full dark – not the in-between mosquito hour.

As with birders, moth people keep yard lists, and Sam decided to have what a birder would call a Big Year last year.

Suffering sleep deprivation, he stopped in August with 860 species. He cited a more sleep-deprived fellow in Massachusetts with a yard list of 1,300.

A lot of committed moth seekers attend an almost annual Mothapalooza event in Ohio, where Sam is a regular presenter.

He said his favorite “show” is a street corner pop-up where he reaches people who probably wouldn’t attend a moth presentation at a nature center. As a populist moth seeker, he clues people in to the workings of nature through moths, ordinary, extraordinary moths, insects that people might have an aversion to as they whack around porch lights and streetlights.

As for how moths are doing, as with all insects their numbers are declining rapidly. Relating to that, birds that eat winged insects are the most rapidly declining group of birds.

The usual suspects include pesticides, no surprise, including spraying for mosquitoes, but New England moths have another challenge.

To combat gypsy moths and their impact on forests, a tachinid fly was imported in 1906 that is a parasite to gypsy moth caterpillars. Tachinids lay eggs on caterpillars that hatch into larvae that feed on their host. Lethally.

It’s not a picky parasite, and when the gypsy moth caterpillar cycle ends, or in years of little to no outbreaks, it lays eggs on native moth caterpillars. Of course.

Yet again, native species have no effective defense against an introduced species.

There was some talk about moths as pollinators. Sam cited their value. Some moths evolved along with a particular plant species, and as its main pollinator are essential to that plant’s survival – and vice versa.

But overall it’s native bees that get the job done. Actually, that’s me talking, not Sam, and to make my point, you don’t ever hear “Busy as a moth.”

Moths feed on nectar only, and only to meet their own needs. They don’t buzz from flower to flower, gathering pollen and nectar to take back to their colony to provision the next generation. Back and forth, daylong.

Instead, moths fill up, and as low-metabolism animals that doesn’t take many flower-to-flower visits. With really, really long tongues, they don’t need to get really close to a flower’s pollen-bearing anthers.

But back to moths.

My favorite is pictured here, a tufted bird-dropping moth, not a small bird-dropping moth, or an exposed bird-dropping moth, or a chalky bird-dropping moth, or an owl-eyed bird-dropping moth.

Evidently a number of adult humans had trouble getting away from poop when naming moths.

Recommended: A visit to The Caterpillar Lab in Marlboro. Check the website for hours and presentations. It’s a testament to what a person with vision and passion can create.

He’s out to save the world. We need insects, fundamental to life on earth.