Monday, July 1, 2019

Nature: Dragonfly rarities pop up in survey

A young male Paiute dancer (Argia alberta) at Cedar Bog/Jim McCormac

June 30, 2019

NATURE
Jim McCormac

The Ohio Dragonfly Survey, which began in 2017, is in its third and final season of field work, and mountains of records have been contributed by scores of volunteers. More than 43,000 individual observations have been submitted by about 1,100 contributors.

So far, about 165 odonata (dragonfly and damselfly) species have been documented in the state. Most are common, at least regionally, and make up the bulk of records. The top five most frequent species are eastern pondhawk, eastern forktail, blue dasher, fragile forktail and common whitetail.

Those damsels and dragons are low-hanging fruit. Important to document, but easy to find. However, it’s the rarities that really get dragon hunters pumped. Some utterly unexpected species have turned up during the survey.

I crossed paths with one of these new Ohio odonates recently at Cedar Bog near Urbana in Champaign County. Last year, uber-dragonflier Jim Lemon found Ohio’s first record of Paiute dancer (a damselfly) in a Clark County fen. He went on to document more dancers at Cedar Bog, and Sarah White located a Greene County population.

The beautiful Paiute dancer resembles a few species common here. Lemon, who has contributed nearly 7,000 observations to the dragonfly survey so far, went back through his old photos. He unearthed Paiute dancer images from Cedar Bog dating to 2014, mislabeled as common look-alike species. Many of the state’s dragonfly experts had apparently passed them by for at least several years at the heavily studied Cedar Bog.

That this insect would occur here was a shock. There is only one other small population west of the Mississippi River, in central Indiana. One must travel 500 miles to Missouri before Paiute dancers become reasonably common. The core of the range is much farther west yet: the Great Basin region of Arizona, California, Nevada and Utah.

Although we can’t be sure of how long the Paiute dancer has occupied Ohio, there are other, more clear-cut recent range expansions. Lemon also discovered our first jade clubtails last year in Auglaize and Shelby counties. A species of the Great Plains, the Ohio population is the easternmost record.

Lemon also found Ohio’s first swift setwing in 2014 in Champaign County, and he and others have located populations in eight additional counties since. This distinctive, conspicuous dragonfly’s main range is the southern one-third of the U.S. south into Central America.

Survey coordinator MaLisa Spring located double-ringed pennants this year in Jackson County in southern Ohio. No one anticipated this discovery; this beautiful dragonfly normally occurs well south of Ohio.

Nina Harfmann found the little blue dragonlet this year in Jackson County. No one had seen one in the state since 1933, the only prior record. It, too, is a species of the far south.

Several damsels and dragons have staged massive immigrations into Ohio in the past few years, all southern species. They include blue-faced meadowhawk, great blue skimmer, lilypad forktail and slaty skimmer.

Dragonflies are powerful aerialists capable of quickly expanding ranges when favorable changes open new opportunities. In 2001, dragonfly expert Dr. Dennis Paulson published a paper titled “Recent Odonata Records from Southern Florida — Effects of Global Warming?” Perhaps we could ask Paulson’s question here, now.

For more information about the Ohio Dragonfly Survey, visit u.osu.edu/ohioodonatasurvey or contact Spring at spring.99@osu.edu.

Naturalist Jim McCormac writes a column for The Dispatch on the first, third and fifth Sundays of the month. He also writes about nature at www.jimmccormac.blogspot.com.

1 comment:

Anonymous said...

I am just curious, is the dragonfly population in decline as with the general insect population that has recently been documented?