The Familiar, the New, and the In-Between

by Carl Strang

As I approach the end of my 7-year stint of monitoring the natural history of Mayslake Forest Preserve, most of what I observe is familiar.

This longhorn beetle, Typocerus velutinus, is an expected visitor to the preserve’s flowers this time of year.

This longhorn beetle, Typocerus velutinus, is an expected visitor to the preserve’s flowers this time of year.

Likewise, this female azure bluet was not the first of her kind I have photographed on the preserve.

Likewise, this female azure bluet was not the first of her kind I have photographed on the preserve.

On the other hand, each week brings at least one new species to add to the preserve’s lists.

This moth is an example. The Vestal appears to be a simply white geometrid at first glance, but a closer look reveals shadings and highlights of yellow and gold.

This moth is an example. The Vestal appears to be a simply white geometrid at first glance, but a closer look reveals shadings and highlights of yellow and gold.

It also helps when someone else joins me on my walks. Nikki Dahlin is a beekeeper, and she is quick to point out the flower visitors.

This bee would not have drawn my eye. It seems unremarkable.

This bee would not have drawn my eye. It seems unremarkable.

Zooming out, however, reveals how tiny it is. There were dozens of these, ignoring the nectar of the wild bergamot flower tubes and focusing on the anthers and their pollen.

Zooming out, however, reveals how tiny it is. There were dozens of these, ignoring the nectar of the wild bergamot flower tubes and focusing on the anthers and their pollen.

I haven’t studied the native bees enough to know where to begin with an identification, which would be needed to access information on other aspects of this bee’s life. Another new insect for the preserve from last week is one I have encountered elsewhere, but wasn’t aware could be at Mayslake.

The rattler round-wing katydid usually stays out of sight during the day, but this female perched on her leaf as though basking in the intermittent sun.

The rattler round-wing katydid usually stays out of sight during the day, but this female perched on her leaf as though basking in the intermittent sun.

Another two weeks will bring my Mayslake chapter to a close, but in the fall a new one will open at St. James Farm.

 

Prairie Cicadas Ran Late

by Carl Strang

Prairie cicadas are very locally distributed in northeastern Illinois, and I have not yet found them in Indiana or Wisconsin. Their season is brief and variable, and so I rely on a population near my home, at West Chicago Prairie Forest Preserve, to tell me when they are active each year. This year has been a bust in my search for new populations. The largest number I counted at West Chicago Prairie was only 4, on July 12, and they were difficult to pick out among the many gladiator meadow katydids, whose briefer buzz has a similar sound quality. Usually the cicadas are finished before the gladiators become numerous. There were no cicadas singing in my final check yesterday.

Side view of one of this year’s few singers.

Side view of one of this year’s few singers.

Dorsal view of the same individual. These guys are little, about an inch long.

Dorsal view of the same individual. These guys are little, about an inch long.

At least some cicada species have the ability to postpone emergence by a year. Perhaps the rain or periods of cool weather at the beginning of the usual emergence period persuaded some of these to wait. If so, there may be increased numbers next year, and I will be able to resume my search for undiscovered populations.

Wing Length and Song Quality

by Carl Strang

In a preliminary way I have begun to look at the question of how wing length affects song production in Roesel’s katydids. This seems pretty esoteric at first glance, but it has personal practical application, as I will explain. Roesel’s katydid is a European import which first appeared in the late 1940’s around Montreal, Quebec. They since have spread to the point that they can be found throughout northern Indiana and Illinois, and at least much of Michigan and Wisconsin. They come in a variety of wing lengths:

Short, as in this female in Kendall County, Illinois…

Short, as in this female in Kendall County, Illinois…

Intermediate, as in this male recently photographed at St. James Farm…

Intermediate, as in this male recently photographed at St. James Farm…

And long, as in this male at Blackwell Forest Preserve.

And long, as in this male at Blackwell Forest Preserve.

Researchers have noted that long-established populations in the European homeland are composed almost entirely of shorter winged, therefore flightless, individuals. The frequent observation of long-winged variations here has fostered the speculation that this has to do with dispersal as Roesel’s katydid expands its North American range. That may be true in the long run, but the edge of that range is far from the Kendall and DuPage County locations of the above individuals, and long-winged ones remain common.

Since I began my study of singing insects in 2006, I have been disappointed to find that each year my ability to hear the buzzing song of male Roesel’s diminishes. Furthermore, on hot days I can hear them fine in the cooler morning hours, but at some point I can no longer hear them. The pitch of their song rises with temperature, until it goes above my audible range. The SongFinder pitch lowering device proves they still are singing (incidentally, the buzz is steady when I hear it unaided, but through the SongFinder it has a superimposed vibrato which becomes more rapid with increasing temperature. This doesn’t happen with other singing insects).

Over the winter the question came to me whether the wing length of the males affects their song. Next year, retirement will allow time to pursue this in more detail, but for now I have an afternoon’s observations that seem to support a difference. I was following trails through north Blackwell’s meadows, occasionally listening with the SongFinder. The temperature was mid-70’s F. Many Roesel’s were singing, but I would not have known this without the device. Then I heard one unaided. I sought it out, and it was long winged. The same was true of two other individuals (the third is the one in the above photo).

Next year I want to make recordings of individuals with different wing lengths, and compare the parameters of their songs. Perhaps the analysis also will give some idea why the pitch-altered song has that vibrato. I want to think, too, about the possibility that there is an evolutionary dynamic going on here. If the song is different among males with different wing lengths, does that matter to females? If so, how? For instance, if long-winged females prefer long-winged males, and short-winged females prefer short-winged males, this could retain genes for long wings in the population for a reason other than dispersal advantage.

 

Centennial Bioblitz

by Carl Strang

The Forest Preserve District of DuPage County’s Centennial Bioblitz started under rain and somewhat cool temperatures last Friday night. We sent off the first plant survey teams and frog monitors, and a small bird team went out, but the rain continued. As the darkness built, it became clear that light stations for insects would get limited results. I gathered the group who had come for one of the public programs, and Purdue University entomologist Jeff Holland explained that the dripping water would explode their hot bulbs. We set up my ultraviolet light, and Jeff led the team into the forest at St. James Farm.

Dr. Holland examines a beetle one of the participants found.

Dr. Holland examines a beetle one of the participants found.

The kids had a great time catching fireflies, and finding insects and other creatures active in the rain.

Classic kid nature fun was had by all.

Classic kid nature fun was had by all.

When we stopped by the light on the way back, we found a few beetles and small moths, but the sheet mainly held a host of mosquitoes.

Amid hundreds of floodwater and other common mosquitoes, there were a few huge ones.

Amid hundreds of floodwater and other common mosquitoes, there were a few huge ones.

Late into the night, and much of the next day, my focus was on support and organizational work, but I did make two brief field excursions and added a few species to the count on the four preserves of the bioblitz survey.

This green darner showed off its bullseye face paint.

This green darner showed off its bullseye face paint.

Halloween pennants have been common around the county in the past week.

Halloween pennants have been common around the county in the past week.

I recognized the chickweed geometer from my preserve monitoring work at Mayslake.

I recognized the chickweed geometer from my preserve monitoring work at Mayslake.

Roesel’s katydids had begun to sing in the previous week. This mature male has short to medium-length wings.

Roesel’s katydids had begun to sing in the previous week. This mature male has short to medium-length wings.

This coneheaded katydid nymph at the edge of the parking lot meadow was large enough, and its cone the proper shape, to be a sword-bearing rather than round-tipped conehead.

This coneheaded katydid nymph at the edge of the parking lot meadow was large enough, and its cone the proper shape, to be a sword-bearing rather than round-tipped conehead.

The botany teams no doubt caught this one, but I couldn’t resist photographing these starry Solomon’s plume fruits at Blackwell.

The botany teams no doubt caught this one, but I couldn’t resist photographing these starry Solomon’s plume fruits at Blackwell.

Our rough estimate at the end of the bioblitz was 900 species documented for the four preserves. I will report more detailed numbers when we have them.

 

Beauty in a Small Package

by Carl Strang

Working in one of my garden flowerbeds, I noticed a tiny critter with long hind legs. A glimpse was enough to interrupt the weeding and send me in for a camera.

He’s not even big enough to straddle a narrow daylily leaf. You can see why I wanted a photo.

He’s not even big enough to straddle a narrow daylily leaf. You can see why I wanted a photo.

With those legs, antennae, and colors, clearly this was a katydid nymph. But which one? A quick perusal of the BugGuide and Singing Insects of North America websites ruled out the species that I regularly have heard in my neighborhood block counts. It is a close match to photos identified as early-instar fork-tailed bush katydids, however. That makes sense for the neighborhood habitat, but I haven’t heard any here over the past couple of years. Or any other Scudderia species for that matter. I hope that this one, or a sibling, will survive to adulthood and sing so I can confirm their presence. This perhaps is a hint that I need to get in the business of rearing nymphs, like my esteemed Wisconsin and Ohio colleagues, Nancy Oecanthinancy and Lisa Rainsong.

Northern Wood Crickets

by Carl Strang

Those of you on the mailing list for my annually updated guide to the singing insects of the Chicago region would look in vain for northern wood crickets in last year’s edition. I simply wasn’t aware that they could be here. While preparing for the Hills of Gold bioblitz, however, I found that their range extends into our region. I had not included them in the hypothetical list because initially it was directed toward DuPage County in Illinois, and wood crickets never have been found in northeastern Illinois. I gained some experience with wood crickets in the bioblitz, and the sound recordings I made there proved to be of the northern wood cricket, Gryllus vernalis. Study of the relevant scientific paper (Yikweon Jang and H. Carl Gerhardt. 2006. Divergence in the callling songs between sympatric and allopatric populations of the southern wood cricket Gryllus fultoni [Orthoptera: Gryllidae]. J. Evol. Biol. 19: 459–472) indicated that the 2-chirp-per-second, 3-pulse-per-chirp, songs coming from leaf litter in forest habitat, were of northern wood crickets. Southern wood crickets, the other possibility, would have had faster chirps at that temperature.

Last week’s vacation survey trips went so well, despite two days lost to rain, that I had Saturday available to seek northern wood crickets the Indiana portion of the Chicago region (I had not found them in the Illinois, Wisconsin or Michigan excursions). My first two stops, in St. Joseph County’s Bendix Woods and Fulton County’s Judy Burton Nature Preserve, were fruitless. Mid-afternoon brought me to the Winamac State Fish and Wildlife Area in Pulaski County, and I drove the gravel roads until I found one of the parking lots in a forested spot. Immediately I heard the chirps of Gryllus crickets, and I dug out the Marantz sound recorder. As I recorded two different crickets I believed I was hearing 3 pulses in the chirps, as had been the case at the bioblitz.

This was where the cricket in the recording shared below was located.

This was where the cricket in the recording shared below was located.

I would have liked to try and flush out one of the singers, but as the photoflash lighting in the photo suggests, it was getting dark fast, and I barely reached the car before the downpour hit. I tried to get around the storm by driving to the Jasper-Pulaski Fish and Wildlife area, but no dice, and I had to call it a day. So, here is a cut of the stronger recording:

Can you distinguish the 3 pulses that form each chirp?

The visual rendition of the recording clearly shows the 3-pulse chirps, but they are being produced at a 4-chirp-per-second rate.

The visual rendition of the recording clearly shows the 3-pulse chirps, but they are being produced at a 4-chirp-per-second rate.

This might have been confusing, given that the southern wood cricket, not yet known from northern Indiana, more typically has a 4-chirp rate, but the soil temperature was very warm, at nearly 80F, and the scatter for vernalis in Jang and Gerhardt’s graph extends to 4 chirps at that temperature. Also, the dominant frequency was 5.9kHz, good for vernalis but pitched way too high for fultoni at any temperature. So, I am content for now that I have established a present-day northern wood cricket presence in the region. One goal for next year will be to seek them in more locations, make more recordings, and get a better sense of their song features in this part of their range.

Early Season Survey: South

by Carl Strang

On Wednesday of last week I drove south to seek early season singing insects in some Illinois counties.

My first stop was Richard Young Forest Preserve in Kendall County.

My first stop was Richard Young Forest Preserve in Kendall County.

The forest was empty of northern wood crickets, but there were several groups of an early season grasshopper.

They proved to be greenlegged grasshoppers. Though not in either singing grasshopper subfamily, they were beautifully colored and worth a little effort to photograph and identify. This is a mature male; the crinkly little wings are full sized for the species.

They proved to be greenlegged grasshoppers. Though not in either singing grasshopper subfamily, they were beautifully colored and worth a little effort to photograph and identify. This is a mature male; the crinkly little wings are full sized for the species.

The preserve’s prairie gave up county records for spring field cricket and greenstriped grasshopper.

The preserve’s prairie gave up county records for spring field cricket and greenstriped grasshopper.

I went on through Will County, adding a couple site records at the Midewin National Tallgrass Prairie, and also recording one of several puzzling ground crickets that sounded like striped ground crickets, and were in the appropriate habitat for the species, but were a month or more too early. I also checked the forest at Kankakee River State Park, but again failed to find any northern wood crickets.

Early Season Survey: North

by Carl Strang

On Tuesday of last week I drove north to seek early season singing insects in 5 Wisconsin and northern Illinois counties. I was prepared to camp overnight, but with rain in the forecast for the next day I was happy to complete the run in one day.

My first stop was Middlefork Savanna in Lake County, Illinois.

My first stop was Middlefork Savanna in Lake County, Illinois.

Spring field crickets were singing, but vegetation still was wet from an overnight rain, and I was lucky to spot this greenstriped grasshopper to give me that county record.

Spring field crickets were singing, but vegetation still was wet from an overnight rain, and I was lucky to spot this greenstriped grasshopper to give me that county record.

From that point it was rapid-fire site hopping, and I didn’t take many photos.

An exception was this Roesel’s katydid nymph at Wadewitz Nature Camp, a Racine County (Wisconsin) Park.

An exception was this Roesel’s katydid nymph at Wadewitz Nature Camp, a Racine County (Wisconsin) Park.

Wadewitz has extensive grassy meadows, and the biggest surprise of the day was not finding displaying greenstriped grasshoppers in the warm sunny mid-day. Ultimately I was able to find both spring field crickets and greenstripeds in all 5 counties, but several stops were required in some cases.

Early Season Survey: Berrien County

by Carl Strang

I took last week as a vacation to do some early season singing insect surveying across the Chicago region. Monday took me to Berrien County, Michigan, which I had searched only once before late in the season. In addition to seeking the few species active this early, I wanted to scout some sites for their later-season potential. My first stop was Galien River County Park.

The start of the trail looked promising. The forest proved to be of good quality. I listened for northern wood crickets, but none were there.

The start of the trail looked promising. The forest proved to be of good quality. I listened for northern wood crickets, but none were there.

The park’s most spectacular feature is a wonderful canopy walkway, which ends in a platform overlooking the Galien River and moderate quality wetlands.

The park’s most spectacular feature is a wonderful canopy walkway, which ends in a platform overlooking the Galien River and moderate quality wetlands.

The walkway takes you into the upper canopy. I’m looking forward to getting back some evening later in the season.

The walkway takes you into the upper canopy. I’m looking forward to getting back some evening later in the season.

The marsh is cattail dominated, with reed canary grass invading, but has some potential for wetlands singing insects.

The marsh is cattail dominated, with reed canary grass invading, but has some potential for wetlands singing insects.

Another site new to my experience was Mud Lake Bog. Bogs are few in the region, so I had high hopes.

I was not disappointed. A boardwalk winds a good length through a high quality bog.

I was not disappointed. A boardwalk winds a good length through a high quality bog.

There was plenty of sphagnum moss, so I expect to add Berrien to the short list of counties in the region still harboring sphagnum ground crickets.

There was plenty of sphagnum moss, so I expect to add Berrien to the short list of counties in the region still harboring sphagnum ground crickets.

A final stop for the day was Warren Dunes State Park. Spring field crickets were common in the more sheltered spots of the outer dunes.

A final stop for the day was Warren Dunes State Park. Spring field crickets were common in the more sheltered spots of the outer dunes.

An early season delight is to spot the glowing yellow of hairy puccoons.

An early season delight is to spot the glowing yellow of hairy puccoons.

No need to enhance the color in a photo of these beauties.

No need to enhance the color in a photo of these beauties.

Though the day produced only 2 county species records, it was delightful for visits to familiar sites and the promise of the new ones.

 

Hills of Gold

by Carl Strang

This year’s chapter in the bioblitz series organized by the Indiana Academy of Science was called Hills of Gold. It was on a beautiful site being assembled by the Central Indiana Land Trust, and when complete will occupy around 2 square miles in Johnson County, south of Indianapolis.

The event took place on an intermittently rainy day, as illustrated by this less than sharp image of a representative bit of forest and one of the old logging trails we used to get around the site.

The event took place on an intermittently rainy day, as illustrated by this less than sharp image of a representative bit of forest and one of the old logging trails we used to get around the site.

Usually my role in these bioblitzes is to survey singing insects, but this was too early in the season for a sufficient number of species to justify my participating. I decided to reconnect with my experience studying forest Lepidoptera ecology in the 1980’s, and took on moths as well. As I walked the forest during the day, I found many beautiful plants and animals outside my target groups that gave joy.

Green dragons always make me smile, and I ran across a magnificent cluster of them along one of the streams.

Green dragons always make me smile, and I ran across a magnificent cluster of them along one of the streams.

And who can say “no” to fire pinks? Hummingbirds sure don’t.

And who can say “no” to fire pinks? Hummingbirds sure don’t.

Violet wood sorrel is a plant I haven’t encountered very often.

Violet wood sorrel is a plant I haven’t encountered very often.

There also were insects to note outside my target groups.

This Bombus impatiens queen still had not found a nest site, and was prospecting the forest floor.

This Bombus impatiens queen still had not found a nest site, and was prospecting the forest floor.

I interrupted this female scorpionfly’s feed on an emptied caterpillar skin.

I interrupted this female scorpionfly’s feed on an emptied caterpillar skin.

Speaking of caterpillars, the first target species I found was this eastern tent caterpillar:

They already had reached the final instar and were starting to pupate.

They already had reached the final instar and were starting to pupate.

I collected only four moth species during the day. All were fairly common.

This was one of them, which I identify as the unadorned carpet, a member of the inchworm family.

This was one of them, which I identify as the unadorned carpet, a member of the inchworm family.

Many more moths came to my ultraviolet light setup that night. Stay tuned for that episode.

For the record, there was one singing insect. This was my first encounter with a wood cricket. I heard them scattered thinly all through the forest, but never succeeded in seeing one. They probably were northern wood crickets (Gryllus vernalis), but might have been southern wood crickets (G. fultoni). I made a couple good sound recordings, which I hope will allow me to make the determination.

One of them was singing from this patch of leaf litter.

One of them was singing from this patch of leaf litter.

More on that later, after I have analyzed the recordings.

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