Morgan Monroe-Yellowwood Ecoblitz

September 18, 2015 at 6:37 am (singing insects)
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by Carl Strang

The Indiana Forest Alliance is sponsoring a multi-year species survey of the back country portion of the conjoined Morgan Monroe and Yellowwood State Forests in Monroe and Brown Counties of southern Indiana. They are holding bioblitz weekends at various seasons so as to get a more complete picture than a single bioblitz would produce. Jeff and Mary Stant are providing the principal organizational and logistical support. I paid my first visit on September 12 to begin inventorying the singing insect species.

While waiting my turn to go into the survey area, I checked out the base camp in an old field with scattered young trees adjacent to the riparian edge of a wooded stream. The species mix was much like I would expect to find in a dry area in northern Indiana or Illinois.

Woodland meadow katydids were very common in woodland edges, much more abundant than I have found them farther north.

Woodland meadow katydids were very common in woodland edges, much more abundant than I have found them farther north.

The old field held scattered common meadow katydids.

The old field held scattered common meadow katydids.

Handsome trigs also were common in the riparian edge.

Handsome trigs also were common in the riparian edge.

Allard’s ground crickets were one of several species at the camp.

Allard’s ground crickets were one of several species at the camp.

The forested survey area was, as expected, less diverse, though the cool afternoon temperature probably inhibited some species. The slopes held scattered confused ground crickets, and bottomland herbaceous thickets were full of Say’s trigs, along with good numbers of Carolina ground crickets and more scattered jumping bush crickets and narrow-winged tree crickets.

At one point we flushed out a medium-sized cricket which permitted a quick photo but evaded capture. It was one of the camel crickets, probably in genus Ceuthophilus.

At one point we flushed out a medium-sized cricket which permitted a quick photo but evaded capture. It was one of the camel crickets, probably in genus Ceuthophilus.

We went up to a ridge top in the evening. It was very cold, and few species were managing to sing. There were scattered tinkling ground crickets, Carolina ground crickets, jumping bush crickets, and a few feebly ticking long-spurred meadow katydids. A background hum came from the forest canopy, and occasional individuals could be distinguished to support an identification of Davis’s tree crickets, by far the most abundant singers on that cold night.

I look forward to returning for more ecoblitz weekends next year.

 

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Gensburg-Markham Prairie

August 24, 2015 at 6:51 am (singing insects)
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by Carl Strang

One day last week I drove down to southern Cook County for singing insect survey work. I quickly found confused ground crickets for a county record in the Palos area, then proceeded to the Gensburg-Markham Prairie, which proved so fruitful that it occupied the rest of the afternoon. The dominant sound in that high-quality nature preserve was the buzzing of common meadow katydids.

The name is deceptive. This is one of the few places I have found to date where Orchelimum vulgare indeed is abundant.

The name is deceptive. This is one of the few places I have found to date where Orchelimum vulgare indeed is abundant.

There were other dry-habitat species present as well. I was able to add county records for woodland meadow katydid (my northernmost to date) and for straight-lanced meadow katydid.

This straight-lanced female was content to explore my finger and pose.

This straight-lanced female was content to explore my finger and pose.

The richest portion of the site’s singing insect fauna was the subfamily of stridulating slant-faced grasshoppers. I took lots of photos, thinking I had found the mother lode of species. When I examined them closely, however, the diversity turned out to be mainly within species, and I concluded that most of them in fact were marsh meadow grasshoppers.

Here is a classic adult marsh meadow grasshopper.

Here is a classic adult marsh meadow grasshopper.

But then there were a number of these. After much study I had to conclude that this, too, was an adult marsh meadow grasshopper.

But then there were a number of these. After much study I had to conclude that this, too, was an adult marsh meadow grasshopper.

Ditto for this one.

Ditto for this one.

Even more color variation was provided by nymphs. Again, I think they were marsh meadow grasshoppers.

This one in particular was strikingly colored.

This one in particular was strikingly colored.

And this individual seems aimed toward the pattern of the third adult above.

And this individual seems aimed toward the pattern of the third adult above.

These were my first of the species in Cook County, so they were a happy find. Two other grasshoppers also were my first for the county.

Wetter areas had plenty of short-winged green grasshoppers like this female.

Wetter areas had plenty of short-winged green grasshoppers like this female.

Prize of the day was this critter, the first spotted-wing grasshopper I have seen anywhere.

Prize of the day was this critter, the first spotted-wing grasshopper I have seen anywhere.

She wasn’t giving me good angles for photography, but fortunately I got a clear shot of the dorsal pronotum.

She wasn’t giving me good angles for photography, but fortunately I got a clear shot of the dorsal pronotum.

The inward-curving margins and their posterior big black triangles point to the two local species of Orphulella. There are two cuts in the dorsal surface, which point to O. pelidna rather than its close relative the pasture grasshopper O. speciosa.

This prairie is one I intend to visit in all portions of the singing insect season.

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Encounters Along the Way

September 23, 2013 at 6:04 am (singing insects)
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by Carl Strang

As another season of field research into the region’s singing insects winds down, I am starting to look back at the highlights. Some of these were chance encounters that provided new photo opportunities. For example, there was a weakened common true katydid I found on a trail at Waterfall Glen in broad daylight. I didn’t have a good photo of the species, and posed him after removing him from the hazardous trail.

Unfortunately I neglected to place his hind legs in a natural position.

Unfortunately I neglected to place his hind legs in a natural position.

Another species for which I want a better photo is the handsome trig. Some were singing on a cloudy day down in Fulton County, Indiana, and one came out in the open, but the low light resulted in a less than sharp image.

Tiny but colorful, the handsome trig lives in the southern part of the region I am surveying.

Tiny but colorful, the handsome trig lives in the southern part of the region I am surveying.

The Indiana Dunes area provided several photographs.

This oblong-winged katydid female was emitting single clicks in response to the more complex songs of nearby males.

This oblong-winged katydid female was emitting single clicks in response to the more complex songs of nearby males.

A four-spotted tree cricket had escaped from my grasp before I could photograph it. While looking for it on the ground where it seemed to have gone, my headlamp revealed something better.

A female tinkling ground cricket, only the second member of the species I have seen (despite hearing hundreds).

A female tinkling ground cricket, only the second member of the species I have seen (despite hearing hundreds).

A similar encounter came when I was trying to get a better photo of a melodious ground cricket at Indiana Dunes State Park. Digging through the leaf litter in the area from which a male’s song seemed to be coming, I turned up a female ground cricket.

When I examined the photos, though, I saw that the palps were white. This was a female confused ground cricket, another species that was singing in the area, and the first female confused I have seen.

When I examined the photos, though, I saw that the palps were white. This was a female confused ground cricket, another species that was singing in the area, and the first female confused I have seen.

One of the last places I visited this year was the Bong Recreation Area in Kenosha County, Wisconsin. The prairie area there is extensive, and has a good population of common meadow katydids.

Despite its name, the common meadow katydid is much less frequently encountered than two of its congeners, the gladiator and black-legged meadow katydids.

Despite its name, the common meadow katydid is much less frequently encountered than two of its congeners, the gladiator and black-legged meadow katydids.

There were a few broad-winged bush katydids in the prairie, but I wasn’t successful in stalking one. This Texas bush katydid had to substitute.

There were a few broad-winged bush katydids in the prairie, but I wasn’t successful in stalking one. This Texas bush katydid had to substitute.

Such encounters, sprinkled through the field season, make for good memories.

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Orchelimum Natural History

April 4, 2013 at 6:07 am (singing insects)
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by Carl Strang

Last week I made reference to Darryl T. Gwynne’s book on katydid mating system evolution. That book led me to other references, including a Ph.D. thesis by Marianne Feaver, who studied the behavioral ecology of three species of large meadow katydids (genus Orchelimum) under the direction of Richard Alexander at the University of Michigan in the 1970’s. I ordered a copy of Feaver’s thesis, and enjoyed reading it over the weekend. There was much richness of detail that will benefit my observations in the coming months and years. Here I’ll just share a few gleanings.

Male black-legged meadow katydid

Male black-legged meadow katydid

Feaver studied black-legged, common and gladiator meadow katydids. Maturation in the three species required 2 months from hatching to adulthood. In northeast Illinois the earliest species, O. gladiator, matures in late June, implying a late April hatch from eggs laid in the stems of plants.

Female gladiator meadow katydid

Female gladiator meadow katydid

Oviposition plants, food and cover are the three most important habitat features in these species. Upon reaching maturity, females move from nymphal areas that emphasize food and cover to places offering the best mix of food, cover and oviposition sites, and the males follow them there. The males then set up circular territories that space them out. These are defended mainly through song, though in high density populations physical combat often can take place. Defensive songs are characterized by increased number and rapidity of the tick portion of the song, the buzz portion apparently not important here. The territorial male reacts to the singing intruder, who may retreat or approach. In the latter case, after repeated warnings, the territory holder is likely to attack. The heavier male generally wins. Territory holding males tolerate silent males, which apparently are waiting for the territorial males either to be removed by predators or parasites, or to mate, after which they must retreat to gain back their weight.

Male common meadow katydid

Male common meadow katydid

They spend the night buried down in low, dense cover, then males begin spacing themselves out in mid-morning, and are singing by late morning. After territories stabilize, singing continues through the afternoon. Females assess and compare males, with mating taking place in the late afternoon. Females may take several days to choose a mate, however, and only mate once. In the early evening they break off to feed, then climb down into cover to spend the night.

This pattern provides a basis of comparison to other species, which will vary in detail. For instance, though I found a freshly mated female dusky-faced meadow katydid in the mid- to late afternoon, as I mentioned last week, that species reportedly does most of its singing at night.

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Toward Singing Insect Monitoring: Dominant Frequency

September 19, 2012 at 6:07 am (methods, singing insects)
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by Carl Strang

When I conduct workshops or lead field trips on singing insects, people commonly ask about monitoring protocols. We have well established monitoring programs in the Chicago area for birds, frogs, butterflies, dragonflies and damselflies, plants and probably other groups I am forgetting at the moment, so how about singing insects? My answer usually revolves around the fact that different people hear singing insects differently, and this obstacle is a challenge that has yet to be solved. An important variable here is that different people hear different ranges of sound frequencies, and commonly older folks (like me) lose the ability to hear high-pitched sounds. Recently I decided to try to get a quantitative handle on this pattern, using my experience as a gauge. I went to the Singing Insects of North America website and The Songs of Insects book by Elliott and Hershberger, and lifted out the dominant frequencies sung by the species in the Chicago region.

A male short-winged meadow katydid, one of the small meadow katydids, whose song has a dominant frequency of 13 kHz.

Most singing insects produce a range of different sound frequencies when they sing, a buzz for instance consisting of a mix of many low- to high-pitched sounds. Different sounds within the mix have different energies or volumes. The dominant frequency is the loudest one in a given species’ mix. Looking at just the dominant frequency, I see that the various local species range from 1.3 to 17 kilohertz (thousands of vibrations per second, a measure of the pitch or highness/lowness of a sound). I can hear every species with a dominant frequency below 13 kHz. In fact the only species I cannot hear at all are the small meadow katydids (the members of genus Conocephalus), which sing in the 13-17 kHz range. Children and young adults can hear these, I have found. A simple, if expensive, work-around is the SongFinder device.

The long-spurred meadow katydid is my marginal species, at 12 kHz. I can hear them from close range in the woods if there aren’t a lot of competing sounds. Interesting to me is the fact that I hear them clearly at the Brookfield Zoo, where they are fairly common. I doubt that the zoo’s long-spurreds have lower dominant frequencies. My best guess is that the relative lack of other sounds in that range, plus the amplification of the songs reflecting from sidewalks and buildings, increases my ability to hear them there.

Long-spurred meadow katydid, my marginal species

Another related variable is a person’s ability to pick up a sound from a distance. Roesel’s katydid has a dominant frequency of 15 kHz. I can still hear them, but less well with each passing year, and I have to be closer to them. Children and young adults easily pick them up earlier in the song and at a much greater distance. Probably what I hear is not that dominant frequency but the lower part of the frequency range included in Roesel’s buzz. Recently I learned that young adults can hear common meadow katydids, dominant frequency 10 kHz, at a much greater distance than I can, though I hear them clearly if I am within, say, 30 feet.

Common meadow katydid

I think that monitoring protocols are possible to develop, but clearly these are variables that will need to be taken into account. There are other obstacles as well, which I will address at another time.

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Braidwood Dunes etc.

September 13, 2011 at 6:10 am (singing insects)
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by Carl Strang

Last week I traveled to southern Will County to seek singing insects in sand country. My main stop was the Braidwood Dunes Natural Area, managed by the Forest Preserve District of Will County. I only got into part of it, and what I saw was outstanding.

There was an extensive dry prairie on sand soil dominated by little bluestem, for instance.

That prairie hosted the largest concentration of common meadow katydids I have encountered to date. In DuPage County I have found only scattered individuals and tiny groups.

It was a windy day, and the katydids were very shy. I took maybe 20 photos to get a couple that were only slightly blurry.

One of the species I specifically was seeking was the gray ground cricket. In places that were very similar in vegetation and soil to those where I heard this species at Illinois Beach State Park, I heard trills that sounded the same in memory.

One of the places where I heard probable gray ground crickets.

I made a recording, and cannot distinguish the sound, in trill speed or tonal quality or pitch, from that in a recording I made at Whitefish Dunes in the U.P. of Michigan a couple years ago (where the only candidate is gray ground cricket). Having no permit, I was not about to try and capture, let alone collect, specimens, so comparisons of recordings will have to do for now.

Otherwise, I heard mainly common species at Braidwood Dunes. I was happy to discover long-spurred meadow katydids in a wooded area, and I also made an observation that at first seemed trivial but later proved more substantive. It seemed that the Allard’s ground crickets were slowing their trill by a huge amount in shaded areas under trees. By the time I made the day’s final stop at Forsythe Woods Forest Preserve, I had realized that the slow ones might have been tinkling ground crickets, a sibling species of Allard’s. I made a recording of one there, and it proved identical in tonal quality and pitch, and in fact had a slightly longer spacing between notes, than the confirmed recording of a tinkling ground cricket by Lang Elliott and Wil Hershberger. This experience highlighted the emphasis here and there in the literature that the tinkling ground cricket is a species mainly of dry woodland edges.

My other stops were along the Kankakee River in my continuing search for variegated ground crickets.

I stopped first at a place with a long sandy river edge.

No ground crickets in the sand.

I also found a stretch with a significant pebbly shore.

The only ground cricket here was a single Carolina ground cricket. That’s it for seeking variegateds this year. Next year I may try for them in areas where they apparently are more concentrated, in southern Indiana. Once I have experience with the species, I may have a better idea of where to look in northeast Illinois.

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Common Meadow Katydid

August 26, 2009 at 6:40 am (singing insects)
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by Carl Strang

Earlier  I related my error in previously identifying DuPage County’s abundant, early-season large meadow katydid as the common meadow katydid, Orchelimum vulgare. This spring I discovered that the correct ID is the gladiator meadow katydid, O. gladiator. It turns out that the two are physically very similar, and there seemed to be some ambiguity in reference recordings of their songs. Last week I was at Meacham Grove Forest Preserve, mainly in search of late season Pachyschelus beetles, about which more will be forthcoming this fall or winter. Reaching Meacham’s west woods requires a walk across the meadow- and wetland-dominated eastern part of the preserve. Where the trail crossed the preserve lake’s inlet stream, I heard rattling buzzes that sounded like the songs of gladiators. This required some investigation, as gladiators elsewhere had finished singing weeks earlier. I found one, and it proved indeed to be a gladiator. But farther along the trail, approaching the pedestrian bridge over Bloomingdale Road, I heard a different song. This was a loud, tick-and-buzz Orchelimum song, but the ticks were more spaced and the buzz was very tight, making it distinct from the songs both of the gladiators I had just heard, and of the black-legged meadow katydids that also had been singing along the stream. This insect was in a dry meadow, singing from the exposed top of a sweet clover plant.

Common meadow katydid 2b

I photographed him, recorded his song, and then reluctantly collected him. He proved to be a common meadow katydid. The cerci, or reproductive claspers, are distinct from those of the gladiator and just like those in reference drawings for the common. The differences are, however, subtle enough under high magnification that I could not have confirmed them on the live insect. Another difference is the shape of the pronotum, the cape-like structure that covers the top and sides of the thorax. Here is the one on the common meadow katydid,

Common meadow katydid cropped 2b

and here is the one on the gladiator meadow katydid.

Gladiator cropped 3b

Again the differences are subtle, but the side of the gladiator’s pronotum has a simple, uniformly rounded outline with no major zigzags or kinks. That of the common meadow katydid has several turns or bends at the front, bottom and (especially) back edges. Incidentally, there is no mistaking a black-legged meadow katydid for either of the others if you see one:

Black-legged meadow katydid 2b

The best news out of all this is that the songs of these three large meadow katydids of DuPage County’s grasslands and wetlands are distinguishable. The gladiator’s buzz is a long, relatively slow rattling sound, with or without a few preceding ticks. The black-legged meadow katydid has a shorter buzz, of a similar sound quality but distinctly faster, always preceded by 2-4 ticks that are rapid, evenly spaced, and run straight into the buzz. Often, ticks and buzzes alternate in a continuous flow. In my limited experience since first finding the common meadow katydid at Meacham, I have noticed two variations in their songs. The buzz can be very tight and fast, reminiscent of Roesel’s katydid . In that variation the song is very different from both the gladiator and the black-leg. However, some individuals (perhaps ones singing at a lower temperature) have a slower buzz that to my ear is just like that of the black-leg. Confusion is prevented by attending to the ticks. In both common meadow katydid song variations, the ticks are irregularly spaced, farther apart, and more numerous than in the black-leg’s song.

For recordings that may help make these differences clear, check out the Songs of Insects and the Singing Insects of North America websites.

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Gladiator 1, Carl 0

July 13, 2009 at 6:11 am (singing insects)
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by Carl Strang

I wasn’t sure how I wanted to start this one. There’s an element of embarrassment, which might be good in a blog despite my personal discomfort. There’s the straightforward information approach, but that would leave out too much. This is a science-themed blog in the end, and I decided that perhaps that is where the emphasis should be. Science is not a body of knowledge. Science is a process, and it’s conducted by human beings, so it gets messy. Errors and false starts, egos and self deceptions all play an important and regular part.

Early in my study of singing insects, on 30 June 2006, I heard the year’s first meadow katydids singing in the dolomite prairie at Waterfall Glen Forest Preserve. I recorded the songs, took photos, and collected one. It was one of the large meadow katydids (genus Orchelimum).

Common meadow katydid 1b

It seemed to me that the habitat, the song, and the cerci (small clasping structures at the tip of the male’s abdomen) of the specimen best matched reference recordings and drawings of the common meadow katydid (O. vulgare). I posed the dead specimen to get a sharper photo than I had gotten of live insects in the grasses.

Common meadow katydid (dead) 3b

From that day until last Thursday I continued to treat these insects as common meadow katydids. The only odd thing about them seemed to be their infrequent inclusion of “ticks” in their song. That needs some explanation. There are a lot of meadow katydid species, and their songs have a tick-and-buzz pattern. Their wings have a sort of comb and file structure. Moving these together slowly produces separate “tick” sounds, vibrating them rapidly produces the buzz. A typical song begins with a few ticks, and ends with a buzz. The many species produce an impressive variety of variations on this basic pattern. All reference recordings of common true katydid songs included several ticks before the buzz. I wasn’t hearing them very often.

That brings the story to last Thursday night, when I presented a fireflies program at north Blackwell Forest Preserve. After I gave the interpretive talk to introduce the program, we walked to the nearby woods to see the light show. On the way we passed a large grassy meadow, in which there were a lot of katydids singing. Their songs were long rattling buzzes, and didn’t quite match familiar patterns. After the program was done I stayed, and found one of the singers to photograph.

Gladiator 3b

Clearly this is a large meadow katydid. In the process of stalking it I impressed the song on my memory. Back home I played my reference recordings, and found a perfect match in the gladiator meadow katydid (O. gladiator). My first feeling was elation, for this species was on my list of those which should be in northeast Illinois, but I had not yet found it.

The more I thought about it, though, the more questions arose. First, there were dozens of these insects in that meadow. How could I have missed them over the previous three years? Second, my impression from reading about gladiator meadow katydids was that they are a marsh species. What were they doing in an upland meadow? McKee Marsh is nearby, but many of these gladiators were singing a couple hundred yards above that wetland. I realized then that I needed to review references for both the gladiator and the common meadow katydid, because I may have identified these incorrectly from the beginning.

I listened, again, to all my reference CD’s and to recordings I had made of “common meadow katydids” in 2006. I found that there was a lot of variation in the reference recordings. All of the recordings attributed to gladiator meadow katydids had the rattling quality I heard Thursday night. Some of the recordings of common meadow katydids had a tighter buzz with no rattle, but others had the rattle, instead. The nighttime songs at Blackwell were very long buzzes, but the reference songs attributed to gladiators varied. Some were as long as those at Blackwell but others were short, like those of common meadow katydids. All of my own recordings proved to have the rattling quality, all had been made in daytime, all had the briefer length.

I had accumulated more books and articles since 2006, and I went through that material. For instance, Elliott and Hershberger in their recent book, The Songs of Insects (a link to their website is in my left blog frame), caution that the common meadow katydid is “Not nearly as common as its name implies” and that it is very similar in appearance to the gladiator. In their entry on the gladiator, they say that it is common, and describe its habitat as “tall grassy areas, often near water.” More enlightenment was provided by Alexander, Pace and Otte in their 1972 paper, “The singing insects of Michigan.” They indicate that the common meadow katydid is a late season species that “replaces” the early-season gladiator meadow katydid around the end of July or beginning of August. However, in Michigan they found the gladiator only in marshes.

Other references emphasized the physical similarity of the two species, to the point where males sometimes interact aggressively with one another (usually members of different species ignore each other). Furthermore, there were indications that they have different song variations for day and night.

So, armed with this information I returned to Blackwell Friday evening. I made a recording of the extended rattling song, and collected a specimen. A careful review of the new specimen and the one from 2006 forced me to conclude that both were gladiators. So, now I tentatively conclude that all the “common” meadow katydids I previously had recorded for July are in fact gladiators. In 2006 my last observation of this species was 25 July, in 2008 was 26 July, apparently ruling out the possibility of common meadow katydids in those years. In 2007 I have a couple notes from the first half of August, but by then the issue is confused by the presence of abundant black-legged meadow katydids (O. nigripes). These have a distinctive appearance, but a full tick-and-buzz song, so now I need to listen and look more carefully to large Orchelimum in August, because at the moment I have no unambiguous observations of common meadow katydids in DuPage County.

So, one lesson is to remember that in science, it’s a good idea to stay open to new information. In field work, look and listen freshly all the time for new things to notice. Hold onto your ideas lightly. Also, take all reference material with a grain of salt. In this case I found many ambiguities and contradictions even among refereed technical publications.

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Roesel’s Katydid Quest

June 30, 2009 at 8:43 pm (singing insects)
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by Carl Strang

Earlier I featured northeast Illinois’ common native predaceous katydid, the protean shieldback . We have another predaceous katydid, an import from Europe, Roesel’s katydid. Here is a female. Note the general brown color, and the yellow-edged half-moon of black behind the head.

Roesel's katydid female 2b

This is a species of open prairies, meadows and roadsides, preferring a mix of tall grasses and forbs. Here is a male in singing posture.

Roesel's katydid b

There are two things to note in comparing the two photos. First, the female is recognized by the curved, bladelike ovipositor protruding from the back of her abdomen. A structure of this sort is present in all female crickets and katydids. Second, note the long wings of the male and the short wings of the female. This is not a gender difference, as either gender can have either wing length. The male’s singing structures are in the basal part of the wings, and are complete in short-winged individuals.

Range maps for Roesel’s typically show it in a fairly large area of the northeastern U.S. plus a separate, smaller area in northern Illinois. I expected to find it in DuPage County. It is indeed abundant here, and I have found it in Kane and Kendall Counties as well. Imagine my surprise two years ago when, riding my bicycle around Culver, in north central Indiana, I started hearing the distinctive flat buzzing songs of Roesel’s katydids. I interrupted my workout to find one, and confirmed its identity visually. I intended to begin exploring the extent of their range extension last year, but a bike fall in mid-June gave me a broken collarbone and rib, forcing a postponement.

Last week I took a couple vacation days and searched for Roesel’s in two additional Indiana areas. First I drove to North Manchester in Wabash County, home of Manchester College.

Manchester College 3b

I covered 25 miles of country roads on my bike, and found scattered Roesel’s both west and east of North Manchester. I collected a voucher specimen.

Roesel's voucher b

I’m not fond of killing insects, but in this case felt the need for a voucher to support my claim. For what it’s worth, the greatest concentration of them was at the intersection of county roads 1400N and 300W.

Roesel coll site 2b

I found a larger than usual area of unmowed mixed grasses and forbs there.

Roesel coll site 3b

That was the source of the voucher specimen. The next day I drove down to Logansport for another prospecting bike ride. In a 22-mile tour of Cass County roads from the Wabash River north, again I encountered Roesel’s katydids regularly along the way. As on the previous day there were plenty of spring field crickets, too, plus a number of common meadow katydids, the first I’ve heard this year.

Roesel’s song is a mechanical sounding buzz, lengthy but with occasional interruptions. Nothing else produces a sound like it so early in the season. The males usually begin singing around mid-morning (though on a hot day I have heard them as early as 7:15 a.m.), and continue through the heat of the afternoon. In northeast Illinois the earliest appearance I have noted was June 10 (in 2007), latest June 22 (last year). They continue into the second half of July (the latest I have heard one was July 28 in 2006). For recordings of the song, go here  or here . You also can see the conventional range map, which clearly needs updating.

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