The Magic Swale

by Carl Strang

After a summer that seemed dominated by rain and cool weather, late September brought a period of sun and warmth, offering hope of salvaging a field season that had been, on the whole, uninspiring. The Bendix Woods bioblitz brought some good results, and I was happy with my experiences at Midewin and Indiana Dunes National Lakeshore, so things were looking up. On my next stop I was passing a swale when I heard some curious songs through the SongFinder pitch-lowering device that led me to pause.

It doesn’t look like much in the photo, but this wet-bottomed depression had one quality increasingly hard to find in a wetland: a lack of invasive marsh plants.

It doesn’t look like much in the photo, but this wet-bottomed depression had one quality increasingly hard to find in a wetland: a lack of invasive marsh plants.

Long-tailed meadow katydids, not an everyday insect, were a good find, but they were not producing the mystery song.

Long-tailed meadow katydids, not an everyday insect, were a good find, but they were not producing the mystery song.

Reportedly a common species, the marsh meadow grasshopper had evaded my wish for a photo op until this day.

Reportedly a common species, the marsh meadow grasshopper had evaded my wish for a photo op until this day.

One of them stridulated before my eyes, rapidly raising and lowering its hind legs to scrape against the folded wings, producing the characteristic zuzz-zuzz-zuzz… of the slant-faced stridulating grasshopper subfamily.

The marsh meadow grasshopper provides yet another variation in the structural beauty of grasshoppers. The little rectangular shape above the antennae is one of the diagnostic features of this species.

The marsh meadow grasshopper provides yet another variation in the structural beauty of grasshoppers. The little rectangular shape above the antennae is one of the diagnostic features of this species.

Eventually the SongFinder led me to the singers in the swale. They will endure as the highlight of this year’s field season.

Stripe-faced meadow katydids!

Stripe-faced meadow katydids!

This is a species I have sought for years. The hints in the literature are vague in some ways, contradictory in others. I have slogged through marshes, bogs and marl in counties throughout the Chicago region, and yet here, where I would not have expected to find it, was a population of Orchelimum concinnum. They were beautiful, like the other wetland members of their genus, and well named with that ornamental stripe down the front of the head.

The stripe is not simple, but multicolored as you can see.

The stripe is not simple, but multicolored as you can see.

The song was faint to my ear. I needed to be within a few feet to hear it unaided. A few irregularly spaced ticks (3 or 4 in some individuals, 6 or 7 in others) led into a buzz a few seconds long. Increasingly I am leaning more and more on the SongFinder, but perhaps with that knowledge I will have more success in finding other populations of stripe-faced meadow katydids.

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Wetland Concerns

by Carl Strang

A continuing theme in my regional survey of singing insects is the paucity of wetland species. The only one that is present in good numbers in many wetlands is the black-legged meadow katydid. Other species common in wetlands are habitat generalists such as the Carolina ground cricket and short-winged meadow katydid, which don’t truly count as wetland insects. One clear cause of this problem is the loss of high quality habitat to four invasive plant species (purple loosestrife, reed canary grass, common reed, and cattails). All four are capable of completely taking over a wetland, and examples of this can be found for all four. Small numbers of the singing insects mentioned above can be found in such places, but not the other wetland insect species.

This female long-tailed meadow katydid was a rare wetland species holdout in a small pocket of surviving diverse wetland plants surrounded by cattails, reed canary grass and common reed at Waterfall Glen Forest Preserve in DuPage County, Illinois.

This female long-tailed meadow katydid was a rare wetland species holdout in a small pocket of surviving diverse wetland plants surrounded by cattails, reed canary grass and common reed at Waterfall Glen Forest Preserve in DuPage County, Illinois.

On the other hand, there are some good wetlands out there. Many are small, and this along with their isolation may limit them.

This beautiful little fen at Richard Young Forest Preserve in Kendall County is completely surrounded by woodland.

This beautiful little fen at Richard Young Forest Preserve in Kendall County is completely surrounded by woodland.

Many of the interdune swales at Miller Woods in the Indiana Dunes National Lakeshore have been taken over by the common reed. This one was an exception, but I found only black-legs there.

Many of the interdune swales at Miller Woods in the Indiana Dunes National Lakeshore have been taken over by the common reed. This one was an exception, but I found only black-legs there.

This fen-like wetland at Bluff Creek in Wisconsin’s Kettle Moraine State Forest looks very good. I will want to check it earlier in the season next year.

This fen-like wetland at Bluff Creek in Wisconsin’s Kettle Moraine State Forest looks very good. I will want to check it earlier in the season next year.

Still, I have not given up hope. I found a third good population of mole crickets this year, in a swale at Miller Woods.

Mole cricket tunnels look like miniature mole tunnels. They occur around wetland edges, and occasionally have holes to let out the males’ deep chirping calls, and to provide access for attracted females.

Mole cricket tunnels look like miniature mole tunnels. They occur around wetland edges, and occasionally have holes to let out the males’ deep chirping calls, and to provide access for attracted females.

I also found melodious ground crickets at two new sites in Berrien County, Michigan. Though I did not find dusky-faced or delicate meadow katydids at the Indiana Dunes’ Great Marsh this year, I felt curiously encouraged by this.

Both species were there last year, but with the water level higher in 2013, the vegetation was arranged differently and I did not find them in the same place.

Both species were there last year, but with the water level higher in 2013, the vegetation was arranged differently and I did not find them in the same place.

Maybe the populations of many wetland species took a hit in last year’s drought, and were thinly dispersed in the expanded wet areas of 2013. This is, after all, the first year in which I have surveyed many of these sites. If they need a couple years to recover from the drought, maybe I will find the missing species in the future. Still, how to account for the lack of nimble meadow katydids? This species I have yet to find, anywhere. In the heart of the singing insect season I took my sea kayak into an area where they historically were known.

The channels at the south end of Lake Maxinkuckee in Marshall County, Indiana, have become heavily invaded by purple loosestrife.

The channels at the south end of Lake Maxinkuckee in Marshall County, Indiana, have become heavily invaded by purple loosestrife.

Even the patches of emergent water-dwelling knotweeds, a habitat specifically mentioned in some sources as good for nimble meadow katydids, had none as far as I could tell.

Even the patches of emergent water-dwelling knotweeds, a habitat specifically mentioned in some sources as good for nimble meadow katydids, had none as far as I could tell.

So the bottom line is a disappointing season for wetland species, with a few positive points and hope in the possibility that populations are at a low point from which they will recover.

National Lakeshore Wetlands

by Carl Strang

After catching the melodious ground cricket I drove to Pinhook Bog, a part of the Indiana Dunes National Lakeshore that is open to the public only on rare occasions. I hoped to find stripe-faced meadow katydids, but the bog’s public access boardwalk was bordered by little in the way of grasses and sedges. I was gratified, however, by the presence of sphagnum ground crickets.

These were the first I have found in Indiana. I have seen them only at Volo Bog in Illinois.

After lunch I returned to the place where Gideon, Nathan and I caught the marsh coneheads in early August. Gideon had relayed the news that some of the meadow katydids Nathan also had caught there were dusky-faced, one of the conservative species I had yet to find. The lead paid off.

The legs were totally green, unlike those of the familiar black-legged meadow katydid.

I caught a couple individuals to hold for close-ups.

The head of the dusky-faced meadow katydid is amber colored, with fine dots and lines of red-brown.

While wading the tall grasses and sedges I also spotted a different large meadow katydid with green legs and a beautiful yellow-green face.

Unfortunately I only saw the one, and the auto-focus on the camera frustrated my attempts at a clear photo before she flew away. Though blurred, the image provided enough information for identification.

This was another species on my conservative wetland singing insects want list: the delicate meadow katydid. So, what was so special about this place?

View of the edge of the portion of the Great Marsh under discussion.

For one thing, invasive Phragmites was absent, and cattails were limited to a few scattered plants. Grasses and sedges were the dominant plants. Black-legged meadow katydids were very few, and limited to the dry-soil edges of the wetland. The plants and katydids were zoned. Just inland from the water and mud-flat edge was a zone of shorter, finer grasses in which the only singing insects I saw were abundant slender meadow katydids. Then came taller grasses of intermediate coarseness, where the dusky-faced and delicate meadow katydids were, along with a few marsh coneheads.

Female marsh conehead

The soil became progressively less water saturated as the vegetation rings went outward. Next came a zone of very coarse sedges. The only species I saw in there was, surprisingly, a long-tailed meadow katydid (a tiny species dwarfed by the big triangular sedge stems).  Interspersed here were patches of taller grasses which contained more dusky-faced meadow katydids. This area gave me a strong image of good marsh habitat to carry as I continue to search for these insects in other places.

Chain O’Lakes

by Carl Strang

Last week I spent a day and night at Chain O’Lakes State Park, near the Wisconsin border in Illinois. There are extensive wetlands in that park as well as dry upland areas. Though my singing insect search for the most part turned up common, expected species, I have hope for better results in a future wetter year. In the extensive upland restored prairie areas Allard’s ground crickets were the main daytime singers. In a lower, damper, goldenrod-dominated patch were some black-horned tree crickets (or, possibly, their sibling species the Forbes’s tree cricket).

The heavy but well separated basal spots on the antennae plus the dark antennal color identify this as a black-horned.

In a higher-quality prairie patch not far from some trees I found a bush katydid.

The species cannot be determined from this angle.

A quick capture made for an easy identification.

The brown, curved ovipositor distinguishes the female fork-tailed bush katydid.

Later, after dark, I heard a number of sword-bearing coneheads in the prairie areas.

This species, with its distinctive sewing-machine song, is common in meadows and prairies of the region.

Wetlands are abundant at this park, and some appear to be relatively high in quality.

Pike Marsh

The singing insects were of common species for the most part.

The slender meadow katydid is abundant in wet places.

The most conservative species I found at Chain O’Lakes was a female long-tailed meadow katydid.

This was the first green-legged female of this species I have seen. Usually they are all brown.

I will return to that park in a wetter year.

Seeking Singers

by Carl Strang

The middle of August through September is the peak singing insect season, and on Tuesday I took the first of a scattered series of vacation days to work on a long checklist of targets. I started with searches of the McKee Marsh edge at Blackwell Forest Preserve, and the area around the bridge over the West Branch of the DuPage River at Winfield Mounds Forest Preserve. My main targets were long-tailed and black-sided meadow katydids. I first found those two species in the county last year, and went to these likely locations in hope of finding more. At Blackwell I found mainly black-legged and short-winged meadow katydids, our two most common species in their respective genera. I also saw a few conehead nymphs like this.

Only about an inch long, and lacking wings, these will have to grow fast to complete their development this season. I suspect they are round-tipped coneheads.

After considerable wading through vegetation depressingly dominated by reed canary grass, I finally spotted a female long-tailed meadow katydid. She did not provide a photo op, but I did post some photos last year from another location.

The Winfield Mounds bridge was on the list thanks to my meeting a photographer who had placed a photo of a black-sided meadow katydid on his website. He said he took the picture at the bridge. Again I found a lot of reed canary grass, but dutifully waded in. Again, plenty of black-legs and short-wingeds, but there were scattered others including a female Say’s trig who hopped onto my net.

I didn’t realize how big the females can get, and how they can have long wing extensions reminiscent of a two-spotted tree cricket’s, until I met this individual. She was a good centimeter long.

Shortly after photographing the trig I spotted a black-sided meadow katydid, and so they indeed persist in that area.

Return to the Dolomite Prairie

by Carl Strang

I needed to return to the dolomite prairie at Waterfall Glen as part of my targeted singing insects search. This had been my dragonfly monitoring area until I switched to surveying the nearby Des Plaines River by kayak, and I hadn’t been in the dolomite prairie for two seasons.

This is a unique environment, arguably the rarest in the county, as it is a prairie growing in a thin soil layer that has developed atop a shelf of Silurian dolomite bedrock in the few thousands of years since the last continental glacier melted away. In my dragonfly monitoring there I had seen federally endangered Hines emeralds hunting a few times. This prairie is not established as a Hines breeding area, though they are known to reproduce nearby. As I walked through the drier part of the prairie depicted above, I noticed some meadow katydids, including this female straight-lanced.

My particular interest, though, was a small area of tall sedges and grasses in the wetter east end of the prairie.

This is where I took the photograph of the female katydid nymph I shared a couple posts ago, the brown one that might have been a black-sided, might have been a long-tailed. Almost immediately as I entered the area I began to see a few black-sided meadow katydids, including this female.

But that wasn’t all. In addition to one of the highest densities of black-legged meadow katydids I’ve ever encountered, I also began to see all-brown individuals including this female.

This was almost certainly a long-tailed meadow katydid. According to one paper I’d read, as of 1983 at least there were no known places where black-sided and long-tailed meadow katydids occurred together. I don’t know whether that has changed in the quarter-century since that publication appeared, but if not then this could well be the first documentation of such a co-occurrence. Considering the potential significance of this find, I went ahead and collected one of the all-brown males, while taking close looks at others like this one.

It proved indeed to be a long-tailed meadow katydid. As I sampled the area with my sweep net I also turned up some colorful individuals like this one.

It has a brown body, and in fact except for the green legs is much like the all brown long-taileds. I was tempted to regard these as variants of the short-winged meadow katydid, a much more common species, because some of them had very bright yellow abdomen tips.

In the end, though, I had to conclude that this was a population of long-tailed meadow katydids with both brown-legged and green-legged individuals. Photos supported the structure of the green-legs’ cerci being closer to long-taileds’ than to short-wingeds’, and while in the literature I could find some references to long-taileds with green legs I could find no mention of short-wingeds with brown bodies.

Thus this small area at the east end of the dolomite prairie, which also is the only part of the whole site where I have seen Hines emeralds hunting, proves to have considerable scientific value. Unfortunately it may be on the verge of being lost. It is smaller than it was even two summers ago, as reed canary grass is invading and displacing the tall sedges and native grasses. I don’t know if anything can be done about this. Herbiciding the reed canary grass probably would also do in the native species, and as I understand it there are no other options. I have to hope the Hines’ can hunt elsewhere, and that these meadow katydid populations will be able to hang on in the marginal habitat with which they will be left if the trend continues.

West Chicago Prairie

by Carl Strang

I had high hopes going into West Chicago Prairie Forest Preserve in my search for new singing insects. It is our largest prairie area in the county with a history of minimal disturbance, and has plenty of low, wet areas that would seem good places for meadow katydids. This late in the season, however, much of the ground is dry, and I was finding few species.

It’s always an interesting place, though. The above scene was highlighted by beautiful flowers of smooth blue aster.

The highlight came as I went through one of the persistent wet spots.

Up jumped a brown meadow katydid, and it paused in the open long enough for me to take a couple photos.

It was not a black-sided meadow katydid, as it was a mature male with an all-brown abdomen. According to my references, habitat and color rule out all but the long-tailed meadow katydid. I wanted to catch him to double-check by taking a look at his cerci, but he got away, and despite much searching he was the only one I saw. According to one published study, black-sided and long-tailed meadow katydids have never been found together. This is puzzling, as their habitat needs on the surface are identical. I must check out areas at Waterfall Glen, where I took this photo a few years ago.

This tiny nymph has an ovipositor mid-way in structure between the two species, and as far as I know could have developed into either one.

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