Why the Green Face?

by Carl Strang

This has been a good year for finding additional populations of dusky-faced meadow katydids, a wetland species that has caused me some concern. Once regarded as a ubiquitous marsh insect, they have proven hard to find. In the Chicago region they occur only in remnant marshes and wet prairies with significant amounts of native grasses (though Lisa Rainsong recently reported an Ohio population living in arrowheads), and little or no invasive wetland vegetation. They apparently don’t care for sedges. Such places have become few and far between. So far I have found no evidence of dispersal into restored wetlands.

Dusky-faced meadow katydid, from a newly discovered population at Houghton Lake, a Nature Conservancy site in Marshall County, Indiana.

Dusky-faced meadow katydid, from a newly discovered population at Houghton Lake, a Nature Conservancy site in Marshall County, Indiana.

That said, I have been pleased to find several more populations hanging on in the region. In addition to Houghton Lake, I have found them in two locations in Lake County, Indiana, and have found that they occupy a much larger area at Midewin National Tallgrass Prairie than I realized.

For a time I thought I also had re-found delicate meadow katydids at the Indiana Dunes National Lakeshore. Back in 2012 I got a fuzzy photo of what I thought was that species:

She was gone before I could get anything clearer. The grass-green face seemed to point to delicate meadow katydid.

She was gone before I could get anything clearer. The grass-green face seemed to point to delicate meadow katydid.

When Lisa, Wendy, Wil and I returned to that site in August, we found more green-faced individuals. I also started seeing them elsewhere.

I labeled this photo as a delicate meadow katydid; the green face seemed unambiguous.

I labeled this photo as a delicate meadow katydid; the green face seemed unambiguous.

There were problems, however.

Though some tiny speckles reportedly can occur on the faces of delicate meadow katydids, the green-faced ones often showed the reddish networks typical of dusky-faced.

Though some tiny speckles reportedly can occur on the faces of delicate meadow katydids, the green-faced ones often showed the reddish networks typical of dusky-faced.

This green-faced male has especially heavy reddish markings.

This green-faced male has especially heavy reddish markings.

Also, the ovipositors were too short. They seemed relatively straight, but clearly were less than half the length of the femur.

Also, the ovipositors were too short. They seemed relatively straight, but clearly were less than half the length of the femur.

The songs of some of the males had relatively short intervals of ticks between relatively short buzzes. The ticks all were single, however.

The principal paper published on this species group is by Edward S. Thomas and Richard Alexander (1962. Systematic and behavioral studies on the meadow grasshoppers of the Orchelimum concinnum group (Orthoptera: Tettigoniidae). Occasional Papers of the Museum of Zoology, University of Michigan No. 626:1-31). After studying it closely I have to conclude that all these green-faced individuals are dusky-faced meadow katydids. Thomas and Alexander mention that dusky-faceds can have green faces occasionally (apparently more often around the southern end of Lake Michigan than in the species as a whole). The ovipositor length in females, and the lack of doubled ticks in the males’ songs, seem conclusively to rule out delicate meadow katydids in the individuals I have found. That’s a shame, because it may mean that the species has gone extinct in the region. But I’ll keep looking…

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A Not-So-Silent Grasshopper

by Carl Strang

Until a couple weeks ago, the grasshoppers that drew my interest belonged to two subfamilies, the band-winged grasshoppers and the stridulating slant-faced grasshoppers. The former have displays in which they rattle their wings in flight (crepitation), and the latter produce sounds by scraping their folded wings with their hind legs (stridulation). There is an additional small subfamily known as the silent slant-faced grasshoppers. Structurally they resemble the stridulating ones in having faces that slant back distinctly from the tips of their heads, but they lack the minute pegs needed to produce the stridulating sounds.

I had encountered one of the members of this non-stridulating subfamily, the clipped-wing grasshopper, a few times in Indiana marshes.

Here is a female I photographed a couple years ago in Fulton County, Indiana. The slanting face is clear, as is the distinctive wing-end profile which gives the species its common name.

Here is a female I photographed a couple years ago in Fulton County, Indiana. The slanting face is clear, as is the distinctive wing-end profile which gives the species its common name.

On a recent visit to the Houghton Lake Nature Conservancy site in Marshall County, Indiana, I encountered a cluster of these insects in a little marsh meadow. I started hearing buzzing sounds, and was surprised to find that these were being produced by male clipped-wing grasshoppers.

One of the Houghton Lake males.

One of the Houghton Lake males.

They were behaving just like band-winged grasshoppers. Sometimes they crepitated when flushed, but they also were producing the rattling sounds in undisturbed display flights. They also can fly without crepitating. Their buzzes had the same loud, crackling quality as, say, a seaside grasshopper from the band-winged subfamily.

Looking back at the literature, I see that Richard Alexander included this subfamily in his list of Michigan singing insects, and so this is no new discovery. I wonder if the few species in this subfamily started out as stridulators that also could crepitate, and over time were selected to emphasize the latter display, then having ruled out stridulation lost the ability to perform it.

 

Sights Along the Way

by Carl Strang

It has been a memorable few weeks. This year I took the bulk of my vacation time in the heart of the singing insect season, mid-August to mid-September, and spent most of it traveling around the 22-county area, from southwest Michigan to southeast Wisconsin, where I am seeking the 100 species of cicadas, crickets, katydids and singing grasshoppers that occur (at least potentially) there. This travel took me to many memorable places.

High quality forests are scattered around the region. Sanders Park, Racine County, Wisconsin.

High quality forests are scattered around the region. Sanders Park, Racine County, Wisconsin.

I didn’t spend a lot of time in the forests, however, much as I love them. Most singing insects live in more open habitats.

The dunes around the edge of Lake Michigan provided some of the most open habitats. Warren Dunes State Park, Michigan.

The dunes around the edge of Lake Michigan provided some of the most open habitats. Warren Dunes State Park, Michigan.

One of my favorite areas was Miller Woods at the western end of the Indiana Dunes National Lakeshore.

The trail leads through savanna and past wetlands. Here it crosses a former rail foundation.

The trail leads through savanna and past wetlands. Here it crosses a former rail foundation.

The Miller Woods Trail eventually skirts a large pond at the edge of the dunes, and reaches the beach.

The Miller Woods Trail eventually skirts a large pond at the edge of the dunes, and reaches the beach.

Wetlands included Bluff Creek in the Kettle Moraine State Forest, Walworth County, Wisconsin.

The water was beautiful and clear, flowing over stones and gravel.

The water was beautiful and clear, flowing over stones and gravel.

A fen-like wetland, bordering the creek, contained species such as the fringed gentian.

A fen-like wetland, bordering the creek, contained species such as the fringed gentian.

Sure, I was paying attention to species other than singing insects. At the Houghton Lake Nature Conservancy property in Marshall County, Indiana, I encountered a couple interesting ones.

A Chinese mantis nymph stalked through the wetland vegetation.

A Chinese mantis nymph stalked through the wetland vegetation.

This gray treefrog snoozed in a leaf bed.

This gray treefrog snoozed in a leaf bed.

The most extensive prairie I encountered was in the Bong Recreation Area, Kenosha County, Wisconsin.

Its size alone speaks to the potential in this restoration project.

Its size alone speaks to the potential in this restoration project.

For now I will close with the sunset on my last evening at Bong.

The sunset was a beautiful prelude to a rainy evening in camp.

The sunset was a beautiful prelude to a rainy evening in camp.

The singing insects of course were the focus of all this travel. I’ll share images of some of them in future posts.

Return to Houghton Lake

by Carl Strang

With the singing insect season winding down, I made a final trip of the year to Houghton Lake in north central Indiana. I had not been able to reach certain wetlands on my previous visit, but with much of my strength recovered I was able to wade through the tall dense vegetation.

The periphery of the wetland area was of good quality. There were many interspersed shrubs.

Farther in the center, the portion I explored quaked like a bog, but there was no sphagnum and I imagine it is more calcareous, over marl, and thus more fen-like. The plants were senescing, and I found no singing insects of interest in there, but it will be worth exploring earlier in a wetter year.

One highlight of the trip was a pair of black-horned or Forbes’s tree crickets I found engaged in courtship. My attention was drawn by the unusual buzzing quality of the male’s singing, which he produced whenever the female backed away.

Most of the time I watched them, she was feeding from the glands on his back at the base of his wings.

The male was relatively small and pale. The female was larger, and the darkest individual of this species pair I have seen.

Her head was black, and she had liberal amounts of black pigment on the rest of her body and legs.

These species remain active well into October, and I have wondered if the dark pigmentation is an adaptation for the late season.

Houghton Lake

by Carl Strang

A priority site in this year’s singing insect survey work was Houghton Lake, a Nature Conservancy property near my home town of Culver, Indiana. The muck, marl and sand soils potentially support communities including wetland crickets and katydids that I have not yet found. Last week I spent an afternoon and evening walking through the site.

The property, named for this lake, is of particular interest as it hosts a population of rare massassauga rattlesnakes.

There are many smaller wet areas on the site, which is a flat postglacial lake plain. It has great botanical as well as zoological biodiversity.

For the most part I found a long list of familiar, common species.

Black-legged meadow katydids, like this female, are expected in wet areas.

As I walked the lanes I heard crickets singing in the pattern of Say’s trigs, but with a more mechanical or buzzing sound quality. I spent some time searching, because I thought they would prove to be a species I had not seen before. This effort was rewarded.

The handsome trig is one of the more beautiful singing insects in the region. They are tiny, around a quarter inch long.

Another unfamiliar sound was a rhythmic “warg warg warg” coming from a couple wet prairie areas. The song’s rhythm was like that of slightly musical coneheads, but that katydid produces a call with a distinctly buzzing quality. A comparison of recordings led me to the northern mole cricket. The mole cricket’s song is a chirp, but so deep that it is not readily characterized as such. Like the handsome trig, this was a species new to my experience. For future monitoring purposes I was pleased at how far their songs carry, and that at least sometimes they can be heard singing in the mid-afternoon.

A few conehead nymphs turned up in sweep net samples.

These probably will prove to be round-tipped coneheads, which mature later than most of their relatives.

An additional interesting insect was a great blue skimmer.

This was only the third individual of this species I have encountered.

Most of the conservative species I’d hoped to find at Houghton Lake eluded me, but I was only able to see part of the site, and I intend to return.

Ghost of a Landscape

by Carl Strang

The places we live and work all were wilderness at one time. National parks, state parks, and nature preserves protect and restore areas intended to represent the landscape as it was before large scale agriculture began the sequence of alterations that have brought us to the present day. A number of studies have produced maps showing, in some detail, what the counties of northeast Illinois looked like 200 years ago. In the late 1980’s I decided to do the same for my home area, Union Township in Marshall County, Indiana. Here is a watercolor rendering of my results.

Union Twp painting 2a

I was reminded of that project by Scott’s excellent recent post on Houghton Lake in his blog, Through Handlens and Binoculars. Houghton Lake is the small lake closest to the map’s upper left corner. Recently it was acquired by The Nature Conservancy, and is getting the attention needed to preserve the rare plants and vegetation communities that have persisted there.

My mapping study began with a visit to the County Surveyor’s office in Plymouth, the county seat, to copy the original survey notes. Two different surveyors explored the local wilderness in 1834 and 1836, marking out the land on behalf of the federal government for purchase by American farmers. The 1836 survey covered the Indian reservations east of Lake Maxinkuckee, the township’s largest lake. That land became available to eastern farmers after the forced removal of the Potawatomis via the Trail of Death in 1838.

The surveyors’ main job was to mark the section corners and quarter-section corners (a section is a square mile). They also described the land, so that potential buyers back east could make informed choices. For example, after passing through what is now the center of the town of Culver, on Maxinkuckee’s west shore, surveyor David Hillis wrote, “Land rolling. 3d rate. Hickory etc.” Usually the description was dispassionate, but sometimes a surveyor revealed the sweat and discomfort of the experience. After crossing an extensive marsh at the south end of Maxinkuckee, Jeremiah Smith allowed, “In Sec. 34, at 1.20 (an) inlet 80L. wide coming from S.E. A nasty place.”

One of the surveyor’s helpers blazed and inscribed two “witness trees” at each section corner. The surveyor wrote down the species of tree along with its distance and direction from the corner. The tree species suggests to us what kind of vegetation community occupied that corner, and the tree’s distance from the corner hints at how close together the trees grew in that spot.

The surveyors also were careful to map the edges of lakes and rivers. In Union Township only Lake Maxinkuckee and Lost Lake, off its west edge, still have their 1834 outlines. Houghton Lake, and Moore Lake beside it, today are remnants of the larger water bodies they were in the early 1800’s. Two other lakes in the west-central part of the township no longer exist. They were shallow and easily drained for agricultural purposes before 1900.

Plant communities described by the surveyors as “wet prairies” or “marshes” were extensive mixtures of cattail marshes, sedge meadows and wet to moist prairies. Some of these featured insect-eating plants, the pitcher plants and sundews. See Scott’s post for photographs of some of the botanical beauty preserved around Houghton Lake. I’ll continue this account tomorrow.

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