Landscape Ecology of Singing Insects 2: Human Influences

by Carl Strang

The previous post illustrated that the Chicago region has been a dynamically changing landscape through the recent millennia, but that now is overshadowed by the alterations our own species has made. Burgeoning human numbers have overwhelmed the planet’s ecosystems, and the native habitats described earlier mostly have been replaced by agriculture and urban growth in the Chicago region. One of the more dramatic changes is the loss of the Kankakee wetland, once described as the Everglades of the North. That vast wetland was drained for agriculture, and only a few pockets of it survive in preserves. Much of the Kankakee River in Indiana is now a straight channel with constructed high levee banks. Other smaller wetlands received similar treatment, with drainage ditches spreading across the agricultural portion of the region. This is not universally devastating to wetland species. Northern mole crickets, for instance, occasionally can be found along drainage ditches.

Drainage ditch, upper reaches of the Kankakee River, St. Joseph County, Indiana. Note farm fields on both sides.

Prairie mostly has been replaced by agricultural fields, and fire suppression has led to its invasion by woody plants. Specialists such as the prairie meadow katydid, prairie cicada and short-winged toothpick grasshopper are hard to find.

Prairie meadow katydid

My singing insects research has required a lot of driving to reach the relatively tiny surviving preserves and parks to which many of the species are now restricted. Much management effort is required in these little islands to maintain their habitats. There are exceptions, of course. Many other species have thrived under our influence. These are mainly weedy ones such as the striped ground cricket, short-winged meadow katydid and Carolina grasshopper, which do well in disturbed habitats, along with woodland edge species such as the greater angle-wing, snowy tree cricket, and jumping bush cricket, which can meet their needs in residential neighborhoods dominated by lawns and scattered trees and shrubs.

Jumping bush cricket

Habitat destruction is not the only human influence. Climate change is the probable cause of northward range expansions by several singing insect species, and it likely will lead to the extinction of the sphagnum ground cricket from the region as the sphagnum bogs dry up. Say’s cicada and some northern grasshoppers already appear to be pushed out.

Sphagnum ground cricket

Climate change isn’t simply a matter of rising temperatures, as the term “global warming” may seem to imply. Global warming is an accurate enough term, as the simplest way to measure climate change is to track the global average temperature. But the point is that our changes to the Earth’s thin skin of atmosphere are increasing its held solar energy. That energy alters patterns of atmospheric flow and the behavior of storms. Droughts, more frequent flood-causing rains, and seasonal increases or decreases in temperature that seem abnormal are examples of results we observe locally. The singing insects are forced to adjust as best they can. Droughts force sphagnum ground crickets into the wettest parts of their bogs. The severe drought of 2012 concentrated wetland meadow katydids and marsh coneheads into the small portions of the Great Marsh in the Indiana Dunes National Park that remained wet. Oblong-winged meadow katydids may be pre-adapted to such year-to-year variability. Blatchley (1920) observed that their eggs, laid in moist soil, can take 2-3 years to hatch. In my travels through the region I failed to hear a single individual in the years 2010 and 2019, but in other years they have been abundant and widespread. Some of the cicadas and other species may have similar flexibilities.

Oblong-winged katydid

People also have introduced plant species from other parts of the world which, released from the consumers and competitors which hold them in check in their native lands, have become invasive plants here. Their unfair competitive advantage has led to their displacing the region’s native vegetation in an increasing number of places. This is most evident in our wetlands. Wetland meadow katydids and other singing insects are limited to places where native wetland grasses have not been supplanted by reed canary grass, common reed, purple loosestrife, and hybrid cattails. These invasive plants are proving difficult to control, and the outlook is not good for species such as the dusky-faced meadow katydid and marsh conehead. To my knowledge the once relatively widespread stripe-faced meadow katydid now is confined to a single site, and the slender conehead, never known from many locations, apparently is gone from the region.

Stripe-faced meadow katydid

Introductions have not been limited to plants. Several species of singing insects also have been imported. Roesel’s katydid is the most common of these in our region. A European predaceous katydid, Roesel’s was introduced to the Montreal, Quebec, area several decades ago and expanded from there. They occur in open habitats with tall herbaceous vegetation throughout the Chicago region. Japanese burrowing crickets are thought to have arrived at the port of Mobile and spread out from there. They are abundant as far north as Indianapolis, and common in Rensselaer in the southern part of our region. With scattered new appearances each year occurring as far north as DuPage County in Illinois, so far, I expect them to become widespread and abundant here. The tropical house cricket represents the possibility of other, short-term introductions that are unlikely to persist in our climate.

Roesel’s katydid

Berrien Explorations

by Carl Strang

The end of August found me in Berrien County, Michigan. The first stop was the Butternut Creek Fen preserve, where I met tree cricket specialist Nancy Collins. We spent an afternoon and evening seeking tamarack tree crickets, which had been found there years ago. There are abundant tamarack trees, but we were puzzled by the crickets’ no-show. None sang, and hours of arm-tiring sweeping of foliage with long-handled nets, as well as visual scanning of branches, were fruitless. We found other species, though, and provided the site owners with a list of what we observed.

When Nancy found this fork-tailed bush katydid I was hopeful that it would prove to be a rarer cousin, the treetop bush katydid, but no dice.

Oblong-winged katydids also are at the site. My new white chamber setup worked well in the back of the car.

The next day I wandered in Berrien, St. Joseph and LaPorte Counties. The best find was a new site for me, Glassman Park in Berrien County. I bypassed some nice-looking forest, then was captured by a mundane looking grassy area adjacent to the I-94 right-of-way. It proved to have some interesting grasshoppers.

Most of these proved to be pasture grasshoppers, only the second population of this locally distributed species I have found in my study region.

A second species had a much different look.

The handsome grasshopper has an even more slant-faced profile.

With a color pattern like this, the handsome grasshopper is well named.

The day was my final in Berrien County for 2018, but there is more singing insect work to be done there in coming years. That is bound to include at least one more listening stop at Butternut Creek.

 

Recent Photos

by Carl Strang

Time to bring out a backlog of photos from the first half of August. First, a couple bumble bees from my last day on the job at Mayslake Forest Preserve.

This Bombus auricomus was huge, practically dwarfing the carpenter bees working nearby. She must have been a new queen, stocking up for her long winter wait.

This Bombus auricomus was huge, practically dwarfing the carpenter bees working nearby. She must have been a new queen, stocking up for her long winter wait.

Nearby, this yellow bumble bee Bombus fervidus also worked the wild bergamot.

Nearby, this yellow bumble bee Bombus fervidus also worked the wild bergamot.

The remaining photos are from a few days’ bouncing around in singing insect surveys.

This oblong-winged katydid peeked out through a hole in the vegetation in the late dusk at Midewin National Tallgrass Prairie.

This oblong-winged katydid peeked out through a hole in the vegetation in the late dusk at Midewin National Tallgrass Prairie.

This mottled sand grasshopper at Kankakee Sands was my first for Newton County, Indiana.

This mottled sand grasshopper at Kankakee Sands was my first for Newton County, Indiana.

Female Carolina ground crickets are distinctive with their short ovipositors. This one posed at Subat Forest Preserve, Kendall County.

Female Carolina ground crickets are distinctive with their short ovipositors. This one posed at Subat Forest Preserve, Kendall County.

Sound Ideas: Katydids that “Katydid”

by Carl Strang

The name “katydid” has come to cover a wide range of singing insects, most of whose songs do not sound anything like that name would suggest. Today I wish to share recordings of two species which seem to say something like that name. Both are common in the region. First up is the oblong-winged katydid:

Oblong-winged katydid

Oblong-winged katydid

The next recording is of a common true katydid. Though this individual has only two syllables per song, some have three to match the syllables in “katydid,” and others have 4 (“katy didn’t”) or more.

Common true katydid

Common true katydid

Ah, summer.

 

Bendix Woods Bioblitz

by Carl Strang

It’s been an unusually busy September, and there has been no time for writing in recent days. Much of that time has been occupied by field work, however, so I have a backlog of observations to share through a number of posts. Last weekend there was a bioblitz at Bendix Woods, a St. Joseph County Park in Indiana. Many of the scientists who participated in this species count could do it as a day trip. A few of us camped overnight. It was well worth it, and three posts will be needed to tell the full story.

I was there for singing insects, of course, and so needed to do survey work after dark as well as during the day. The nighttime drive along the park’s roads revealed a healthy population of oblong-winged katydids.

This one took a break from singing to seek out a new perch, his long legs moving slowly in the cooling night air.

This one took a break from singing to seek out a new perch, his long legs moving slowly in the cooling night air.

While trying to locate the katydid I ran across a couple other members of the Bendix fauna.

Gray treefrogs are abundant at Bendix Woods. I saw at least 8 individuals during the 24-hour event.

Gray treefrogs are abundant at Bendix Woods. I saw at least 8 individuals during the 24-hour event.

This female walking stick, Diapheromera femorata, was nearly 4 inches long.

This female walking stick, Diapheromera femorata, was nearly 4 inches long.

Lights set up by a Field Museum of Natural History team drew in a variety of moths, caddis flies and others.

This was a crane fly that got hung up on a support rope, not a hangingfly, as some of us hoped at first glance. The hangingflies are a group of scorpion flies.

This was a crane fly that got hung up on a support rope, not a hangingfly, as some of us hoped at first glance. The hangingflies are a group of scorpion flies.

 

This pine tree spur-throated grasshopper came to the light, and I saved it to photograph the next day. The species proved to be common in the groves of white pines which have been planted in the park to spell out “STUDEBAKER” in very large block letters that can be read only from the sky.

This pine tree spur-throated grasshopper came to the light, and I saved it to photograph the next day. The species proved to be common in the groves of white pines which have been planted in the park to spell out “STUDEBAKER” in very large block letters that can be read only from the sky.

 

I’ll close out with another, more widespread species, the differential grasshopper.

I’ll close out with another, more widespread species, the differential grasshopper.

There were two singing insect species that I met for the first time at Bendix Woods, and each will get a post of its own.

Encounters Along the Way

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.

Female Oblong-winged Katydid

by Carl Strang

On Saturday morning I was riding my bike on the Prairie Path when I passed a katydid on the trail. I turned around, dug out the phone, and
took some photos. It proved to be an oblong-winged katydid.

The tip of the right forewing is damaged.

Not certain of the phone-camera’s capabilities, I took photos from both sides. I didn’t expect much from the backlit side, but later learned something from it.

With the sun shining through the wings, you can see not only that this is a female, but get an idea of the ovipositor’s shape.

It was palpating the trail surface, apparently picking up some minerals.

Insects at the Campground

by Carl Strang

The overnight campout at Waterfall Glen Forest Preserve that concludes the Roger Raccoon Club provides opportunities to observe various aspects of natural history. Last week the campground’s gravel parking lot, damp from overnight rain, apparently held a good supply of dissolved minerals, as it attracted butterflies representing at least 5 species.

Most remarkable was this giant swallowtail, a species uncommon in DuPage County but encountered regularly in small numbers at Waterfall Glen. I believe their main food plant in northeast Illinois is prickly ash, an infrequent shrub.

After dark an orchestra of singing insects filled the forest with sound. Dominant that night were large numbers of common true katydids, with smaller numbers of scattered two-spotted tree crickets, rattler round-winged katydids, and oblong-winged katydids. I needed a photo of the last species, and was able to find one singing close to the edge of the woods.

This oblong-winged katydid is holding his wings apart in singing position. Rasp and file structures on the brown portions of the two wings are rubbed together to produce the song.

As it happened, some of the kids found another male on their tent in the morning. I gave them a brief lesson about it, and took another set of photos.

Here the wings are in their normal folded position.

Some of those singing insects represented my first observations of their species this year.

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