Cicada Search Concluded

by Carl Strang

A week after my first visit I returned to the forest in Fulton County, Indiana, that had begun to show a significant emergence of periodical cicadas described in the previous post. I found them well into the peak of their appearance. There were more newly emerged cicadas than before, and fresh cicadas and emptied nymphal skins were visible all along the trail in the forest interior.

This time, skins outnumbered new cicadas. The only species present remained Linnaeus’s 17-year cicada, Magicicada septendecim.

The chorus was very loud, and as I drove the nearby roads to determine the extent of this emergence, I found that I could hear it clearly from a quarter mile away and it was audible from half a mile. It extended a mile north of the road where I first encountered the cicadas, and was as much as half a mile wide, but there are clearings within that block so that the forest with cicadas covers an estimated 243 acres or 98 hectares, which my earlier research suggests should be plenty large enough to sustain this population.

Between the two visits, and after the second one, I checked the remaining large forest areas in the 10 counties of northwest Indiana. I found nothing comparable to the Fulton County emergence. There were a few scattered (countable) septendecim in a portion of Potato Creek State Park in St. Joseph County, and the same in a small area of the Kingsbury Fish & Wildlife Area in LaPorte County. Beyond those there were only a few singles, two septendecim in LaPorte County, two Cassin’s 17-year cicadas (M. cassinii) in Porter County, and one cassinii in Lake County.

Considering these observations and historical records, I suspect that the Kankakee River and its broad sandy soil region represents a dividing line between Broods X and XIII in Indiana, at least in the western part. Brood XIII then would extend eastward along the elevated Valparaiso Moraine between the Kankakee River and Lake Michigan. If so, that would place the Fulton and St. Joseph County cicadas in Brood X. The singles in Lake and Porter Counties would be stragglers of Brood XIII. The LaPorte County septendecim may represent vanishing traces of Brood X that once spilled onto the Valparaiso Moraine from the east.

Septendecim Surprise

by Carl Strang

A year ago I was busy in June documenting a 4-year-early emergence of periodical cicadas in a part of northeast Illinois. Periodical cicadas come out in large numbers somewhere in eastern North America each year, and the different areas and years are called “broods,” designated by Roman numerals. The northeast Illinois ones are in Brood XIII and their next main emergence will be in 2024.

This is the year for Brood X, which occupies a large portion of the eastern U.S. According to Gene Kritsky, who has thoroughly researched the history of these insects, Brood X periodical cicadas at one time emerged in every Indiana county. Now they are known mainly in the southern half of that state, but it seemed appropriate for me to check the 10 northwest Indiana counties of my singing insects study region for possible survivors. I didn’t expect to find any, as none have been reported there in recent years.

My own research has shown that forest size matters to these insects, so I used GoogleEarth to pre-select the largest forest blocks to visit in each county. I began in my childhood home county of Marshall and found no cicadas, either in forests on sandy soils or on the glacial moraine east of Lake Maxinkuckee.

I proceeded to Fulton County, just south of Marshall. I stopped beside County Road 450N east of US31, turned off the car motor, and listened. Could it be? Yes, I was hearing a chorus of “pharaoh,” the calling song of Linnaeus’s 17-year cicadas, Magicicada septendecim. I made a recording and continued down the road. I was gratified to find an entrance to Richland Restoration Park, which had trails into the forest. Newly emerged cicadas were resting on vegetation beside the trail.

The orange line between eye and wing separates septendecim from the other 17-year cicada species.

Shrubs with the cicadas were frequent along the trail.

Though one little area of 3-4 square meters had 25 cicadas, much of the way along the trail had none.

My overall impression was that these cicadas still were short of their peak, and I intend to return. I want to get some idea of how big this population is, how extensively it covers its forest, and whether any of the other 17-year cicada species also will emerge. Without the frequently more numerous Cassin’s 17-year cicadas (M. cassinii) to buffer them from predators, can the septendecim persist? In any case, I was pleased to find that at least one genuine Brood X remnant hangs on in my region. I still have a few more counties to search.

As the county road designation indicates, the park is 4.5 miles north of Rochester. It is closed on Wednesdays and the second Saturday of each month. The cicadas will be done before the end of June.

Tying a Knot on 2020

by Carl Strang

I know of no one who is sad about putting the year 2020 in the rear-view mirror. I have posted my research highlights for the year already, but find some miscellaneous photos remain that will fill out the story. As I detailed in earlier posts, ditch hopping was an important activity through the summer.

Another view of a drainage ditch in Kankakee County

I paid a couple visits to the Chicago Park District’s Big Marsh for the first time this year. Of greater interest to me than the wetlands was an area of sparse vegetation in the eastern part of the park.

When I run across scenes like this I automatically want to check for unusual grasshopper species.

Indeed, I found my third population of pasture grasshoppers (Orphulella speciosa) for the region here, and a second population of Kiowa rangeland grasshoppers (Trachyrhachys kiowa) for Cook County.

A pasture grasshopper at Big Marsh Park
One of the Big Marsh Kiowas

There also was a strikingly marked nymph.

The white spots stand out. I don’t have a species ID.

I made a day trip to the Nachusa Grasslands, west of my study region. The area has a nice variety of singing insects.

One of the few Texas bush katydids (Scudderia texensis) I encountered in 2020. This Nachusa female provided a nice photo of her sharply bending ovipositor.

In my home county of DuPage, West Chicago Prairie Forest Preserve provided some highlights.

The prairie cicada (Okanagana balli) population at West Chicago Prairie continues to respond to the Forest Preserve District’s restoration efforts.
These small cicadas are active for only a brief time in the early summer.

Later in the season I made a slogging trudge to a remote corner of West Chicago Prairie, hoping to find rare wetland katydids.

There were no new species, but a separate location for long-tailed meadow katydids (Conocephalus attenuatus), including this male, within the preserve.
This West Chicago Prairie female’s ovipositor, fading out of focus in the dim light that day, illustrates how the species gets its common name.

Finally, I continued both monitoring and restoration efforts at St. James Farm Forest Preserve.

Typocerus velutinus is one of the more common longhorn beetles in DuPage County.
While gathering Joe-Pye weed seeds to spread in our cleared area, I found this mating pair of walking sticks (Diapheromera femorata).

Clearly 2020 had much to offer, after all, and I hope for plenty of new encounters in 2021. Happy New Year to you.

Ditch Hopping: Woodland Meadow Katydids

by Carl Strang

As I started seeking northern mole crickets in rural ditches at night, I realized that ditches and streams are oases of habitat winding through the biodiversity wastelands of corn and soybeans in large portions of the Chicago region. I started checking ditches during the daytime. The biggest hit came early on, when I discovered woodland meadow katydids beside a ditch in southeastern Kendall County, Illinois. I had dismissed expectations in that county for the species, so this was a big surprise.

Woodland meadow katydid (Conocephalus nemoralis)

The ditch seemed an unlikely location for that katydid, which I had found previously only at woodland edges. A single small tree was the only nearby woody plant.

One of the Kendall County locations for woodland meadow katydids

This proved to be a common pattern, however. As I added county after county to the list of those where I have found woodland meadow katydids, sometimes there were woodland edges adjacent to the ditches but sometimes there was little woody vegetation to be found.

Updated site map for woodland meadow katydids

I was frustrated in LaPorte County, Indiana, and Berrien County, Michigan. I later learned that woodland meadow katydids also can inhabit dune edge habitats along Lake Michigan, so I will seek them there in 2021.

Ditch Hopping: Northern Mole Crickets

by Carl Strang

Last year, while driving a rural road at dusk in Newton County, Indiana, I stopped beside a drainage ditch to listen for slightly musical coneheads. Instead I heard a northern mole cricket, and I realized that I needed to turn off the car engine to hear the low-pitched song.

Northern mole cricket specimen (Neocurtilla hexadactyla). This face-on view shows the modified front legs that make this cricket such a good digger.
Recording of northern mole cricket calling song

This turned out to be a lucky observation, as it opened a way for me to conduct my research profitably in this covid19 year. I spent most of the peak singing insect season ditch hopping. I used GoogleEarth and DeLorme map books to identify likely spots where rural roads intersect drainage ditches and streams. Such stops kept me away from concentrations of people.

Typical drainage ditch, Kankakee County

This method gave me a cluster of mole cricket locations on ditches and streams in northeastern Kankakee County, Illinois, all tributaries of the Kankakee River. I also added county records in Pulaski and Fulton Counties, Indiana. Otherwise, the many evenings of searching mainly told me where mole crickets are not, and I have concluded that I will add no more counties in Illinois or Wisconsin.

Map of the Chicago region showing where I have found northern mole crickets (black dots) and identifying counties where there are old records for the species (white dots).

I have satisfied myself that I am not going to find them in Cook County, Illinois, but there still are a few places to check next year in St. Joseph County, Indiana, and Berrien County, Michigan.

Japanese Burrowing Crickets Spreading Rapidly

by Carl Strang

The Japanese burrowing cricket is, as the name suggests, an oriental species that was accidentally introduced to this country at one or more coastal ports. They have spread out from there, and I first encountered them in the Chicago region at Bendix Woods, a St. Joseph County park, in 2014.

Japanese burrowing cricket, Velarifictorus micado

Since then I have found them increasingly at sites throughout the southern portion of the Chicago region.

Counties of the Chicago region, with years when I first observed Japanese burrowing crickets in each.

Fulton County, at the southeast corner of the region, is the most remote from my home, so I don’t go there often. I rather imagine that Japanese burrowing crickets are in the city of Rochester, at least.

Note that I added 7 counties this year. This is in part because they are increasing in the region, and in part because I encountered them frequently while ditch hopping (more on that in later posts). Rural drainage ditches may be major dispersal corridors, along with human-assisted transport in landscape and building materials. The crickets also may fly to expand their range, but this possibility remains speculative.

Japanese burrowing crickets have been ubiquitous and abundant in Indianapolis for years. Last year I found them to be common in Rensselaer, Indiana, one of the southernmost cities of the Chicago region. There is every reason to believe that they will become abundant through most or all of the region over the next decade. They thrive in loose landscaping stone and in lawns, which are not prime habitat for our other members of the field cricket group, so it is possible there will be little effect on our native species.

Here is the most common calling song of the Japanese burrowing cricket:

Perhaps less commonly heard is this alternative:

A New North for Jumping Bush Crickets

by Carl Strang

We are getting into the latter part of the singing insects season, and I have some catching up to do here. This time, just a quick note to update the northward advance of jumping bush crickets. This species has been spreading more rapidly than any others of our native singing insects. The Fox River has been my focus in recent years, as it appears to be a corridor they are following. The next county I expected them to reach was McHenry, and this year for the first time I found a population in the city of Algonquin in southern McHenry County.

Jumping bush cricket

I first heard jumping bush crickets in southern Kane County (immediately south of McHenry) in 2012. They have covered the 30-mile length of that county in 8 years. If they continue at that rate, they will reach the Wisconsin border in 6 years or so.

The red dot indicates the new location in McHenry County.

Their songs remind me of little bells tuned to slightly different pitches, and are loud and easy to hear as the males sing from hidden perches in trees, vines and shrubs. Here is a recording featuring jumping bush crickets:

Editorial: Are There Any Good Cops?

by Carl Strang

This is a nature blog, but from time to time I have felt the need to insert an editorial. This is one of those times. I am an ecologist, trained and practiced in seeing connections among things. The city of Kenosha, Wisconsin, is in my study region and I have picked up singing insect county records in its parks. It saddens me to think that Kenosha may come to be thought of with the same negative connotations that saddled Selma and Montgomery, Alabama, in my youth.

The title of this post is deliberately provocative. Frequently I have seen the opinion expressed that bad cops who shoot to kill innocent civilians simply because they are black are a minority, that most cops are good cops. But I feel that at this point in our history we need a redefinition of what constitutes a good cop. Is it enough to be a police officer who does not grab any opportunity to kill a black man? Consider what happens in the wake of the headlines. Police unions close ranks in support of the officers who commit these killings. Seeing this, attorneys general do not press charges. We hear nothing from the supposed “good cops.”

Police officers are human beings. It needs to be acknowledged by all that this means some of them are mean spirited, that some are the manipulative sort who will call upon their “brothers” to support their evil actions. This needs to change. There needs to be a transformation of cop culture so that the ranks recognize and fail to support those few who use the power of their position to do evil. There need to be conversations in police stations, leadership by chiefs, making clear that those who try to use the power of their badge to do wrong will be outcast. Chiefs and veteran officers need to make clear to attorneys general that they need to do their jobs, and the good cops will support them.

It is fair to ask how I, an old white guy, have acted with respect to this issue. From the early times when wrongful killings of black men and women by white cops came into the news, I have imagined myself in the position of a black man and realized how this can make them fearful. I have felt profound respect for the patriotism and restraint of African American culture, given the history of slavery, lynchings, segregation and racism. My response has been on the personal level, smiling, waving, and greeting those I meet with a special emphasis on those of other races. I recognize that I am a symbol, and I try to create a positive, supportive moment of encounter to counterbalance the frowns and rejections.

It extends beyond race. I am a runner, and I love the girl runners. I love the way women have embraced my sport, and I am happy when I encounter a woman on the trails. As always, I wave and smile. Often the greeting is pointedly ignored. I understand this and admire the courage of a woman who goes out alone for a run, knowing how women runners have been sexually assaulted and killed by evil men. I recognize the fear and am saddened by it.

I suppose my behavior could be labeled racist or sexist. Yes, I recognize the race, gender, and age of every person I meet. Over the years I have learned through experience that differences of gender and race have little meaning for me, however. Each individual is worthy, and differences of race, gender, sexuality and so forth are insignificant compared to the uniqueness of each person. It is our behavior and regard of one another, not abstractions or stereotypes of race, gender, etc., that matter.

What about demonstrations? The motivation to express opposition to these wrongful killings is understandable, but they have a counterproductive component. Some express their outrage through violence. Even if only a few behave in this way, it supports the notion that the demonstrations are against the police as a whole, setting up an us-versus-them framework so that police sometimes respond in force, feeling unified in supporting one another and justified in using violence even against the peaceful protesters.

The opponent here is not the police, but something more abstract: a cultural tradition of tribal identity, loyalty and brotherhood. Those are strong bonds, but they must be made apparent as weaknesses being exploited by wrongdoers. They must be revealed as secondary to the reason we have police in the first place: to serve and protect. Serve. Protect. Serve and protect the public first, and fellow police officers second when the two come into conflict.

Flagging in the Heat

by Carl Strang

On Saturday I completed my survey of 2020 periodical cicada reproduction in the Chicago suburbs. I focused on 18 suburban cities where I had observed wave chorusing, mapping out walking routes where I counted the flags that indicate where female cicadas deposited eggs in tree and shrub twigs. Altogether I walked 33.4 miles on hot afternoons, but the main physical challenge was the stiff neck I developed from constantly looking up into the trees. I will need to consult with periodical cicada specialists to be sure, but it seems to me that the numbers support a persistent, parallel splinter regional population that will continue to appear 4 years ahead of each major emergence.

Here I will share two sets of data. First, the highest numbers of flags in single trees.

Map of Chicago suburbs I surveyed for periodical cicada reproduction. Numbers indicate the highest count of flags in a single tree. Flags are withered twig ends that result from female cicadas inserting their eggs and cutting off the twig’s vascular system.

The high count of 33 was in Brookfield. I was walking residential streets, so my counts are transects rather than area surveys. The next map gives average numbers of flags per 100 meters. I used that number as the divisor because I often observed 1-2 wave choruses per block while driving earlier in the season, and 100m represents a middle-of-the-road block length.

Average counts of flags per 100m in Chicago suburb survey routes.

The highest counts of 10.5 and 9.1 are in LaGrange and Western Springs, respectively. These counts are conservative: I usually could not see all sides of a tree, canopies blocked part of the view, and to an unknown but certain degree flags had fallen to the ground and were removed by homeowners (this takes away some eggs, but there are others in the twig above the break).

Flags fallen to the ground at Madison Meadow Park, Lombard. In a residential yard these likely would have been removed before I could count them.

This fallen flag carried some eggs, leaving others still on the tree. Sugar maples were a popular choice by female periodical cicadas.

In addition to these transects in the cities, there were isolated parks and sites worth considering. At Pioneer Park Forest Preserve in Naperville, a single isolated non-wave chorus tree produced 7 flags spread between two trees. A similar case at Cook County’s Bemis Woods produced 18 flags. A park in Downers Grove had 37 flags. Other forest preserves had enough flags to suggest that their local off-year populations will continue: 22 at Lyman Woods, 13 at Greene Valley, and though I was disappointed by the size and timespan of the wave chorus at Wood Dale Grove, there were well over 30 flags there.

Tree with flags at Pioneer Park

First Flags Over Brookfield

by Carl Strang

Cicada specialist John Cooley taught me a new term: flagging. This refers to dead and broken twig ends on trees and shrubs where periodical cicadas have placed their eggs. Mama cicada slits the underside of the twig in several places and injects her eggs. This impedes water flow, and with circulation cut off the leaves turn brown. The cuts weaken the twig, and it may break partly and bend down, producing a “flag.”

Now that the periodical cicadas are done singing in many places and nearly so in others, it is time to start looking for these flags. They will provide the best measure of how this off-year emergence may continue for another generation. On Tuesday I started in Brookfield, the first place where I heard a full wave chorus of singing males.

I soon found a tree with many flags.

This tree was in the same place where I found that initial wave chorus.

The brown, drooping flags stand out against the green foliage. This prunes the tree a bit but will not cause significant harm. I saw many trees with one or two flags, but only the two in the photos had many. I expect to see more of them the next time I check.

John said that dry weather and thunderstorms enhance flag formation. A lack of water flow enhances the twig-end drying, and the buffeting winds of storms partially snap the weakened twigs. I heard no singing cicadas in Brookfield, and so this is the very beginning of this process. On the way home I swung through northern Hinsdale, another area that had abundant wave chorusing at the peak. There still were many small non-wave choruses, so it was not surprising that I saw only a couple flags during the drive-through. I am hopeful that flagging will develop over a period of weeks, allowing me the time needed to get a good assessment of periodical cicada reproductive success across the Chicago area this year.

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