Even More Melodious

by Carl Strang

Relatively little has been published about melodious ground crickets (Eunemobius melodius). These tiny insects with their beautiful trilling songs first revealed themselves to me at Indiana Dunes State Park in 2012.

Melodious ground cricket

They were abundant in an open, low wet forest associated with the shrub swamp that occupies a central position within that park. The ground there has relatively little vegetation beneath the trees, with abundant rotting logs on the ground, mosses, ferns, and some other vascular plants, but much ground with nothing but wet leaf litter. On another day, I heard a few melodious ground crickets in a similar habitat at Warren Woods in Berrien County, Michigan, and in a shrub swamp in Warren Dunes State Park, also in Berrien. There the matter rested until I heard a single individual in a bottomland forest in Tippecanoe River State Park, Pulaski County, Indiana, late last year. That observation planted an idea: perhaps this species is more abundant than I realized. Flood plain forests, resembling that original site at Indiana Dunes State Park, can be found along all the major rivers in the Chicago Region. Could melodious ground crickets be found in all those places? That set the stage for one of this year’s goals.

I first tested the idea on August 11 at the Momence Wetlands, a state-owned property in Kankakee County, Illinois. As I walked into this Kankakee River floodplain forest, I was struck by its similarity to other places where I have found melodious ground crickets, and before long I began to hear them singing. As I have come to expect, they were on the ground, in or close to rotting logs. I made sound recordings to analyze for confirmation, but the contrast between their songs and those of Say’s trigs (Anaxipha exigua), which were singing nearby up in tall herbaceous vegetation, made the identification clear in my mind before the analysis later confirmed it. According to the comprehensive database used to build the species’ maps for the Singing Insects of North America website, this was the first time the melodious ground cricket was documented in Illinois.

That same day I found them on both sides of that same river in Indiana, adding Lake and Newton County records. With that success in hand, I put some time into searching for melodious ground crickets in other counties and river systems. So far, I have found them along the Kankakee River in Starke and LaPorte Counties, and the Tippecanoe River in Fulton and Marshall Counties, all in Indiana. The significance of this is that the Kankakee River flows west to co-form the Illinois River and flow into the Mississippi. The Tippecanoe joins the Wabash River, flowing south to the Ohio River. Though the Yellow River (a tributary of the Kankakee) and Tippecanoe both cross through Marshall County, their watersheds are well separated by miles of dry moraines and sandy areas. The crickets were absent from bottomland areas that recently had flooded, but rotting logs in slightly more elevated portions consistently held singing crickets.

In Illinois, I found melodious ground crickets in Will County around the confluence of the Kankakee and Des Plaines Rivers, and upstream from there along the Des Plaines in my home county of DuPage. That is as far as I will go with this pursuit as the season winds down, but I expect to add more counties to the list next year. I conclude that at least in this limited but widespread habitat type, the melodious ground cricket can be sought throughout the southern portion of the Chicago region. Here is the map to date:

Map showing counties where I have found melodious ground crickets in the Chicago region, updated with 2017 observations.

I close this post with a couple sound recordings, both made at the Des Plaines Riverway Forest Preserve in DuPage County, Illinois, on September 6. The first, of a melodious ground cricket:

The second recording is the song of a Say’s trig:

Ground crickets, as the name suggests, sing from the ground (or, in the melodious ground cricket, sometimes from within a rotting log). Trigs sing from perches up in the vegetation. In this pair of recordings, the statistics quantify the differences you should be able to hear. The melodious ground cricket had a lower-pitched song, at 5.11 kHz, and a slower pulse rate, at 22/second. The Say’s trig’s corresponding numbers are 6.10 kHz and 31/second. The temperatures near the two singers bring out the contrast even more, the elevated trig at 17.7C and the ground cricket at 19C (i.e., if the trig had been singing at the ground cricket’s temperature, one would expect the dominant frequency and the pulse rate both to be even higher). The two species, as I mentioned above, often occur close to one another, making this difference worth noting.

 

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Dragonfly Monitoring Run

by Carl Strang

On the 4th of July I made my first dragonfly monitoring run of the year, on my assigned stretch of the Des Plaines River at Waterfall Glen Forest Preserve. With a total of 378 individual dragonflies and damselflies tallied, it was far higher than any other count since I took this route beginning in2009. Of course, there was a lot more to enjoy than just Odonata.

A string of great blue heron nests between the boat launch and the start of my route still had some youngsters approaching fledging. Their loud rhythmic guttural calls signaled the arrival of a parent, back from fishing the river.

The carp fence I saw under construction when I last paddled the Des Plaines in the fall is complete. Am I being ignorant or properly skeptical in doubting this will achieve the desired result of keeping Asian carp from moving between waterways?

My thinking, for what it’s worth, is that even if the mesh is fine enough to block tiny youngsters that might slip through at flood stage, there will be breaches from floating logs.

Later, when my run was nearly complete, I encountered this northern water snake.

I was surprised that it seemed undisturbed by my close approach. Then I saw that the eyes were obscured. The snake either was on the verge of shedding, or the scales over the eyes remained stuck when the rest of the skin came off during the last shed.

Entertaining as these sideshows were, dragonflies and damselflies were the main event. Jade clubtails were the most abundant of the 5 species of dragonflies that day; I counted 46 altogether.

Jade clubtails mainly are to be seen perched on objects like this stump.

Common whitetails also were regular sights, some laying eggs.

Here a male common whitetail shares a stump with a bluet and a clubtail.

Most of the individuals were damselflies, however, in 8 species. The largest were a few American rubyspots.

This one was so steadfast that I was able to bring the camera to within a few inches of it.

The largest count of any species was 108 blue-tipped dancers. I didn’t get a photo of any of them, but one of the 82 powdered dancers, a close relative, posed on my deck line.

Such accommodating individuals make identification easy.

The most abundant bluets this time were stream bluets.

The stream bluet is one of the black-type bluets, having a mainly black abdomen.

Stream bluets and hordes of dancers were laying eggs in floating vegetation mats.

The several tandem pairs, perched on the vegetation and laying, may not be as visible here as the unattached and hopeful males hovering above.

I had thought I might do a little fishing on the way back, but the time and mental effort required to identify and count so many insects left me glad simply to paddle back up to the put-in.

Great Blue Heron Dossier

by Carl Strang

It has been a while since I posted one of my species dossiers. The idea is to make a record of what I know of a species from my own experience rather than what I have learned from others. This is a valuable exercise. When I got the idea and started it, I was embarrassed by how little I could write even for common species. It has forced me to pay more attention, to observe more, to be more discriminating in what I can claim to know about natural history. Even books and, yes, Internet sources like this blog need to be read skeptically. Today I choose the great blue heron, a species that played an important role in inspiring my interest in natural history studies. Records are dated with my code that begins with the day of the month, followed by a two-letter month code (usually the first two letters of the month’s name) and a two-numeral year. The code 16JE99 would indicate June 16, 1999.

Great Blue Heron

First observed at Hawk Lake, where several fished along the east side each evening in summer during my childhood. These were an early inspiration for my bird watching interest. Also observed in PA, along the Tippecanoe River in IN, in DuPage County, in Florida. Seek food usually in relatively deep water, sit-and-wait foraging. They quickly extend the neck to seize or spear fish or other prey. On rare occasions I have seen them briefly swimming on the surface of water too deep to wade. One in FL waited for fishermen to catch fish, then ran up in hope of getting the catch.

They have loud raucous squawking calls, a brief one in flight (often when disturbed) and a longer more rattling one when handled (i.e. at Willowbrook’s wildlife hospital).

Rookery established around 1967 south of Culver, Indiana, near the Tippecanoe River, in several large sycamores at the edge of a small woodlot near S.R. 17. That site still was used through 1986. Birds appear standing in nests in mid-March, radiate out in many directions to feed. Great blue herons then also reached all parts of DuPage County, IL, despite no rookeries there (a large rookery south of the county at Plainfield).

24JA89. A great blue heron flying east of Lake Maxinkuckee, IN.

10MR00. Several herons have returned to the new, small (10-nest) colony at Danada Forest Preserve.

7MY00. Great blue herons croaking in flight, traveling above West DuPage Woods Forest Preserve. An extended string of them, so the calls may be communication between flying birds.

13NO01. I count 25 nests, now, in the Danada rookery. The trees are at the edge of a pond. They are not sycamores, but I didn’t get close enough to ID. Elm shape.

21FE02. A single heron was standing on a nest in the Danada rookery at 4p.m. The winter has been mild, and it’s not inconceivable that a GBH could have survived the winter locally.

1SE02. At 10:30 p.m., a great blue heron in Geneva, standing in shallow water in the Fox River, apparently fishing in the street lights.

16JE03. This year I know of 2 large nesting colonies in DuPage County, both established in recent years. One is at Danada Forest Preserve, the other at Pratts Wayne Woods, near the intersection of Rt. 59 and Stearns Road and visible from both.

8AU03. I kayaked between Willow Springs Road in Cook County and Route 83 in DuPage on the Des Plaines River. There is a strung-out colony of great blue herons nesting over a 2-mile stretch of river that spans the county line. The nests are in scattered dead trees close to the riverbank, taller than the surrounding trees, 2-5 nests in half a dozen trees total. Though separated sometimes by more than a hundred yards, the trees each seem to have one of the others in view.

28MR06. At Tri-County State Park, the 2 nests from last year (a new satellite of the Pratts Wayne colony) gradually had lost most of their sticks. On the 23rd, herons returned (later than in the larger colonies), and now are building the nests back up. One seen carrying a long thin stick in its beak, flying up to a perch beside the nest and giving it to its mate standing in the nest, who then added it. Two additional pairs perching in those trees, but no new nest starts yet.

18JA09. Danada. Checked great blue heron rookery. Most of the 15-20 nest trees were living cottonwoods, and 90% of the nests were in these. Two were dead trees, and three were willows. One cottonwood had 16 nests, a couple had 13, one had 11. Total nests counted 142. The rookery is in a swampy area around a large pond. Last summer I also learned of a rookery at Churchill Forest Preserve, on the islands in the East Branch of the DuPage River.

11OC10. During a dragonfly monitoring run on the Des Plaines River I noticed that, in addition to the scattered great blue heron nests in tree tops along the shore, there is at least one group of trees with a number of nests in a more concentrated colony. There are more than a dozen nests in at least 3 adjacent trees. This cluster is on the river’s south bank, east of Route 83.

October Monitoring Run

by Carl Strang

Last weekend’s warm weather allowed me to make a late dragonfly monitoring run on the Des Plaines River at Waterfall Glen Forest Preserve. Looking back through my records, I find that in all the monitoring I have done since 2003, I never have made a formal outing in October. It was worth trying for that reason, if no other. Besides, it was a nice day to be on the river in my sea kayak. There isn’t a lot to report as far as dragonflies and damselflies go. The only dragonflies were a pair of common whitetails, the female laying some last ditch eggs. I saw a couple familiar bluets,

a few orange bluets,

a stream bluet, 3 eastern forktails and 7 American rubyspots.

The last confirmed that this species is active late in the season, supporting my sighting at Fullersburg (which at first I thought was a smoky rubyspot). I also made some singing insect observations, the best of which were jumping bush crickets singing in the early afternoon on both sides of the river. This adds to my local range for this species, which clearly has shifted north of where you will find it mapped in references. The shallow lagoon at the downstream end of my monitoring area was hosting a gathering of great egrets.

The gorilla in the room, however, was a major construction project underway on the south side of the river. A fence was being built.

With much machinery, much shouting and an impressively speedy progress (I saw no sign of this when I last was there in late August), a metal framework is being erected and filled with fine-meshed screening.

The fence is parallel to the Centennial Trail, which has been closed for this project. The fence is only 6 feet tall or so, enough to disrupt the view of trail users but not enough to be a significant barricade to wildlife, I thought. A little research on the Internet revealed the purpose of this structure. It is a fish barrier. That may seem strange, but high water levels could lift the river high enough to reach the fence. The target fish are Asian carp, a group of 4 species which have been much in the news because of concerns that they might cross from the Mississippi River drainage (which includes the Des Plaines) and the Great Lakes. The Des Plaines River is paralleled by a canal, so the fence apparently is intended to keep the carp from going between the two. Would tiny baby carp be stopped, though? I’m not enough of a fisheries biologist to judge. For more information on the fish species and other information, here is a link.

Kayak at Last

by Carl Strang

I was beginning to wonder if I would get the opportunity to put a paddle in the water this year, but circumstances allowed me to run my dragonfly monitoring route on the Des Plaines River at Waterfall Glen Forest Preserve this past weekend. Of course, in the context of this blog the monitoring is the main thing, but on a personal level it’s been hard to go almost a year without paddling. My sea kayak has taken me through north Georgian Bay.

It’s given me sights like this, Devil’s Island in the Apostles of Lake Superior.

On Sunday afternoon the sea kayak Water Strider was my vehicle yet again. I found no new species, but was interested to find that the counts for various species fell between the values for last year’s August 2 and September 3 counts, despite other measures of phenology generally placing this year earlier than last. Common whitetail and eastern amberwing dragonflies were closer to the August 2 count, though both exceeded any of last year’s counts for those species. Powdered dancers and stream bluets fell between the counts of last year’s dates. Familiar bluets were closer to the September 3 count. Many, like those in the following photo, were ovipositing.

Skimming bluets showed a significant increase, with 10 counted on this trip against 1 for the entire 2009 season. In contrast, jade clubtails were missing this time, and orange bluets were few. I wonder if their seasons are done for this year.

Back to the River

by Carl Strang

Last week I made my fourth dragonfly monitoring excursion of the season by kayak on the Des Plaines River (last updated here ). It was a pleasant, early autumn day. Practically nothing was happening over the center of the river, but there was more action near shore. I found only two dragonfly species. Eastern amberwings remained common, and I also saw a few jade clubtails. Here is one of the latter.

Jade clubtail 3SEb

September 3 is a late date for that species. Damselflies were common, and in general were the same species I had seen on the previous outing in early August. The only new species was a tiny skimming bluet, which perched for a time on my deck line.

Skimming bluet 3SEb

Otherwise, highlights included patches of halberd-leaved rose mallows,

Halberd-leaved rose mallow b

and the best surprise of all, a single sandhill crane hunting in one of Waterfall Glen’s marsh streams.

Sandhill crane 2b

I hope to get on that river at least one more time this year.

Fishin’

by Carl Strang

The art of fishing is, I argue, a primal form of inquiry: primal because of its tie to The Next Meal, and inquiry because of the practical questions that can be answered only through experimentation. Where can I catch a fish? When can I catch a fish? What bait and other methodology will help me succeed in catching a fish?

I see eagerness in Roger Raccoon Club  members as they get their opportunity to fish on the second afternoon of the camp.

RRC fishing 2b

This is a picture from a couple years ago. In this year’s second session I was too busy to take a picture. I suggested that the kids try live bait vs. a scent-treated artificial bait, both of which I provided. From that point forward my own experience was two solid hours of baiting hooks, untangling lines and unhooking fish. So, all I have are the kids’ reports that the artificial bait was a complete failure compared to the live bait. Of course, the fish at this pier are thoroughly kid tested. They see every kind of bait every day, and are expert at discerning the real deal and stealing it from hooks.

Last weekend, as I reported yesterday, I made my third dragonfly monitoring excursion on the Des Plaines River via kayak. My deck included a little extra equipment.

Deck with fishing rod b

After the monitoring was done, I had a little time for some fishing as I made my way back to the launch ramp. I used a different kind of plastic bait impregnated with scent. I had tried it before without success, but never here, never now. I got a bite. The fish was not a jumper. It stayed deep until I got it to the boat.

Channel cat 2b

Of all things, I had caught a channel catfish. In the muddy waters that flowed that day, the cat had found the bait by scent and was sufficiently fooled by it to bite. The fish looked eating sized, but I was in catch-and-release mode that day.

I don’t do a lot of fishing, so it was no surprise that I sensed a little boy jumping up and down inside me who wanted to tell the RRC kids: “I caught a bigger fish than you did!”

Dragonfly Monitoring Update

by Carl Strang

Earlier I described  my first venture into dragonfly and damselfly monitoring by kayak. I have been out on the Des Plaines River twice since then. There has been some variation in the count of species and individuals each time, but most seems unremarkable. I’ll focus on a couple high points. The biggest surprise was a transition in the damselflies. The slender bluet was the common black type bluet my first time around.

Slender bluet 5JL 1b

Bluets are a group of small to medium sized damselflies. Black type bluets are so called because their abdomens are nearly all black as viewed from above. On my second and third outings, the slender bluets were replaced by stream bluets as the common black type bluets. Here is one of the latter I rescued from the water.

Stream bluet 23JL09 1b

Note that, in contrast to the slender bluet in the top photo, the stream bluet has a slender blue shoulder stripe with a wider black stripe below it. “Eye spots” on the back of the head are smaller in the stream bluet, and there is less blue in the abdomen tip. Stream bluets were largely in tandem pairs and actively laying eggs on floating vegetation during both recent outings.

Stream bluets tandem b

The other surprise is the relatively large number of orange bluets. Here is one sharing a photo with a stream bluet.

Orange and stream bluet b

I’m not saying that the river is swarming with them, but in my experience a count of 13 orange bluets in a 2-hour outing is a lot. A final note is that eastern amberwings have become the most abundant dragonflies, despite my seeing none on the first outing. Here is a photo of one from 2007.

Eastern amberwing male 2b

I have decided to limit my monitoring to the stretch of river that bounds Waterfall Glen Forest Preserve. This gives me a span of stream between the launch ramp and the preserve in which I can practice another type of inquiry, to be featured tomorrow.

“Annual” Cicadas

by Carl Strang

The late summer days are marked by the droning songs of cicadas in the genus Tibicen. Unlike the periodical cicadas, which appear at 17-year intervals, some of these emerge each year. They sing from concealed perches high up in trees, so we seldom see them alive. Here is one I found shortly after its emergence from the ground on a rainy day at Fullersburg in 2007.

Tibicen linnei live 1b

This is Linne’s cicada, Tibicen linnei. Its drone is a rapid vibrato, and it has a wide range of habitats, so you can find this common species just about anywhere there are trees. There are three other common cicadas in this group in northeast Illinois. The one with the song closest to linnei’s is the lyric cicada, Tibicen lyricen. The songs are so similar, in fact, that it took a couple seasons for me to realize this was more than just variation within a species. Here is a specimen of lyricen.

Tibicen lyricen 1b

Note that the narrow collar behind the head is black. In the other three local species it is green. T. lyricen also has larger areas of chocolate brown just behind the collar. Its song has an even more rapid vibrato than linnei’s, sounding to my ear like a buzz saw. Song length is different, too. The vibrato portions of linnei songs are 15 seconds long at most (of 29 songs I have timed, only one reached 15 seconds). T. lyricen songs can be more than a minute long; the shortest of 24 songs I timed was 18 seconds. Median song lengths for the two species were 9 and 24 seconds, respectively. The lyric cicada can reach huge densities along rivers, being the most abundant Tibicen along the Des Plaines River at Waterfall Glen Forest Preserve, for instance. They also occur around lakes such as those at Mayslake. Usually they are close to a body of water. Another abundant, wide ranging species is the dog day cicada, Tibicen canicularis.

Tibicen canicularis 1b

This one looks very similar to linnei; it is the smallest of the four species. Its song is a high-pitched tone, siren-like, the vibrations occurring so rapidly that there is no vibrato. Song length is short.

I have no photo of the fourth species, the scissor-grinder cicada, Tibicen pruinosa. Though widespread, its numbers always are much smaller than those of the others. I have yet to see one, alive or dead (the photographed specimens were collected dead on the ground by my DuPage Forest Preserve District naturalist colleague Leslie Bertram). The scissor-grinder is the largest of the four. Its song is very distinctive, consisting of long pulses, rising and falling at 1-2-second intervals.

These cicadas all sing in daylight, quieting after dark. The lyric cicada begins early, peaking its singing in the morning but continuing in smaller numbers into the afternoon and evening. Peaks for Linne’s and dog day cicadas are in the afternoon, but they continue to dusk, and a few may start early in the day. The scissor grinder peaks its singing in the late afternoon to dusk, but can be heard at mid-day, too.

For recordings of these cicadas’ songs, go to the Michigan cicada web site  or the Songs of Insects site.

Dragonflies on the Deck

by Carl Strang

I have been part of the regional dragonfly monitoring program since it began in 2003. I started counting dragonflies and damselflies at Willowbrook, Songbird Slough and Waterfall Glen Forest Preserves, in recent years focusing on the last two. Though I continued to find new species from time to time, the past couple of years I have felt the need to try something new. The major gap in my knowledge was in river species, so this year I decided to combine my loves of kayaking and dragonfly monitoring by trying out a river route. Water levels have been high, and cool weather has been suboptimal for monitoring, so I didn’t make my first excursion until last weekend. I launched my sea kayak from the forest preserve boat ramp at Des Plaines Riverway, and headed downstream into Waterfall Glen Forest Preserve.

Des Plaines monitor view b

Experienced kayakers know to tie everything to the boat. I didn’t want to risk wetting my digital voice recorder, so I tied a waterproof notebook to a deck line, tied two pencils to the notebook, wore my waterproof small camera and binoculars, and tucked everything else into my yellow deck bag.

Monitor deck 1b

I used the strongest current in the center of the river to go downstream, taking moments along the way to enjoy sights such as scattered great blue heron nests.

GB heron nest Des Plaines b

The only American rubyspot of the day made it easy by landing on my bow.

American rubyspot kayak b

Dragonflies were tougher, however. The low, seated vantage point made flying dragonflies look different, and it took a while to recognize even familiar species. They were flying fast over the center of the river, making photography impossible, and even tracking them with binoculars was very difficult. My frustration was limited by the low number of insects active in the center of the river that day. I reached a convenient turn around point after an hour, and started back following the sunlit north shore. (Current is slower near the bank, making the upstream paddling easier.) Odonata were much more abundant along the edge. Some damselflies continued to land on the boat. Here a powdered dancer and a blue-fronted dancer chose to land on the deck bag, providing a comparison shot.

Dancers kayak 1b

Other damselflies kept their distance, landing on sticks or debris. The small camera’s telephoto was adequate to get shots of the abundant blue type bluets, which proved to be familiar bluets.

Familiar bluet 5JL 1b

There also were many black type bluets, which I identified as slender bluets.

Slender bluet 5JL 1b

The most abundant dragonflies were jade clubtails, some of which liked my deck.

Jade clubtail kayak b

I was pleased to see a Cyrano darner along the way, though I was unable to get a photo. Toward the end I got a nice view of some Illinois roses.

IL roses Des Plaines b

All in all there was a nice variety of species, most of them familiar but some I missed. I look forward to a continuing learning experience as I return to this route on future weekends.

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