The Dead River, in Illinois Beach State Park, is so named because most of the time it appears not to be flowing. It ends just shy of the edge of Lake Michigan, a sand bar between the two. Reportedly there are times when enough water comes into it that it breaks through this narrow barrier. The area south of that river is highly protected, and to enter it I needed a permit from the Illinois Nature Preserves Commission.
The Dead River and its extensions are free of invasive wetlands plants, though there are some unconnected wetlands in the area for which that is not the case.
Sand savanna and prairie occupy the spaces between the wetlands.
My main goal was to survey the area for wetland singing insects. This was one of my last hopes for finding slender coneheads, but sadly there were none. I am beginning to think they have gone extinct in Illinois. On a much brighter note, I found that the area harbors a huge population of stripe-faced meadow katydids.
This male had developed his full facial color, but an intervening grass blade marred the portrait.
Profile view of a female.
Illinois Beach remains the only place where I have found this wetland katydid, which even historically was never widely distributed.
I also heard a little chorus of nimble meadow katydids, out in the middle of a river offshoot in a patch of deeper-water arrowheads. There probably are other such groups elsewhere in the area. I plan to get a better idea of their numbers next year. This is the second place I have found them in the region, and the first for Illinois. I spent several days in my kayak this season searching for nimble meadow katydids in places in Illinois and Indiana where they were known in earlier decades.
Apparently the American lotus, shown here, and the yellow pond lily, which filled most of those sites, are too coarse for nimble meadow katydids.
I have found them among pickerel weeds and arrowheads, and historically they were known in patches of water knotweeds.
Water knotweed, like those others, is of intermediate coarseness.
I suspect that the turbulence created by power boats favors the heavier plants that the insect apparently abhors. I wonder if Illinois Beach State Park also may harbor the last Illinois population of nimble meadow katydids. I have a few more places to check next year.
After leaving Sarett Nature Center I drove down to central coastal Berrien County. A GoogleEarth study of the southern Lake Michigan shore had pointed to Grand Mere State Park as a site with wetlands that might contain some of the rarer meadow katydids. As it happened, I missed one of the signs pointing to the park entrance, and found myself on a road bordering a small lake. This proved to be a lucky accident. I stopped at a sandy informal boat launch, and when I waded out a short distance I heard unfamiliar buzzes coming from a patch of pickerel weeds.
A few bulrushes and water knotweeds were mixed with the pickerel weeds.
I soon found that the water was too deep for my knee boots, which rang a bell. I quickly changed out for hip boots, grabbed sound recorder and camera, and returned. Here is what I heard:
It reminded me of the song pattern for the woodland meadow katydid, except that the ticks between the buzzes were fewer, and I could hear the song clearly unaided (i.e., without needing the pitch-lowering SongFinder device). By this time I was sure I must be hearing nimble meadow katydids. Very little has been published about them. Morgan Hebard in his 1934 monograph on Illinois Orthoptera said he found them only where the water was waist deep (hm, now that I think about it, he did not give his height). I had searched for them by kayak in a few places, without success. As I waded out I found the pickerel weed patch was in water knee to mid-thigh in depth. I also found that both hip boots were leaking. I began getting glimpses of the katydids, and soon discovered they were well named. They were quick to fly, and flew up to 20 feet. One did something totally unexpected: he dove beneath the water and hid among the submerged stems.
Eventually I was successful in getting some photographs, and in catching a katydid for cerci shots.
Nimble meadow katydid. The head is colored like that of the black-legged meadow katydid, the hind femora green like those of dusky-faced meadow katydids, but with brown tibias, and it is the same size as those species, but the most distinctive feature is the yellow end of the abdomen, reminiscent of the much smaller short-winged meadow katydid.
This is the best I could do on a ventral cerci shot, balancing in the leaky boots and holding the struggling critter with one hand while manipulating the camera with the other. Note the beautiful colors, and the distinctive shape of the pointed, brown-tipped cerci.
The song is not so loud that I can expect to hear it from more than 15-20 feet away, but the fact that I can hear it unaided will be a huge help in future searches. The nimble meadow katydid’s adaptation to beds of emergent plants in deeper water means that its main threat probably is not invasive wetland plants but rather the mechanical disruption of habitat by power boats, waves bouncing off sea walls, and the like.
I was out of time. Grand Mere State Park still holds promise, and I look forward to returning next year.
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.
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.
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.
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.
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.
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.
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.
It should be obvious that this title is not a political reference. In this election year both political conservatives and liberals are easy to find as they loudly and shrilly make their cases against each other, trying to attract voters (hm, reminds me of singing insects for some reason). The conservatives I am concerned about here are some of the wetland species of singing insects, habitat specialists that are found only within narrow ranges of ecological parameters and are sensitive to invasive species and other disruptions. Much of my research this year is focused on finding conservative species from my hypothetical list for the region.
I haven’t had a lot of luck with wetland conservatives. The northern mole cricket was one, but I still have not found them anywhere but Houghton Lake. The marsh conehead was another. We thought we also found slender coneheads at Indiana Dunes National Lakeshore, but Gideon discovered when he returned to his lab that they all were marsh coneheads as well, misleading because they were outside the size range of that species he was familiar with in Missouri.
Gideon also learned that the underside of the cone should be black, not gray as it was on the marsh coneheads we found.
But what about the several species of wetland meadow katydids in genus Orchelimum? Regionally there should be four species I haven’t yet found: dusky-faced, stripe-faced, delicate and nimble meadow katydids all have been elusive. I should have found dusky-faced meadow katydids, at least, because they are described as being common in a wide range of marshes. Instead I am finding lots of black-legged meadow katydids, a marsh species that spills into drier areas adjacent to wetlands.
Black-legged meadow katydid
Black-legs sing so loudly, day and night, that I wonder how earlier researchers heard the other wetland species. I wonder if black-legs have become more abundant, conceivably pushing the others out. Have I not been looking in the right places or in the right way? Is the lack of success this year a consequence of the drought? Certainly it takes some effort this year to get wet feet in the marshes. I will continue to look. Last week at Chain O’Lakes State Park in Illinois I saw a number of Orchelimum nymphs that were relatively plain and green.
This female meadow katydid nymph is recognized as an Orchelimum by the curved ovipositor.
On the other hand, black-legs don’t get their full colors until after they mature.
This newly molted adult male black-legged meadow katydid still has not developed his full coloration.
I will continue to look this year, and hope for better conditions next year.
In recent weeks I have been reviewing species of singing insects which the literature indicates may occur in northeast Illinois or northwest Indiana but which I have not yet found in my own survey. This week’s example is the nimble meadow katydid.
This map from the Singing Insects of North America (SINA) website shows our area to be in the center of this katydid’s known range. As has been true for many species, a narrow habitat preference appears to be the reason this one is encountered less often than others. Nimble meadow katydids reportedly are restricted to emergent or overhanging vegetation at the edges of open water. In fact, Hebard in his 1934 review of Illinois Orthoptera said it was found only where vegetation protruded from water at least waist deep. He had it in only 2 northeast Illinois locations in northern Lake and McHenry Counties. This points to the Chain o’Lakes State Park area along the Fox River. All Illinois records for the species in the SINA database are dated 1934 or older. The same is true for Indiana, except for one from Starke County (Bass Lake? Kankakee River area?). Otherwise, the old Indiana records include Marshall (Lake Maxinkuckee) and Fulton counties.
The nimble meadow katydid gives me an excuse to search from my sea kayak next summer. Two accessible places to seek it, along with other rare wetland species, are Lake Maxinkuckee (the Venetian Village area) and Chain o’Lakes State Park.