Wetland Singing Insects Update

by Carl Strang

For years, now, my biggest conservation concern among the singing insects has been in the wetlands. Though our historically abundant prairies in the Chicago region were diminished nearly to nothing by 19th– and 20th-century agriculture, preservation and restoration projects across the region have halted and, to a small degree, reversed that trend. The same could be said for savannas, and our forests did not suffer as much.

Wetlands, like prairies, declined thanks to agriculture, but a new challenge continues to threaten their integrity: invasive wetland plants. Four of these are especially problematic: common reed (Phragmites australis), reed canary grass (Phalaris arundinacea), hybrid cattails (Typha x glauca), and purple loosestrife (Lythrum salicaria). These plants, released from consumers and competitors, have displaced the diverse native species in a large and increasing portion of our wetland acreage. The loss of native wetland grasses, especially, appears to account for the difficulty I am experiencing in finding wetland katydids.

Reed canary grass

Two species that were here historically, I have not found at all: the delicate meadow katydid (Orchelimum delicatum), and the slender conehead (Neoconocephalus lyristes). In the past these were known to occur in four and three, respectively, of the Chicago region’s 22 counties, and I am nearly out of places to check where they might still live. The stripe-faced meadow katydid (O. concinnum), once found in 8 of the counties, appears to be down to a single population at Illinois Beach State Park.

Stripe-faced meadow katydid

Two wetland katydids are doing well. Gladiator meadow katydids (O. gladiator) and black-legged meadow katydids (O. nigripes) are tolerant of the invasive plants, and remain common in every county.

That leaves an in-between category of wetland singing insects that apparently are limited to invasives-free wetlands, and are managing to hang on in a few to several sites. Northern mole crickets (Neocurtilla hexadactyla) occur in wet prairies as well as marshes. In 2017 I added records for two more sites, one of which represented an additional county record. To date I have found them in 10 counties, and remain optimistic that I can add more populations to the inventory.

Dusky-faced meadow katydids (O. campestre) historically were ubiquitous in our marshes. To date I have found them only in marshes with minimal impact by the invasive plants. These katydids seem able to persist in relatively small wetland areas, however, and each year I have been able to add new populations to my list. In 2017 I found them in the Indiana Kankakee Sands preserve, adding Newton County to the record, and in the Tefft Savanna preserve in Jasper County, also a county record. That brings to seven the number of counties where I have found the species, but there are seven more where it once lived, but where my search has been unsuccessful. Dusky-faced meadow katydids also proved this year to be abundant in the panne wetlands at West Beach in the Indiana Dunes National Lakeshore. That was a good find, but I had hoped for delicate meadow katydids there.

Female dusky-faced meadow katydid, Tefft Savanna

Finally, this year I added a third population and county for the nimble meadow katydid (O. volantum). They were singing from arrowheads (Sagittaria sp.) mixed with cattails along Grant Creek in the Midewin National Tallgrass Prairie. That find was made from a kayak, and that is the vehicle from which further searching for the species will need to happen, as this species likes plants growing in relatively deep water. Some places which historically held nimble meadow katydids no longer have them, but several other sites remain for me to check in future years.

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Wetland Concerns

by Carl Strang

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.

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.

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.

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.

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.

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.

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.

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.

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.

Winter Botany Update

by Carl Strang

Every species we see in summer persists through the winter. In the case of plants, which cannot migrate, they are present in the landscape, though in some cases they are not readily visible outside the growing season. Nevertheless, most can be seen. Some are little changed.

Austrian pines, among the many exotic conifers planted at Mayslake Forest Preserve, are equally easy to identify in all seasons.

Some herbaceous plants remain green in winter. While the rosette form, with leaves held close to the ground where they can gain some protection from sheltering snows, is more common among forbs, one of Mayslake’s sedges, the common wood sedge, has a rosette-like habit.

The tips of the leaves have browned, but otherwise this sedge looks ready to go when spring arrives.

Some plants, though brown, are unmistakable. I was not pleased to find three small patches of common reed at the south edge of the preserve.

This plant, once established, spreads to push out all other wetland plants.

These will need to be attended to, and I was happy to learn that Mayslake’s restoration team has reported them to the Forest Preserve District’s natural resources staff.

My greatest botanical delight in recent weeks was encountering this tall, odd looking plant.

The pods place it in the legume family, but it was totally new to me.

Thanks to a heads up from Scott Namestnik I can correct my initial identification to wild senna. This is Mayslake’s second species of Cassia (some botanists separate it into genus Senna), and I look forward to seeing its bright yellow blooms next summer. (Initially I had identified it as indigo bush, another tall streamside legume, but the pods of indigo bush are proportionately much wider in comparison to their length).

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