Roesel’s Katydid Trip, Part 2

by Carl Strang

Having established a new Tippecanoe County southern limit to the known distribution of Roesel’s katydid in Indiana, as I described yesterday, on Thursday of last week I went farther south to seek them in Montgomery County. I stopped at several patches of habitat along the highways, but though I heard plenty of spring field crickets and kicked up numbers of tiny grasshoppers, I found no Roesel’s.

Here is an example of one of my stops. This area of several acres was, to my eye, just like the Purdue site and others where I have found abundant Roesel’s katydids farther north. None here, though.

I parked at Shades State Park, hiking the beautiful trails there as I waited for the temperature to rise.

Sugar Creek from an overlook on one of the Shades State Park trails.

Shades, like its more famous neighbor at Turkey Run, features interesting little canyons carved through sandstone and shale.

The sandstone wall of a canyon.

It was nice as well to hear the songs of birds I don’t often encounter in northeast Illinois. At mid-day I hopped on the bike and set out. It was fairly windy, though not nearly as bad as on the previous day, and I expected to hear Roesel’s if they were present. In a ride of more than 15 miles, though, I found only one little group of 3 singing males. I stopped and waded through the grass, but it was dense and tall, and the katydids were down low, perhaps to avoid the wind, so I wasn’t able to see them and assess their wing lengths.

On Thursday I shifted still farther south, to Johnson County (the next county south of Indianapolis). I drove all around the Atterbury Fish and Wildlife Area through the morning, again stopping often to look for Roesel’s in likely looking habitat patches, but found none. I have no photos; this area is interdigitated with the Camp Atterbury military base where photography is forbidden.

Again at mid-day I went for an exploratory bike ride. It was a little cooler, reaching only the upper 60’s, but I should have heard Roesel’s if they were there. I heard none, despite a very high proportion of roadside lined with suitable habitat. I cannot say they don’t occur in Johnson County, but for now I am inclined to think they may be only in the north half of Indiana.

Roesel’s Katydid Trip, Part 1

by Carl Strang

I reserved some vacation days for last week, to continue probing the range extension of Roesel’s katydid. As detailed in earlier posts, I have been exploring this European species’ geography, beginning in 2007 when I found some in north central Indiana, a state in which they apparently were previously unknown. Since then I have been joined by Scott Namestnik and others, and we have connected Illinois’ Roesel’s, once thought to be a separate population, with the extensive range of the katydids in the Northeast. We still needed to find out how far south they have spread, and also to probe the suspiciously empty lower peninsula of Michigan in Roesel’s range maps.

On Wednesday I drove down to Tippecanoe County and Purdue University, where I went to school. It didn’t take long to find abundant Roesel’s just outside the main campus, at a “new” (keep in mind I was a student there in the 70’s) tennis and cross country athletic facility.

Between the mowed lanes of the cross country course were areas with tall grasses and forbs, ideal Roesel’s habitat.

I heard numbers of singing males, and as I walked along the edge spooked others into jumping. I saw short-winged and intermediate-winged individuals of both genders, but no long-winged katydids.

Here is a short-winged female at the Purdue site.

There has been much speculation in the literature about how the rapid spread of this species would seem to have been done by the long-winged form, rare in the original European range but more common in North America. It is not established whether the age of a local population can be tied to the distribution of wing lengths, however.

That afternoon I went for a bike ride in the northern edge of Tippecanoe County. I heard only a couple Roesel’s along the way, but the wind was very strong, gusting to maybe 30mph, so there may have been many more I didn’t hear.

Cicada Update

by Carl Strang

Periodical cicadas in small, scattered numbers have continued to appear in a large part of DuPage County. Steve Bailey, who conducts bird surveys for the state, also has heard them in parts of Grundy and southern Cook County. So far nearly all have been singing the cassini song type, except for one septendecim-like singer reported from Fullersburg Woods Forest Preserve by Naturalist Leslie Bertram.

There are so few that prospects for reproductive success are dim.

This is the expected fate for nearly all of these vulnerable individuals, to be eaten by birds, their wings plucked off and dropped to the ground.

I witnessed such a predation event myself at Mayslake Forest Preserve. A cicada got in maybe four songs before a robin flew straight to it. The insect got out an alarm squawk, then all was still.

In an earlier post I speculated about what was going on with these cicadas, which had been quiet the previous two years. A suggestion by WBEZ radio news director and nature enthusiast Brian O’Keefe reminded me of similar ideas expressed in the scientific literature when cicadas appear outside their brood’s normal area: perhaps these were transported from the southern brood XIX range in the root balls of nursery stock. That certainly could account for the ones in residential areas and in portions of forest preserves adjacent to private lands. I checked with the Forest Preserve District of DuPage County’s nursery staff, however, and none of our tree plantings in the past 13 years have come from so far south. Some of these cicadas are half a mile or more from the nearest preserve boundary. A little mystery therefore remains, but I have concluded that my time would be better spent in other directions.

Incidentally, while documenting these scattered emergences I was listening for green-winged cicadas (Diceroprocta vitripennis), another spring species which I believe emerged in small numbers in 2007. Their buzzings were largely covered by those of periodical cicadas, however, and the only hard evidence was a single wing, like the one in the photo above, but with green rather than red veins. Some of the literature suggests a 4-year periodicity for Diceroprocta, but I have encountered none in the places I thought I was hearing them in 2007.

Birds Around the Marsh

by Carl Strang

The area with the greatest diversity of birds at Mayslake Forest Preserve, now that the breeding season is well underway, has been the stream corridor with its adjacent marsh. The corridor itself is wooded, attracting Baltimore orioles, warbling vireos, yellow warblers, common yellowthroats, indigo buntings and downy woodpeckers.

This male downy worked on a nest cavity earlier in the season.

The marsh itself has been a place of interest. During the earlier part of the migration it held a pair of buffleheads for two weeks. More recently I saw one of the most unusual birds of the year there, the preserve’s first least bittern (gone before I could get the camera up; I wasn’t going to pursue and harass it just for a photo).

On Friday the marsh had a trio of herons. I didn’t get a photo of the great blue heron, which nervously departed as soon as I came into view. I had better luck with the green heron.

He landed on this stub after being chased from a preferred corner of the marsh by the bird in the following picture.

The third heron visits Mayslake less often than the others.

Great egrets always are a welcome sight, perhaps to be seen more often in summer now that they are nesting in DuPage County.

I have been most fond of another little group of birds, a momma wood duck and her young.

She started out with 9 ducklings. Only 4 remained when I took this photo.

With the diversity of birds, plants and insects around that marsh, it has been my favorite part of the Mayslake preserve this year.

Deer Make Camp

by Carl Strang

In May I mentioned white-tailed deer tracks that were the first signs of that species on the Mayslake Forest Preserve in about a year. Deer have been present consistently since then, though the numbers have dropped to two. I got a glimpse of them last week. As expected from the timing and clues in the footprints, they were bucks, a big older individual already with significant antlers, and a yearling with buttons at best. On Friday I ran across a bed.

This was a well-placed resting spot, away from people and close to both food and a wooded travel corridor.

They may or may not stay for the summer. Bucks wander more than does, though sometimes not so much in summer when food is easy to find.

The American Snout, and More

by Carl Strang

One of my favorite animal names is “American snout.” It calls forth the image of some disembodied nose floating in space. In fact it’s a reference to a butterfly with a long forward extension of its head.

This butterfly was the first of its kind I have observed at Mayslake Forest Preserve. It is more common south of us. In references you may find its species name as carinenta or bachmanii; the genus is Libytheana, and there is only one North American species.

Another preserve first was this brightly colored beetle.

The milkweed leaf beetle, like so many consumers of milkweed, has bright orange colors. These warn potential predators of the possibility of poisons the insect may have sequestered from its diet.

I saw a couple bluets that had the relatively large size and the color pattern of familiar bluets.

The males had this violet coloration, though; my guess is that they had recently emerged as adults and would be changing colors soon.

I have been seeing more Virginia ctenucha moths than usual this year, at Mayslake and elsewhere.

That’s the way it is with some insects, having occasional years with higher numbers.

Of course, a major goal of all these adult insects is to find a mate and produce eggs.

For this pair of least skippers, it’s so far, so good.

On Friday I finally saw the first Peck’s skipper of the year.

The pattern of light spots beneath the hindwing is distinctive for this species.

It’s been a good year for insects, so far.

Grasses, Easy and Hard

by Carl Strang

Grasses are a pain. I thought that Carex sedges would be my big botanical challenge this year, but they are a breeze compared to grasses. As in all groups, you have to wrestle with the plants and identification keys to get a grip on what the authors of those keys are talking about. They’re not all so difficult, however.

This grass was refreshingly straightforward. All those long hairs, and the little round 1-flowered spikelets, pointed the way to old-field panic grass, Panicum implicatum.

Growing beside that grass in Mayslake Forest Preserve’s north savanna was another that was more challenging.

I had watched as this delicate looking plant developed, and some finally produced their first anthers, so I pulled a stem to identify.

Looking back, I can see that I learned a lot from this grass, but only after much frustration, quitting at least three times and stubbornly going back for more. I found that it had a tuft of cobwebby hairs buried inside the flower, pointing to Poa as the genus, but that tuft was very small compared to the obvious one in Kentucky bluegrass, which I had identified earlier.

The reproductive parts are contained within tiny leaflike structures called lemmas, and the number of veins on the lemmas, how distinct they are, and whether they have hairs on them are important characters to distinguish species in this genus. It took a while to get there, and I had to lean on a lot of other features, but ultimately I came up with Canada bluegrass as the ID. Its scientific name is Poa compressa, and the stem indeed is very flattened out as that label suggests. I hope it gets easier with experience. If nothing else, having learned to identify these species, they reduce the list of possibilities next time.

Thanks, Dad!

by Carl Strang

Last year I broke out of the usual realm of this blog to pay tribute to my Mom for Mother’s Day. This year it’s Dad’s turn.

Ted L. Strang’s favorite activity always was fishing.

Dad can’t handle fishing tackle any more, and his memory isn’t what it used to be, but he maintains a positive attitude. He was a rock when supporting Mom as she went through her health crisis last year. I have Dad to thank for much of my interest in the out-of-doors.

Dad passed on the outdoor traditions of hunting and fishing to my brother and me. Here he poses with the ducks from a day’s hunt, a few years after returning from World War II and a year and a half before I was born.

I’ve done my best to return the favor.

In the years when he still maintained his own pier but could no longer put it out or take it in alone, I helped. It was a small return.

My parents don’t have a computer. I express my gratitude to them directly. But it’s appropriate to acknowledge that I wouldn’t be here, and this blog wouldn’t exist, without the grounding I received, in the woods and fields, on the lakes and rivers, from my Dad. Happy Father’s Day!

Riding the Great Lacuna

by Carl Strang

One of the many little mysteries I puzzle over is the spotty local distribution of field crickets. We have two species, the spring field cricket and the fall field cricket, in northeast Illinois. They look alike, sound alike, and are active in different parts of the season. Though they prefer much the same habitat, and more often than not occur together, sometimes one of the two species (usually the fall field cricket) occurs alone.

Green circles mark DuPage County locations where I have found both spring and fall field crickets. Blue circles indicate where only spring field crickets occur, and yellow circles mark spots exclusive to fall field crickets. The red area and blue star are explained below.

You can see that in east central DuPage County I found only fall field crickets through 2010. The yellow circles mark York Woods Forest Preserve (the northernmost circle), and in a row from east to west: Fullersburg Woods, Mayslake, Lyman Woods and Hidden Lake Forest Preserves. Together they seem to define a space, or lacuna, where spring field crickets may be absent. On Monday I rode my bike between these locations, listening as I went for field cricket songs. Though much of this area is occupied by gated residential communities, the city of Oak Brook also maintains a fine system of bike paths which allowed me to zigzag through much of the zone marked in red on the map.

I found mainly mowed lawns, residences, woodlands and businesses (including the McDonald’s corporate headquarters and “Hamburger U”), but there were plenty of places just like ones in which I have heard numbers of spring field crickets elsewhere, with unmowed grasses or mixed grasses and forbs. In all that area, though, I heard only two crickets singing, close together in the location marked by the blue star on the map. That spot marks the northern extent of a zone I should investigate further, between the Fullersburg and Mayslake preserves.

Still, it seems the lacuna is indeed largely empty of spring field crickets. Next steps will be to find how far the boundaries of this area extend, and to look at old aerial photos for clues as to why this region might be different, keeping in mind that fall field crickets are present. I may repeat yesterday’s bike ride in the late summer or fall to see if fall field crickets occur in the spaces between those preserves.

Newly Appearing Insects

by Carl Strang

The weather rollercoaster we have been experiencing (for instance, last week’s drop of 40 degrees F in less than 24 hours) has not deterred insects from stepping onto the stage at Mayslake Forest Preserve. Some of these have been familiar, and more or less on time compared to earlier years.

The viceroy butterfly is not particularly common at Mayslake, and I have found it hard to approach. This one, for a change, held still long enough for a photo.

Another expected species is the jade clubtail.

Usually these perch on shore, or on a log or rock protruding from the water, but an algal mat sufficed for this one.

Totally new to my experience was this insect.

At first glance I thought it might be an unfamiliar bumblebee.

Then, having found it to be a fly, I was going to call it a robber fly.

Many robber flies are bumblebee mimics, but this insect lacked the predatory beak.

A search of my references placed it in the syrphid fly family, but there were at least 4 genera that might fit, and my photos didn’t provide enough detail for me to narrow it down. The densely orange hairy thorax was unlike any species I could find.

Most photos were, sadly, blurry like this. Clear images of the antennae and wing veins would have been most helpful.

I submitted a photo to Bug Guide, hoping someone there would recognize this species. Within two days someone posted an answer that fits perfectly. It is a European import, the narcissus bulb fly, Merodon equestris. The only member of its genus in the U.S., its larvae are pests of daffodil and lily bulbs. The thorax color is highly variable, which is why it was difficult to find an exact match.

« Older entries

%d bloggers like this: