Playing Catch-Up 2

by Carl Strang

Odonata continue to show well at Mayslake Forest Preserve. Today’s photo gallery features some recent sightings.

This male spreadwing clearly was not a slender spreadwing, which species has dominated the spreadwing damselfly fauna at the preserve this year. I generally photograph these from the side and above, as I haven’t yet internalized their distinguishing features.

This male spreadwing clearly was not a slender spreadwing, which species has dominated the spreadwing damselfly fauna at the preserve this year. I generally photograph these from the side and above, as I haven’t yet internalized their distinguishing features.

The abdomen tip tells the tale, both with the triangular black intrusion in segment 8, and in the shape of the terminal appendages, which demonstrate why this species has been named the lyre-tipped spreadwing.

The abdomen tip tells the tale, both with the triangular black intrusion in segment 8, and in the shape of the terminal appendages, which demonstrate why this species has been named the lyre-tipped spreadwing.

This is only the second or third time I have encountered that species at Mayslake. A dragonfly which likewise has made few appearances is the Halloween pennant.

This teneral individual was perched near Mays’ Lake, from which it probably emerged.

This teneral individual was perched near Mays’ Lake, from which it probably emerged.

The following dragonflies are regulars, but no less beautiful for that.

Common green darner

Common green darner

Jade clubtails have been resting on algal mats in the lakes.

Jade clubtails have been resting on algal mats in the lakes.

One of the fiercest dragonflies for its size, a common pondhawk.

One of the fiercest dragonflies for its size, a common pondhawk.

Common whitetails are easy photographic targets, as they often rest on the ground.

Common whitetails are easy photographic targets, as they often rest on the ground.

Insect Catch-Up

by Carl Strang

I consider photos to be an indispensible part of this blog. Blogs are based on writing, but in a visual medium like a computer screen, I believe images are needed as well. I try to get photos of everything new I encounter in the field, and edit and copy selected ones into a file I keep for the blog. They then are the basis for new posts. Sometimes there are orphan photos, ones which by themselves may not be enough for an entire entry. Today I want to clear out three such photos of insects. The first goes back to mid-June.

Unicorn clubtail on May’s Lake

I had been seeing a few jade clubtails at Mayslake Forest Preserve, perched on shore or occasionally on floating algae, but then on June 16 there was an odd-looking individual that clearly was a new species for the preserve list. The photo made clear that this was a unicorn clubtail, a species in the same genus as the jade clubtail, common in some places but not, in my experience at least, in DuPage County.

Reversed haploa, a member of the tiger moth family

This was a big year for reversed haploas. Usually I see 5 or so in a season, but I saw dozens at Mayslake in the first half of July.

Bombus pensylvanicus. I think.

There are two species of bumblebees in northern Illinois that are so similar I cannot distinguish them confidently. From what I have seen in internet sources, I am not alone in this. Both have large areas of black on the thorax and large areas of yellow on the abdomen. There are variations in “fur” color on the head and posterior thorax that bring enough overlap into the picture to confound the identification of individuals. As far as I can tell, it comes down to the color of the basal abdominal segments. Less black and more yellow indicates pensylvanicus, more black and less yellow indicates Bombus auricomus. In my limited experience, though, there appears to be another possible indicator. B. auricomus seem to be brighter, the yellow and black so sharp as to really stand out, while the colors are duller in pensylvanicus.

Here is an auricomus from an earlier year

If any readers can lend insight on this, I would appreciate a comment to that affect.

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.

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.

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.

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.

Mayslake Odonata Update

by Carl Strang

The weather has been rainy, gloomy and cool on many recent days, but when the sun appeared so did the insects. At Mayslake Forest Preserve I have been able to add new species and observations that provide a foundation for future study. Eastern forktail damselflies already have been busy laying eggs in May’s Lake.

Eastern forktails laying eggs b

Meanwhile, other damselflies are emerging. The next two photos are, I believe, of common spreadwings, a male

Common spreadwing b

and a female.

Common spreadwing female 3b

Having newly emerged, they are holding their wings together more than usual. Another spreadwing species is the slender spreadwing.

Slender spreadwing 1b

Note the contrasting pale veins of the wingtips. Another, blurry photo established that the abdomen has the characteristic length, twice that of the wings. I have seen orange bluets at both of the preserve’s lakes.

Orange bluet b

Familiar bluets also have begun to appear.

Familiar bluet b

The year’s first blue-fronted dancer was a female.

Blue-fronted dancer female b

Its abdomen is dark, including the sides of the tip, and has only a very narrow pale line down the top. Shifting now to dragonflies, I’ll start with a 12-spotted skimmer that began patrolling the stream corridor marsh in June. I expect the species to be common there. This one I photographed elsewhere in 2004.

12-spotted skimmer b

Blue dashers have been active out in the fields, and soon will be appearing at lakes and marshes.

Blue dasher female 1b

A jade clubtail has staked out a piece of the May’s Lake shore.

Jade clubtail b

Cruising farther out are the prince baskettails. Here is a UFO-ish shot of one.

Prince baskettail UFO b

And here is a common baskettail  showing the basal wingspots that are visible on some, but not all individuals.

Common baskettail spot b

A final, cautionary photo:

Eastern forktail new female b

This is not an orange bluet, but a newly emerged female eastern forktail. Note the absence of the orange at the abdomen tip plus the expanded orange area at the base of the abdomen.

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