Showy Insects at the Lights

by Carl Strang

The rain stopped for a while on the night of the Hills of Gold bioblitz in Johnson County, Indiana. I set my single ultraviolet light on a hilltop, following a muddy climb up a steep logging trail. My light faced a different downslope than the nearby, more elaborate multi-light array of the Purdue beetle team led by Jeff Holland. My aim was moths, and a satisfying variety came to the sheet lit by my UV tube. Today I will share photos of some of the more spectacular insects we found.

The biggest was this tulip-tree silkmoth which came to one of the Purdue lights.

The biggest was this tulip-tree silkmoth which came to one of the Purdue lights.

Two of these beautiful, strikingly marked green moths came to my station. Their English name is appropriate: green marvel.

Two of these beautiful, strikingly marked green moths came to my station. Their English name is appropriate: green marvel.

Another eye-catcher was this one, curiously named The Hebrew.

Another eye-catcher was this one, curiously named The Hebrew.

The unadorned carpet was one of the moths commonly encountered during the day. One came to the sheet as well.

The unadorned carpet was one of the moths commonly encountered during the day. One came to the sheet as well.

The splendid palpita has attractive patches of pinkish brown on all four wings.

The splendid palpita has attractive patches of pinkish brown on all four wings.

According to its page in the BugGuide website, the brown-spotted zale actually is a species complex containing several species distinguishable only by dissection.

According to its page in the BugGuide website, the brown-spotted zale actually is a species complex containing several species distinguishable only by dissection.

That last point may well be true of many of the moths of the North American forests. This is where I need to compromise my reluctance to collect insects. There are enough instances of sibling species or cryptic species among the moths that voucher specimens are necessary. Given the growth of DNA analysis, two specimens per species per site may be the standard I will need to follow, so that one or part of one could be sacrificed to future chemical analysis. From an ecological as well as an evolutionary standpoint, the existence of these cryptic species is an interesting problem that needs to be sorted out.

Of course, many insects other than moths came to my sheet. This fish fly appears to be Chauliodes pectinicornis.

Of course, many insects other than moths came to my sheet. This fish fly appears to be Chauliodes pectinicornis.

Several fiery searchers prowled my sheet and its vicinity. These large beetles are predators that frequently attack caterpillars.

Several fiery searchers prowled my sheet and its vicinity. These large beetles are predators that frequently attack caterpillars.

Next time I will elaborate on other moths that were drawn to the lights. These illustrate a number of additional points about forest moth populations.

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Hills of Gold

by Carl Strang

This year’s chapter in the bioblitz series organized by the Indiana Academy of Science was called Hills of Gold. It was on a beautiful site being assembled by the Central Indiana Land Trust, and when complete will occupy around 2 square miles in Johnson County, south of Indianapolis.

The event took place on an intermittently rainy day, as illustrated by this less than sharp image of a representative bit of forest and one of the old logging trails we used to get around the site.

The event took place on an intermittently rainy day, as illustrated by this less than sharp image of a representative bit of forest and one of the old logging trails we used to get around the site.

Usually my role in these bioblitzes is to survey singing insects, but this was too early in the season for a sufficient number of species to justify my participating. I decided to reconnect with my experience studying forest Lepidoptera ecology in the 1980’s, and took on moths as well. As I walked the forest during the day, I found many beautiful plants and animals outside my target groups that gave joy.

Green dragons always make me smile, and I ran across a magnificent cluster of them along one of the streams.

Green dragons always make me smile, and I ran across a magnificent cluster of them along one of the streams.

And who can say “no” to fire pinks? Hummingbirds sure don’t.

And who can say “no” to fire pinks? Hummingbirds sure don’t.

Violet wood sorrel is a plant I haven’t encountered very often.

Violet wood sorrel is a plant I haven’t encountered very often.

There also were insects to note outside my target groups.

This Bombus impatiens queen still had not found a nest site, and was prospecting the forest floor.

This Bombus impatiens queen still had not found a nest site, and was prospecting the forest floor.

I interrupted this female scorpionfly’s feed on an emptied caterpillar skin.

I interrupted this female scorpionfly’s feed on an emptied caterpillar skin.

Speaking of caterpillars, the first target species I found was this eastern tent caterpillar:

They already had reached the final instar and were starting to pupate.

They already had reached the final instar and were starting to pupate.

I collected only four moth species during the day. All were fairly common.

This was one of them, which I identify as the unadorned carpet, a member of the inchworm family.

This was one of them, which I identify as the unadorned carpet, a member of the inchworm family.

Many more moths came to my ultraviolet light setup that night. Stay tuned for that episode.

For the record, there was one singing insect. This was my first encounter with a wood cricket. I heard them scattered thinly all through the forest, but never succeeded in seeing one. They probably were northern wood crickets (Gryllus vernalis), but might have been southern wood crickets (G. fultoni). I made a couple good sound recordings, which I hope will allow me to make the determination.

One of them was singing from this patch of leaf litter.

One of them was singing from this patch of leaf litter.

More on that later, after I have analyzed the recordings.

Heart of Migration

by Carl Strang

We now are in the tail end of the spring migration season for birds. This was a very good spring for birds at Mayslake Forest Preserve.

Several blackburnian warblers stop at Mayslake every spring.

Several blackburnian warblers stop at Mayslake every spring.

Until I got into the study of singing insects, I thought of the rising high note at the end of the blackburnian’s song as my annual hearing test. I still can hear that note fine, but some of the insect songs get fainter each year. Others I can’t hear at all.

We also consistently see and hear rose-breasted grosbeaks at Mayslake in spring, but so far none have nested there.

We also consistently see and hear rose-breasted grosbeaks at Mayslake in spring, but so far none have nested there.

Blue-headed vireos trickle through in spring, but will nest farther north.

Blue-headed vireos trickle through in spring, but will nest farther north.

At least 3 pairs of indigo buntings will stay to nest at Mayslake.

At least 3 pairs of indigo buntings will stay to nest at Mayslake.

This clay-colored sparrow stopped by on a cloudy day. This is only the fourth or fifth member of its species I have observed at Mayslake. They nest in the county, but not there.

This clay-colored sparrow stopped by on a cloudy day. This is only the fourth or fifth member of its species I have observed at Mayslake. They nest in the county, but not there.

Though the fanned tail is the main part of the American redstart visible in this photo, that bit is worth sharing. This bird’s specialty is flashing its wings and tail to flush insect prey into flight, so that it acrobatically can chase them down.

Though the fanned tail is the main part of the American redstart visible in this photo, that bit is worth sharing. This bird’s specialty is flashing its wings and tail to flush insect prey into flight, so that it acrobatically can chase them down.

The bay-breasted warbler tends to peak in the latter part of the migration season. Its song is like a weakened version of the black-and-white warbler’s “wee-see-wee-see-wee-see.”

The bay-breasted warbler tends to peak in the latter part of the migration season. Its song is like a weakened version of the black-and-white warbler’s “wee-see-wee-see-wee-see.”

This will be my last spring migration at Mayslake, but I anticipate equal or greater diversity at St. James Farm next year.

 

Release the Toad!

by Carl Strang

The mansion at Mayslake Forest Preserve is a big building with a big perimeter. Its window wells can be pitfalls for small animals, for instance the skunk rescued by Nikki Dahlin a while back. Its many entrances offer opportunities for small animals to find their way in, as I told a few years ago in the story of the Phantom of the Mansion. Today brings another such story, this one bringing Nikki together with an American toad that turned up in the basement in the middle of winter. Nikki set it up in a small terrarium, where the Mayslake staff joined Nikki in caring for the little amphibian, feeding it worms and domestic crickets.

The weather warmed up to the point where Toad could be returned to the out-of-doors. Everyone hoped he would stay out of mischief this time (yes, that was a Wind in the Willows reference). We carried him down to the stream corridor marsh.

Nikki turned the terrarium on its side.

Nikki turned the terrarium on its side.

Toad waited a while before hopping out onto the moss.

Toad waited a while before hopping out onto the moss.

We were impressed when Toad immediately slid his or her hind legs under the moss and wriggled down in until he or she was mostly covered.

We were impressed when Toad immediately slid his or her hind legs under the moss and wriggled down in until he or she was mostly covered.

With this reminder that Toad had all the instinctive tools needed to carry on from there, we were content to say goodbye.

Mayslake Bugs

by Carl Strang

The warming weather has produced the first wave of insects at Mayslake Forest Preserve. These early-season adults overwintered in that form or in the stage just prior, or in some cases, migrated from the South.

The Carolina saddlebags is one such likely migrant.

The Carolina saddlebags is one such likely migrant.

This individual gave me a rare opportunity to photograph it in such a way as to show off its diagnostic purple forehead. The slender legs have the strength to hold the dragonfly to its perch.

Though I think of the eastern tailed-blue as a late-summer butterfly, that is the second generation of the year. Here is one of the early-season firsters.

Though I think of the eastern tailed-blue as a late-summer butterfly, that is the second generation of the year. Here is one of the early-season firsters.

Wild indigo dusky wings frequently may be encountered at Mayslake early in the season.

Wild indigo dusky wings frequently may be encountered at Mayslake early in the season.

The preserve harbors two host plants for the caterpillars: white wild indigo, a desired native prairie species, and the unwanted crown vetch, an introduced invasive.

Mayslake Birds

by Carl Strang

Bird action at Mayslake Forest Preserve has sped up to the point of being hard to follow. Migrants have been stopping by in good numbers.

Baltimore orioles are scattered through all the woodlands. Some will stay and nest.

Baltimore orioles are scattered through all the woodlands. Some will stay and nest.

Warbling vireos are another recent arrival.

Warbling vireos are another recent arrival.

Savannah sparrows haven’t nested at Mayslake yet, but one day last week the meadows and prairies were full of them.

Savannah sparrows haven’t nested at Mayslake yet, but one day last week the meadows and prairies were full of them.

I know this is a broken-record theme for me (for those of you old enough to know what that expression means), but note how in the face-on view all those head stripes converge on the bill, accentuating it for rival intimidation (maybe). I’m reminded of Maori facial tattoos.

I know this is a broken-record theme for me (for those of you old enough to know what that expression means), but note how in the face-on view all those head stripes converge on the bill, accentuating it for rival intimidation (maybe). I’m reminded of Maori facial tattoos.

This Canada goose brood appeared on Mays’ Lake.

This Canada goose brood appeared on Mays’ Lake.

On the same day, the nest in the nearby stream corridor marsh was empty, with open eggshells, almost certainly that brood’s origin.

On the same day, the nest in the nearby stream corridor marsh was empty, with open eggshells, almost certainly that brood’s origin.

The other nest, in the parking lot marsh, has been abandoned. Three unhatched eggs are visible. The highest water levels in recent rains may have reached their undersides.

The Cooper’s hawk nest is under incubation just off the preserve in a neighbor’s yard.

The Cooper’s hawk nest is under incubation just off the preserve in a neighbor’s yard.

The nest was found by Vicky S., a former student of mine who went on to mentor with some of the area’s top birders and should be regarded as one of their number at this point. There’s some satisfaction to be had in being surpassed by one’s student. She pointed out that this is an unconventional structure, the hawks having added a layer of sticks to the top of a squirrel nest.

Phenology First Take

by Carl Strang

One of the best ways of assessing how a given year compares with previous ones is by looking at first flowering dates. With April now complete, I can review those for Mayslake Forest Preserve. On the whole, this April can be regarded as slightly early, thanks to significant early warm days melting the snow and warming the soil.

Dutchman’s breeches bloomed abundantly at Mayslake this year.

Dutchman’s breeches bloomed abundantly at Mayslake this year.

Comparing median first flower dates in April places 2015 6 days earlier than 2014 (11 species), 9 days earlier than 2013 (20 species), 6 days earlier than 2011 (21 species), and 3 days earlier than 2009 (17 species). This April was 9 days later than 2010, and a substantial 25 days later than the anomalous warm year of 2012.

Most of these differences are not very large, and the expectation is that they will gradually diminish over the coming months.

Singing Insect Season Opens

by Carl Strang

Last Wednesday the long silent drought of insect song was broken as I heard the first displaying green-striped grasshopper of the year, at Churchill Woods Forest Preserve. Then, on Friday, I found many of them buzzing in the south stream corridor prairie at Mayslake Forest Preserve.

This male rested after a relatively long flight.

This male rested after a relatively long flight.

If you want to listen for the crackling-wing songs of these grasshoppers, I posted a recording HERE not too long ago. They show up in all kinds of grassy areas.

I continue to be puzzled by green-striped grasshoppers. Sometimes their buzzing display flights are long, and fairly easy to see. Most of the time, though, I hear briefer buzzes and do not see any movement. Either I am not correctly locating the displaying insect, or they can buzz within the vegetation without flying. I don’t think these simply are very short display flights, because the grasses in that prairie are matted nearly to the ground. On the other hand, the males are well camouflaged, their wings are not colored like those of many of their relatives. On the longer flights they are most visible at the beginning and end, practically disappearing in the fast major portion.

Mayslake Vertebrate Action

by Carl Strang

The season’s progress can be measured in many ways. One is through vertebrate activities.

A fox squirrel feeding on flowers

A fox squirrel feeding on flowers

Song sparrows, among other birds, have been singing like crazy.

Song sparrows, among other birds, have been singing like crazy.

Migration is accelerating. This unusually pale savannah sparrow stopped by Mayslake Forest Preserve a couple weeks ago.

Migration is accelerating. This unusually pale savannah sparrow stopped by Mayslake Forest Preserve a couple weeks ago.

Pied-billed grebes have been regulars on Mays’ Lake.

Pied-billed grebes have been regulars on Mays’ Lake.

And the Cooper’s hawks are happy to exploit the stopovers of migrants who don’t know the territory.

And the Cooper’s hawks are happy to exploit the stopovers of migrants who don’t know the territory.

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