Cicada on the Sidewalk: Not Quite Dead

Adult cicadas face a rough transition from nymph to adult and are always in danger of being eaten. However, quite a few cicadas do survive to mate and lay eggs. By late summer these survivors start to die of — what else can we call it? — old age.

So, a few days ago Aaron found our first half-dead Annual Cicada of the year. It just lay there on the sidewalk, legs folded up, as if it was asleep:

The dying Annual Cicada just lay there with its legs folded under its body.

When I picked it up, it started to buzz, vibrating my finger tips. But stopped after two seconds. Turning it over, we could see some body parts involved in making the buzzing sound (red arrow), plus the long, pointed beak it sometimes uses to suck sap from plants (blue arrow):

Underside of the Annual Cicada. The red arrow points to a protective covering (operculum) for the sound-producing organs. The blue arrow points to the tube (beak) that cicadas use to suck plant juice and occasionally jab a threatening animal -- or human.

Aaron and I decided to leave the dying cicada in peace. It was gone the next day, so it may have been found by a hungry bird or curious human.

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As noted in the caption, the part you see under the body is only protective — it doesn’t make the sound. The part that actually vibrates to make the buzz is up under the wings, and the muscles that cause it to vibrate are inside the body. If you’re interested in knowing more, there’s a detailed, illustrated description of cicada anatomy here. There’s a good technical description of how cicadas make sound here.

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Here’s an interesting observation about humans and cicadas. Although most years Annual Cicadas start singing in late June or early July, I’ve noticed that my Kids’ Cicada Hunt website doesn’t experience a big jump in visitation until 4 to 6 weeks later — when the cicadas start to die. I guess hearing cicadas doesn’t inspire much interest, but a cicada in the hand is worth a visit to cicada website or two. (My site is usually on the second or third page of results.) For comparison, my website statistics can tell when the first Cicada Killer Wasps emerge within a few days. The sight of a giant wasp inspires lots of folks to head for their computers, where they often find this picture of five-year-old Ethan holding dead Cicada Killers.

For a more complete analysis of when people visit my cicada website, check out this old CicadaBlog post.

Cicada FAIL: Growing Up Is Hard To Do

Maybe that title is a little harsh. Cicadas go through a lot as they convert from underground nymphs to adults flying through the treetops. Lots has to go right for it to happen, involving hormones and other complex biochemical activities on the inside and major changes to their bodies on the outside. And a lot of things can go wrong.

I’m not sure what happened here, but something cut short the life of this Annual Cicada, preserving it forever frozen in a transition from nymph to adult:

This nymph crawled out of the ground, climbed a wall, locked itself in place, and started to shed its skin -- but died before it could complete the transition to adult. The dead adult dried, darkened, and mummified into its current form.

I even feel a little guilty for displaying its dead body this way. Maybe we’ll go back and retrive it from the wall, and bury in our backyard pet cemetery. Or maybe we’ll let the ants do their job.

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To see what would have happened if everything had gone right, check out this series of photos on our Kids’ Cicada Hunt website.

This blog post discusses deformities and other things that can go wrong as cicadas transform from nymphs to adults.

Pokeweed Berries Ripening, Catbirds and Thrushes Coming Soon!

On the first Friday in September I noticed ripe Pokeweed berries in our backyard:

These are the first ripe Pokeweed berries I've seen this year, and they are in our backyard!

Soon there will be catbirds, thrushes, and many other birds with purple-stained beaks!

Gray Catbirds have spent the last five summers in backyards on our block. They stopped defending their breeding territory weeks ago, but I’ve seen a Catbird visit our Pokeweed once or twice since then. I think they keep track of berry bushes in the neighborhood so they can be the first to feast once the berries are ripe.

Swainson’s Thrushes breed up north, and then migrate south through our area starting late summer. Yesterday I saw two in the woods at nearby Columbus Park. Last September a Swainson’s Thrush stuck around our neighbor’s yard for two weeks feeding on her Pokeweed berries. A few weeks later a Hermit Thrush stopped by to eat its fill.

One nice thing about Pokeweed is that it keeps producing berries for many weeks, September through October. In this photo you can see ripe berries and a tiny flower stalk just starting, plus all stages of flowers and green berries in between:

The ripe Pokeweed berries are hidden among the leaves. A newly opening white flower stalk is to the left and above the berries, and in between stages are scattered elsewhere on the plant. By the way, the oval leaves are Pokeweed; the larger heart-shaped leaves are a type of Morning Glory.

So, this fall’s backyard catbird and thrush watch starts today, and then continues for almost two months!

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Note added Friday, September 4, at 2 p.m.: Early this morning we saw the first bird of the season feeding on our Pokeweed. It was an American Robin (which is a kind of thrush). Then, while monitoring birds at Columbus Park (less than a mile from our house), I saw about a dozen Swainson’s Thrushes and three Catbirds. Three of the Thrushes and one of the Catbirds were feeding on Pokeweed berries.

Note added Sunday, September 6, at 3 p.m.: We just saw three Swainson’s Thrushes in our Pokeweed patch! Aaron got the following for-the-record photo through our back window:

One of the three Swainson's Thrushes we saw on our backyard Pokeweed. Note the olive-brown back, lots of spots on a pale breast, and big buffy "spectacles" around its eyes. Photo by Aaron Gyllenhaal (shot through a sunlit back window).

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You can find more information about Pokeweed on Wikipedia. Cooked Pokeweed greens can be eaten, but raw Pokeweed can be poisonous to humans, as described on this National Institutes of Health web page.

The All About Birds website has more information about how Gray Catbirds, Swainson’s Thrushes, and Hermit Thrushes live their lives

Cardinal Eats Cicada: Two Interests Collide

Usually it’s kind of nice when two of our family’s interests intersect. But I’m still trying to decide how I feel about what happened this morning when a Cardinal caught and ate an Annual Cicada in our neighbor’s elm tree:

The Cardinal ate the cicada bit by bit. In this photo it's holding the cicada's wing and part of its body.

One problem we have when birds and bugs interact: Who do we root for? We love cicadas, and we love birds, and one gets eaten by the other! Usually we’re OK with birds eating cicadas, since adult cicadas die off in the fall anyway. But this year there aren’t as many cicadas around, so today’s encounter left me a little sad.

The Cardinal looks a little ratty in this photo, and it’s not just because the photo’s fuzzy. The Cardinals in our neighborhood are molting — shedding their old summer feathers and growing a new set for the winter. That’s why most Cardinals we see right now look bald. They’ve molted their old crests and the new ones are just getting started. Adult female and young Cardinals have similar greenish brown feathers, but I think the Cardinal in this photo is a female, because it has a bright red-orange bill and reddish on the wings.

Two other things about our neighborhood’s Cardinals right now: The males stopped singing a few days ago — they must be done defending the breeding territories they used this summer. Also, there are lots of young-of-the-year Cardinals around right now — sometimes the young ones chase the adults around our yard begging for food. I guess her babies were somewhere else, though, because this mommy Cardinal got to eat her cicada in peace.

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Note added Tuesday, September 8, at 8:30 a.m.: I just saw a House Sparrow carrying off a cicada! Counting its wings, the cicada was half the length of the sparrow’s body. The sparrow hid in some brush, perhaps hoping its flockmates would not notice its catch.

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For more information about Northern Cardinals, visit All About Birds. For more information about Annual Cicadas, try our Kids’ Cicada Hunt website.

Cicadas Are Singing, So It Finally Sounds Like Summer!

Despite the cool start to the day, Annual Cicadas have been singing almost continuously since the boys left for school. It finally sounds like summer — on September 1st!

So far I’ve heard three kinds of cicada songs: A slow-pulsing buzz, a faster-pulsing buzz, and a high-pitched, continuous whine. The best matches I’ve found for these songs are Scissor-grinder, Dog-day, & Linne’s Cicadas, respectively. Recordings of these cicadas (and many other insects) are online at the Songs of Insects website, here.

By the way, I’m glad someone finally gave common names to these cicadas! I especially like the name “Scissor-grinder Cicada.” Also, the folks who did the Songs of Insects website have a book with CD. We’ve got copies, and they are both beautiful and useful.

One more thing: I’ve still only seen two adult cicadas in our neighborhood this year: One sitting on the side of our neighbor’s house and another that a Robin was trying to catch — the Robin dropped it when it saw me coming. I wonder if adult cicada numbers will increase through September, or if the cicada nymphs still in the ground will just wait until next year.

Caterpillar in the Street: Tragedy or Transition?

During a break in this afternoon’s rains, I was walking along our street checking for migrant birds. Something caught the corner of my eye — I looked down and found this:

I found this three-inch sphinx moth caterpillar laying motionless on the street, under an American Elm tree. The head is on the left, the hind end (with its horn-like projection) on the right.

We find at least one of these caterpillars each summer, always on the street or sidewalk under an American Elm tree. The green color, overall shape, and especially the pointed projection on the tail convinced me that this must be some kind of hornworm — the caterpillar stage of a sphinx moth.

The caterpillar was motionless. I wondered if it had fallen 30 or 40 feet from the tree above and died. Just in case it was merely stunned, I brought it in our house and put it in a plastic box with some elm leaves. When Ethan and I checked it a few hours later, it was moving its head slowly, stiffly swinging back and forth, so it was still alive. Maybe we could save it!

Then we had a brainstorm. We knew that many hornworms dig into the ground and make a pupa — the transition stage from caterpillar to moth — without spinning a cocoon. And caterpillars often stiffen up before they split their skins, revealing the pupal stage within. Maybe this caterpillar had dropped to the ground on purpose, but had the bad luck to land on the street rather than soft soil. So we added some damp sand to the box, set the caterpillar on the sand, and waited.

Two hours later Ethan checked the box — the caterpillar had disappeared! However, a bit of digging revealed that it had merely dug its way into the sand and curled up into a tight C-shape. We left it alone, because pupating caterpillars can get all messed up if you bother them during this critical transition.

We’ll check again tomorrow and let you know what happened.

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Update: The caterpillar continued burrowing in the sand, digging all around the container and finally settling into a rounded cavity just below the surface. Then, after about a week, it died without making a pupa. It turned out to be a tragedy after all. We were very sad.

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Follow these links for more information about sphinx moths:

• Hornworms and “Hummingbird” Moths from Colorado State University Extension
• Elm Sphinx (Ceratomia amyntor). This web page shows the Elm Sphinx as having four horns — the one we found only has one. So, even though it seems to eat elm leaves, it must be a different species.
• Twin-spotted Sphinx (Smerinthus jamaicensis). The caterpillar shown on this page is a better match for ours, although not a perfect one. However, the text says the “larvae can show considerable variation.” According to the Colorado State University Extension site, some Twin-spotted Sphinx caterpillars eat elm leaves.

If our caterpillar pupates successfully we’ll have a sphinx moth to identify, which may be easier than identifying a caterpillar or pupa.

What Happened to this Year’s Cicadas?

I’m still wondering what happened to this year’s cicadas in our neighborhood. It’s a warm day in late August, yet it’s way too quiet here in south Oak Park. With all our big old trees to feed cicada nymphs, we usually have a pretty deafening chorus this time of day. However, this summer the cicada chorus has been pretty much of a bust through the hot part of the day, then a little louder at dusk. My family has found about a dozen shed cicada skins, but so far no live cicadas or dead adults have crossed our paths. What’s more, traffic on our Kids’ Cicada Hunt home page is way down — less than half of previous years.

On the other hand, I’ve seen maybe 10 times as many Cicada Killer Wasps as usual, mostly because I saw a couple of leks* at sand traps on the Columbus Park Golf Course. Also, traffic is high on my Cicada Killer web pages (here and here, and especially this photo of my then-five-year-old son’s hand). (The week-old blog post is already number 2 with a bullet on my list of all-time top posts.) It makes me wonder what all those mommy wasps are going to feed their babies!

So, how are the cicadas in you life doing? Same as usual, fewer — or are they blasting your ears out? Inquiring minds, like mine, want to know. Is anyone else worried what happened to their cicadas?

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*A Cicada Killer Wasp lek is an area where the Cicada Killers emerge and congregate, and the males fight for the right to mate with females of their species. (See here and here.)

Will Birds Be Migrating to Our Block Party?

The boys and I just checked the weather radar to see if the rain will be ending soon — and to see if birds are migrating south towards our “No Child Left Inside” block party. If you look at this weather radar image from the Chicago Tribune‘s website, you’ll see the answer should be yes on both counts:

The green-and-yellow streaks and blobs around and southeast of Chicago are rainstorms. The green circles north and west of Illinois are night-migrating birds taking off and flying south. The animated version of this image showed storms (and migrating birds) moving to the southeast, through Chicago.

Why are birds on the move? Because winds blowing from the north help migrating birds make their southward journeys. Here’s a wind map to show you what we mean:

This map shows wind patterns at about the same time as the radar image, above. By morning we may have five to ten mile-per-hour north winds blowing through our neighborhood, just west of Chicago.

Overnight north winds may bring smaller birds like warblers, flycatchers, and thrushes to our block party. The night-migrating birds will land near sunrise and then spend the morning searching for food. If north winds continue through the day we may see some hawks migrating overhead.

Of course, north winds bring cool air, so temperatures at tomorrow’s block party may only reach the low 70s. (The neighborhood kids won’t be running under the sprinklers like they have some years.) However, our 7:30 a.m. nature walk may turn up some interesting birds, and we’ll keep our eyes and ears open for fall migrants throughout the day.

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To learn more:

You can study bird migration using radar images from WeatherUnderground (the source of the Tribune’s images) and the National Weather Service radar website.

The WoodCreeper.com blog tracks bird migration of New Jersey (and other parts of the United States) using weather radar.

To learn more about using weather radar to track bird movements, try the Badbirdz – Reloaded blog, which includes a primer on using weather radar to track bird migration. For deeper explanations of bird migration and radar, try the New Jersey Audubon website.

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Our Husked Buckeyes Are Ripe!

A week ago I cut through a Buckeye husk and found the full-sized nuts were still white — not the rich brown Buckeye color that’s so beautiful. (You can see the unripe nuts here.)

Well, I set the unripe nuts and husk on a top shelf in our kitchen, out of reach of cats and squirrels. A week later, this is what I found:

Last week the unripe Buckeye nuts were white -- today they were brown and shiny!

The nuts had turned brown and shiny! However, they had also shrunken and wrinkled just a bit. The husk had shriveled and split, revealing a third nut hidden inside.

I’ve got eight or ten more Buckeye husks set aside. I was thinking of cutting them open at the block party this Saturday and making Buckeye crafts (see ideas here). But there are two things that worry me: Some kids on our block have nut allergies — would those extend to Buckeyes? (Others have pondered this question.) Also, many references say fresh Buckeyes are poisonous to fish and other living things (for instance, here). So, maybe Buckeye husking will be a demonstration and not an activity.

Sometimes I wonder how I survived childhood.

Update added October 30, 2009: Buckeyes trees are similar to Horse Chestnut trees. Here’s a blog post from Scotland about collecting conkers, which look like buckeyes but come from Horse Chestnut trees: http://creativestarlearning.blogspot.com/2009/10/conkers-part-1.html

Added November 10, 2009: Conkers, Part 2, is all about games children can play just as well with Buckeyes as with Horse Chestnuts: http://creativestarlearning.blogspot.com/2009/10/conkers-part-2.html

Was that an American Kestrel across the Street?

Yesterday morning I heard a “killy killy killy killy killy” sound coming from the treetops across the street. It sounded like this: (play sound file). My first guess was American Kestrel. My second guess was a local Blue Jay who does a good impression of a Kestrel.

I walked down the sidewalk to a break in the trees, so I could see the top of a neighbor’s spruce where Kestrels have perched before. The boys followed with their cameras, and this is what we saw:

As soon as we saw the bird at the top of the spruce tree, we could tell it was a Kestrel and not a Blue Jay. Kestrels are small falcons, and this bird had the classic falcon shape in silhouette. Photo by Aaron Gyllenhaal.

A closer look showed it was a male Kestrel, because the breast was more spotted that streaked. (There are also color differences not visible in this photo.) Photo by Aaron Gyllenhaal.

So, mystery solved! One other thing: We had very few small birds at our feeder for the next hour or two.

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Check these links for more information about American Kestrels:

• American Kestrel on Cornell’s All About Birds website
• American Kestrel on the United States Geological Survey website (the source of the sound file)