Backyard Nature: Insects produce the backyard symphony of August

by Marjorie Rachlin

It’s 8 a.m., and I’m sitting on the back porch, looking out at the garden. No birds, no bees yet. It’s August and nature is slowing down.

Suddenly a persistent buzz comes from the oak trees. In August and September, the sound filling the air is not bird song. This is when cicadas, katydids, crickets and grasshoppers fill our backyards with sound.

I listen, sipping my coffee. The buzz comes in waves, swelling louder, tapering off, pausing abruptly. One cicada species pauses after five seconds and another species keeps going for 15 seconds. After a couple of minutes, the sound shuts down, sometimes for hours.

The cicadas sing more when it is hot and muggy. As the temperature rises, the song speeds up with this kind of insects. An expert who studied the snowy tree cricket found that if you counted the number of chirps in 13 seconds and added 40, you would have a good approximation of the temperature!

At night, it’s a chorus

After dark, the insect chorus really gets deafening – katydids, cicadas, tree crickets, maybe field crickets, grasshoppers. It’s hard to figure out what kind of insect you are hearing and I recommend SongsofInsects.com. It has great audio and lots of info, which I am referring to in this article. The site has also given us permission to reproduce a few of their insect photos.

Cicada songs are often described as a “pulsating buzz” or a “drone.” They and the katydids have a similar mechanism for making sound. They rub their wings against a special organ on their abdomen. They are busy day and night.

After dark, I find that the katydids song often dominates the evening. It is a “series of tic, tic, tic accompanied with buzzes… somewhat like a shaker full of rice or a ratcheting sprinkler,” according to SongsofInsects.com.

You’ll hear crickets, too. We recognize them because of the crickets that come into our basements in the fall. There are 115 species of crickets in North America, and each species has its own particular song, but all crickets have a melodic quality.

As of mid-August, I am hearing a loud, continuous musical trill in the backyard at night – probably a group of tree crickets. There may be field crickets and ground crickets that I can’t distinguish.

Grasshoppers are the fourth part of the chorus. There are many more grasshoppers out there than we usually see because they are hiding in the meadows. Grasshoppers’ legs go up and down and scrape against the edge of the wings, making a high-pitched trill or sometimes a snapping sound.

Listening for these sounds brings surprises. Go out in the yard at night and tune in. You will be amazed at the variety of pitch, speed and beat.

Why are they singing?

The males are trying to attract a mate. It’s serious sex – they are in a hurry to reproduce before cold weather comes, when most die. Cicadas for example, often amplify their sound by gathering in groups to attract females. If the male succeeds, he gives the female a sperm packet, and she will lay 200 to 400 eggs in tiny slits in the bark or stems of trees.

The “nymph,” which hatches in about six weeks, drops to the ground and buries itself. It eats juices from roots for as long as four years, then emerges, crawls up a tree trunk, and a winged adult emerges.

Right now we are hearing annual cicadas. These are not the cicadas that emerge in astounding numbers every 17 years. Those 17-year cicadas are often mistakenly called “locusts,” and people identify them with the scourges of locusts in the Bible. Not so. Those Biblical “locusts” are grasshoppers, eating everything in their path. They are still a problem in the Middle East.

Katydid and crickets have a special mating trick. During mating the male transfers a bubble-like protein pack to the female, which she will eat and will help her develop her eggs.

What’s chirping in our yards and parks?

We’re invited to participate in a citizen science project on Friday, August 26th.

Participants in the 2016 DC/Baltimore Cricket Crawl are asked to go outside after dark and listen for one minute for the sounds of six insect species, then immediately report the results via phone, email, tweet or text message. Here’s the how-to.

Visit discoverlife.org/cricket/DC for more information, including good photos and audio of the six insects targeted by the census. Or contact Cathy Stragar at the local Audubon Naturalist Society, 301-652-9188 or dc_cricket_crawl@yahoo.com.

Insects at center stage

Just like the choristers, August and September are crucial reproductive months for many of the insects in our area – butterflies, moths, beetles, bumble bees. The bumble bees will soon produce a new queen before they die, and they are busy preparing. She will live over the winter and start a new colony next spring.

The honey bees will spend winter in the hive. They do not work if the temperature goes below 50 degrees, so they are busy now laying in a good supply of honey and pollen.

Match.com for swallowtails

Only a few butterflies live over the winter in hibernation. Most die. Right now you can see yellow tiger swallowtails and black tiger swallowtails flitting carefree, over our garden flowers. Actually, they’ve got mating on their minds – often you will see two of them in the air, circling each other in a slow dance for several minutes, deciding whether this match has possibilities. Usually I see them break apart – they didn’t fit.

After she mates, the female swallowtail will lay eggs, usually on oak leaves, and she will die. Her offspring caterpillars will gorge, then spin cocoons that will carry the species over the winter.

Our birds are preparing to migrate but that’s for another article. I’m going to spend a lot of time this month in the backyard, listening and watching for the changes August brings.