Wednesday, September 5, 2012

Insect sings like a frog

An oblong-winged katydid, Amblycorypha oblongifolia, shouts his song to the night.

I was tasked with leading a nocturnal foray last Friday night in Ohio's northeasternmost county, Ashtabula. Insects, of course, were a dominant part of the evening's festivities. Many in the group were birders, and I always enjoy sharing the songs of insects with birdwatchers who may not be in tune with the Orthopteran symphony.

Most, or at least many, birders strive to improve their ability to recognize bird calls. It isn't always easy, depending upon the amount of tin in your ear, but the dividends of improved bird call recognition are enormous - you'll find WAY more birds. Come late summer, though, the level of songbird song drops way off. What's an aspiring song-learner to do, short of pulling out the tapes for practice?

Turn your ear to the bugs! The Orthopterans - crickets, coneheads, katydids and the like - start to come on strong about the same time that bird song falls off the acoustical cliff. The various fiddles of the "singing insects" can also be learned, just as can bird calls. Some are easy and in your face; other species have much subtler tunes, or sound a lot like other species. It's fun and rewarding to learn to sort them out, and doing so will make one far more adept at mastering bird song.

We move in much closer to the oblong-winged katydid in the preceding shot. I had heard him from some distance away, singing back in a scruffy woodland opening. Once pointed out to the group, everyone quickly keyed in on the animal's song. It is a rather loud scratchy ree-DIP that sounds like a frog. Hear it for yourself, RIGHT HERE.

Experience has taught me that this species, and some of the other bush katydids, "tee up" when singing, just as many songbirds do. You just can't see them, because its dark. But by moving furtively, following the sound, and shining a flashlight well out in front, you can sometimes spot the six-legged singer from afar. That's what we did in this case, and the cooperative if not somewhat perplexed bug sat tight atop his twig and allowed many of the group to close in for a good look.

The nocturnal world of sound is a fascinating subject, and is all around us. Many of the singing insects are urbanites, and liable to calling in your backyard right now. As I write this, from my home in the big city, I can hear fall field cricket, Japanese burrowing cricket (blog to come), two-spotted tree cricket, greater and lesser anglewing katydids, and more. They are creating the night's sound track; a staple feature of the ambiance of late summer and fall evenings.

A landmark book that brought the conspicuous yet hidden world of singing insects into the public eye is the Songs of Insects, by Lang Elliott and Wil Hershberger. This is one of the finest natural history works in modern times, and greatly aids one's ability to easily learn many of these insects. The photography is stunning, and it comes with a CD of sounds. Get it RIGHT HERE.

2 comments:

Sharkbytes said...

How do you tell A. oblongifolia from A. parvipennis?

Jim McCormac said...

Good question, S-bytes. I reckon their songs are different, but I have no firsthand experience with that species. It doesn't make it as far east as Ohio.