Sunday, January 20, 2019

Marching to the Lakeshore

Jumping Bush Crickets, fall, 2018

They’ve made it to the south shore of Lake Erie and are spreading along the lakeshore. It looks like they’re staging an invasion and trying to determine how to get across.

Handsome Trigs, fall 2018

Round-tipped Coneheads. Jumping Bush Crickets. Handsome Trigs. I’ve been documenting their northward movement for several years now. Will they find a way around Lake Erie to the Canadian shoreline?

Round-tipped Coneheads, fall 2018

I first met Round-tipped Coneheads in the Dayton area, and later discovered that some were already as far north as Geauga County. I then discovered they’re fairly common in Summit County and I began to focus on tracking them in counties farther north. Each year, I’d document more occurrences in NE Ohio parks and preserves including Medina, Lorain, Cuyahoga, Geauga, and Lake Counties. 

I hadn’t searched for them in Portage County southeast of Cleveland except for the Aurora area, but I found them this year at the Portage County Park District’s Breakneck Creek Preserve. 

Along the lakeshore, I’d already recorded them at Lake Erie Bluffs in eastern Lake County, North Kingsville Sand Barrens in the far northeastern tip of Ohio near the Pennsylvania border, and to the west at East Harbor State Park on the central Ohio lake shore’s Marblehead Peninsula. One would think they’d be elsewhere along the lake in addition.

I was invited to give a singing insect program last September at the Westlake Porter Library and decided after the program to see if there was any kind of field or meadow at nearby Huntington Reservation. I was already very close to this Cleveland Metroparks reservation, which is at the lake shore near the Cuyahoga/Lorain County line. It was a mild evening and still early, at least by my standards.

After listening to crickets and noticing Monarch butterflies mating in the dark, I thought I heard a buzzing in spite of the traffic on Lake Road…

..and sure enough  - there was yet another lakeshore-dwelling Round-tipped Conehead. 

                                       Round-tipped Conehead, Huntington Reservation

And there’s more. They’re also at Cleveland Metroparks’ Acacia Reservation, which is a former golf course across from Beachwood Mall and adjacent to both Legacy Village (a large retail complex) and the I-271 on-ramp at Cedar Road. 

How did they even GET there?

Then one of my music theory students heard a singing Round-tipped on campus in Cleveland’s University Circle.

Here’s my 2018 map of northbound Round-tipped Coneheads. 

 Canada, they’re coming! They just have to find a route. 

It might not be a land route, either. Jumping Bush Crickets have made it to Kelleys Island in Lake Erie. How did they get there? I think they took the ferry – in landscape saplings and shrubs. I’ve heard them singing in the outdoor garden section of a Home Depot parking lot not far from where I live, so why not? 

Humans have transported other insects – including singing insects – much farther. For example, the Roesel’s Katydid and the Drumming Katydid are both non-invasive European immigrants to our region’s species list. 

In addition to a possible ferry ride to the islands, Jumping Bush crickets are continuing to move northeast over land in Ohio. They’re well established in the Cleveland area now, though their presence is still spotty in the snow belt counties in the northeast corner of the state. But each year, they move farther into this snow-laden region and I’ve tracked their progress one highway at a time over the past 10 years. 

Although I’ve found them along I-90 from Cleveland all the way to downtown Erie, PA., there are still areas where their songs are missing from the singing insect chorus. 

They're doing well close to Lake Erie at Mentor Marsh in Lake County, where I recorded them at the Nature Center on 9-23-18. 


Although I’ve recorded them at Lake Erie Bluffs in eastern Lake County, I did not hear any in Lakeshore Reservation. None - but there were plenty of Handsome Trigs. It was quite unusual to hear one of these northbound cricket species without the other now, as it’s such a typical pairing these days (or nights, to be more accurate).

Lake Erie Bluffs to the west, and Lakeshore Reservation five miles to the northeast.
The recording was made at Lakeshore Reservation on 9-20-18.

Just south of Lakeshore Reservation near Rte. 20, though, I began to hear their songs again and I suspect they’ll make it to this park quite soon.

Before I continue to the last of these three northbound species, I’d like to tell you more about how range expansion sounds. Keep in mind that most of my survey work is done by ear, since these insects are small, protect themselves by staying hidden, and are often inaccessible.

But I can hear them – and I can hear that there are a lot of individuals singing once they become established in a new area.

For example, in 2017 I was looking for Snowy Tree Crickets in Portage County. This shouldn’t be so difficult. The song is distinctive and it’s not particularly soft. You know this one.

In areas like Portage and Summit Counties, however, the numbers of Jumping Bush Crickets are so large that there are times when I can’t hear any other crickets. The huge chorus drowns out everyone else except perhaps the noisy Common True Katydids. Jumping Bush Cricket choruses resound through the woods as well as residential areas. They also love edge habitats with…not surprisingly…lots of bushes. 

Snowy Tree Crickets like residential areas, shrubs, and vines as well, but they become almost inaudible when large numbers of Jumping Bush Crickets take over the stage with their wall of sound. In more residential areas where I was listening for Snowies from my car, I simply gave up because I couldn’t possibly hear them if they were present.

Jumping Bush Crickets were not an expected sound in the Cleveland area 15 -20 years ago, and it was exciting to hear a few individuals here and there when they first begin to move up here. They’re much more common in our parks now and increasingly common in the suburbs and even in the city. At what point with the wall of sound become the norm up here as well? 

Those beautiful little Handsome Trigs are continuing their northeast movement as well, as evidenced by their strong showing at Lake Shore Reservation. Currently in the Lake County Metroparks close to the lakeshore, their numbers still drop off in Ashtabula County. I’ve found just a few at Geneva State Park on Lake Erie, and last year I drove into the city of Ashtabula itself, listening in parks and neighborhoods. I finally found a small cluster of Handsome Trigs singing in shrubs next to a building in a warehouse area near the river.

I wondered yet again, how DID they get there?

It’s only been recently that Handsome Trigs' sparkling, crackling songs have become an addition to the expected smooth, silvery songs of the Say’s Trigs in the lakeshore counties. Although they’ve been abundant in Summit County, Handsome Trigs are now becoming a prominent and distinctive chorus in Lorain, Cuyahoga, and Lake Counties. Geauga County locations where I initially found just a few in a couple of buckthorns along a power line cut or a blackberry tangle near a trail now have steadily growing populations. The rapid increase in as little as a few years is both surprising and impressive!

And it’s easy to hear the population growth. For such tiny insects, they are surprisingly loud and their songs are quite distinctive. I find theirs to be a more prominent sound than the Say’s Trigs for whom I now have to listen more closely.

These shifting  ranges and changing ensembles aren’t just occurring in NE Ohio. Naturalist and singing insect specialist Carl Strang in the Chicago area has been studying crickets, katydids, and range expansion for many years, carefully documenting annual changes in range and updating maps for multiple species. His work shows very specifically where Round-tipped Coneheads, Jumping Bush Crickets, and Handsome Trigs are moving north in his region and by how much each year. You can read more about his work in his blog, Nature Inquiries. There's a search box on the left side of the page that allows you to search for the species you’re interested in reading about.

I’m already curious enough to consider a listening tour around the north shore of Lake Erie from Toledo across Canada east to Buffalo. I think they’ll need a land route unless they take a ferry. Unlike them, however, I’m going to have to finally get a passport…

If you'd like to read more about the species in this post, I've included links to the species accounts in my online field guide, Listening to Insects: NE Ohio's Crickets and Katydids. 

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