The Prairie Ecologist

I was featured on a podcast episode that came out today. I’ve enjoyed being a guest on quite a few podcasts, but I think this one might have produced the best synthesis of many of my thoughts on prairie management. If you’re interested in listening to it, check out the Wild Ag Podcast on your favorite app or click here.

A variety of habitat conditions across one swath of grassland at The Nature Conservancy’s Platte River Prairies in Nebraska back in 2023. Click on the photo if you want to see a bigger version.

Speaking of prairie management, as I was preparing a presentation on the topic last week, I came across an aerial photo I’d taken a couple years ago at our Platte River Prairies. The image does a great job of illustrating what habitat heterogeneity can look like across one management unit.

Variation in available habitat conditions (habitat heterogeneity) can be created by many factors. Some of those factors are unrelated to our actions as land managers. Topography, soil texture, and soil moisture, for example, all have big influences on what plant species can grow in a particular place. The same conditions can also drive the height and density of plants – high/dry/south facing slopes will have much shorter/sparser vegetation than low-lying/moist valleys, for example.

In the photo shown above, that influence can be seen in at least a couple ways. First, in the foreground of the photo, there are yellow stripes created by concentrations of blooming perennial sunflowers and goldenrods. Those plants are spread throughout the site, but are most lush and abundantly flowering in soils laid down by old river channels hundreds/thousands of years ago when this part of the prairie was part of the active Platte River.

Similarly, in the top part of the photo, you can see a broad slough that looks slightly darker than the surrounding vegetation. That slough is also an old river channel and has not only different soils, but is also lower in elevation and closer to groundwater, which helps determine both the plant species growing there and the height and vigor of those plants.

The management history of this site also plays a big role in the available habitat today. The top portion of the photo is unplowed (remnant) prairie, though it had some years of chronic overgrazing that decreased its plant diversity before The Nature Conservancy acquired it. We’ve replenished some of that lost plant diversity by overseeding missing species, but the plant community is still not what it was. On the other hand, it does have a very strong native sedge community and a pretty nice set of early season wildflowers that aren’t in the portion of prairie shown at the bottom of the photo.

That area shown in the lower portion of the photo was in row crops for years before being planted (not by us) back to grassland with a few wildflower species. Since then, it has increased in plant diversity, but no botanist would mistake it for an unplowed remnant prairie. It provides excellent habitat for many animal species, but has obvious differences from the adjacent remnant site.

Finally, the most dramatic variation in vegetation structure at the time this photo was taken was driven by recent management actions taken by Platte River Prairies manager Cody Miller and others. The entire prairie shown in the photo had cattle on it during the year of the photo (and in prior years). However, the grazing pressure across the site was very uneven, driven by prescribed burning.

In 2023, a spring fire was conducted in the area shown in the foreground, and a late July burn took place near the top right of the photo. When the 2023 growing season started, cattle focused most of their grazing in the recent spring burn, keeping that vegetation short and allowing plants elsewhere to grow tall. After the smaller August burn took place, cattle shifted some of their grazing there, reducing grazing pressure on the spring burn – which is partly why the sunflowers are blooming so abundantly. If you’re interested, you can read more about that summer fire and see more photos of it here and here.

Meanwhile, most of the remainder of the site had lots of tall vegetation and relatively thick thatch (accumulated dry vegetation from previous years’ growth) because it hadn’t been burned recently and had recovered from previous grazing bouts.

This mid-September photo shows part of the remnant prairie, with unburned grassland on the left and the summer burn on the right. The two areas provide very different habitat conditions for plants and animals, each of which is valuable.

As a whole, this management unit (roughly 500 acres, with more prairie across the creek to the north – out of frame to the right) provided a wide variety of habitat conditions for the plants and animals living in it back in 2023. Last year, in 2024, we burned yet another patch, which shifted grazing pressure to a new portion of the site and allowed the 2023 burned areas to start growing tall again. New management treatments in 2025 will continue to shift things around, while maintaining the same kind of habitat variety – just in different places.

If you missed it, I talked much more about habitat heterogeneity and why it’s important in this recent post. Our primary objective for the Platte River Prairies is to sustain high ecological resilience, which relies heavily upon species diversity (animals, plants, and more). We’re working under the assumption that providing a constantly-shifting mosaic of habitat types is the best way to support that species diversity.

There’s a lot of science that backs up that shifting mosaic assumption, but we try to test it whenever we can. Plant diversity has been very stable over the last 20 years or so on the sites I’m able to monitor closely. Habitat use by wildlife, including insects, is harder to quantify, but what we’ve seen has been positive. Birds species appear in different places each year, but all the species we’d expect to see always show up. Similarly, regal fritillary butterflies and other insect species seem to be doing well, but follow their favorite habitat conditions around the site. The plains pocket mouse – a species of concern in this part of the world – maintains surprisingly consistent populations, regardless of our management actions.

We’re always looking for researchers who’d like to help us look more closely at any aspect of the system – let me know if you’re interested! In the meantime, we’ll keep experimenting and learning the best we can.

One of the most unique, beautiful, noisy, and enigmatic insect groups in the prairie is the cicadas.

Hang on, is that good grammar? “Groups is” doesn’t sound right. But the subject isn’t “groups”, it’s “one”, and “one is” works. So that’s ok. But should it be “cicada” or “cicadas”? Is “the cicadas” a group? If so, I’ve got it right.

I guess it’s a great example of what grammar experts often say – “Sometimes, you just have to guess and hope you get it.” It’s nice that grammar experts are so flexible on these things.

Cicadas got a lot of attention last year because there were multiple

Plains dog day cicada (*Neotibicen auriferus*). I think.

Anyway. I really like cicadas. They’re distinctive and interesting to look at. Their calls are one of the sounds of summer in the prairie and the absence of that backing track would be very noticeable. I also love photographing them – when they’ll let me.

However, with all that said, I’m also frustrated at how little I know about prairie cicadas. Let’s start with identification. I’m pretty sure the cicada above and cicada below are the same species. They look pretty different from each other, but I have it on good authority that they’re both the plains dog day cicada.

You can find plains dog day cicadas every year (unlike the periodical cicadas that emerge only every 13 or 17 years). However, each of them probably lives 4-7 years belowground before coming aboveground and molting into an adult for the quick, noisy remainder of their life.

The tiny little cicada below is a small grass cicada, which narrows it down to a couple different species. It’s less than an inch in length and really easy to miss. My understanding is that there are two similar species that can be very difficult to distinguish based just on photos. If anyone can give a more specific identification on it, please let me know!

The greenish cicada below might be the same species as the tan ones above, or might be different. I think the most likely choices are Cicadettana calliope and Cicadettana kansa. I’m certainly not going to make any guesses, given what I’ve read about the difficulty in distinguishing between them! I’ll just admire both!

The charming little cicada shown below isn’t much bigger than the small grass cicadas, coming in at about 1 1/4 inches in length. It is apparently allopatric, which of course means that it is a species that doesn’t have any range overlap with close relatives.

I say “of course” like I didn’t just look that up. Most of you would have, too, so don’t be smug. I recognized the word as one I used to know, but it’s been a long time since my last evolutionary biology course. Also, it’s called the prairie cicada (Okanagana balli). The Latin is important here since there are several cicadas that are unsurprisingly called “the prairie cicada”.

I learned a little about Okanagana balli just the other day from a presentation by Katie Dana at the Illinois Association of Conservation Districts conference. She said that while it’s not one of the periodical cicadas (like the 17-year cicada, for example) it does tend to have big emergences (belowground nymphs maturing into aboveground adults) every 8-9 years.

As I understand it, though, you might see a few every year, so they’re not all on the same schedule. I could also have that wrong, but a quick Google search seems to back that up. I photographed several back in 2019 which likely means I won’t see many (or any) more until 2026 or 2027.

The most spectacular – in my opinion – of the grassland cicadas I’ve seen are the Megatibicen, which come in two species here in Nebraska. In the eastern part of the state, we get Megatibicen dorsatus and further west, we get the nearly identical Megatibicen tremulus. They’re both called “Bush Cicadas”, which is ok, I guess, though I don’t think they’re really tied to bushes or other woody plants. (Please don’t tie insects to bushes.)

As I understand it, experts can tell them apart by looking at the color of some of the wing veins and by their calls. Good for them. What I’m told is that when I see one at the Niobrara Valley Preserve, it’s probably M. tremulus, and when I see one at the Platte River Prairies – or further east – it’s probably M. dorsatus. I’ll stick with that for now.

This big bush cicada is probably *Megatibicen tremulus*, since it’s at the Niobrara Valley Preserve. Look at that gorgeous color!

Here’s a look at the face of *M. tremulus* at the Niobrara Valley Preserve. Can you count all five eyes?

Below are two photos of the eastern species of the bush cicadas – Megatibicen dorsatus. Probably. Both photos were taken at our family prairie south of Aurora, Nebraska. The first shows a mating pair with the male on the left and the female on the right. If you look closely, you can see the big plate below the legs of the male, which is absent on the female. Below that plate is the opening to its mostly-hollow abdomen that helps amplify the sound of its calls.

A near-mirror image of bush cicadas (*M. dorsatus*) except that the left is male and the right is female.

This is another *M. dorsatus* hanging out at our family prairie.

Here is a video I took of a male bush cicada calling several years ago. It was at the Niobrara Valley Preserve, so I’m assuming it is M. tremulus, but maybe an expert will recognize the song and confirm/refute that for me.

If the video isn’t functional for you, click on the title of this post to open it online so the link will work.

One of the questions I’ve had for a long time is whether cicadas have favorite food plants. Both adults and nymphs drink the liquids from plants and I’d assume there are differences in taste and nutrition between plant species. However, they don’t seem to care much about any differences that might exist.

As nymphs, cicadas attach themselves to plant roots and drink the xylem (liquid) that flows through them. Interestingly, the liquids in plants are split into xylem and phloem, and phloem is the one with a much higher sugar/protein content. For some reason, both adult and nymph cicadas feed on the less nutritious xylem. I don’t understand it, but they’ve made it work for a very long time, I guess.

Katie confirmed what I’d heard from others, which is that there’s no evidence that most/all cicadas have any preferences between plants. They are found on lots of different roots belowground and feed on a wide range of plants aboveground. I suppose there’s a lot of value in being a generalist. As an ecologist, though, I’m always looking for relationships between species and it’s a little disappointing to learn that cicadas will apparently just eat whatever they come across.

An empty exoskeleton of a cicada nymph after the adult emerged from it. You can still see the soil stuck to it because it emerged from underground right before the molt happened.

Here’s a brand new adult bush cicada at the Niobrara Valley Preserve with the exoskeleton it just emerged from in the background.

Cicadas, even the small ones, are relatively thick, armored creatures. They look like they’d be pretty well protected against predators. On the flip side, the noisy calls made by adult males draw attention from more than just female cicadas. I wonder how many females get eaten by predators compared to males?

Birds don’t seem to have any problem crunching through the hard shells of cicadas, and invertebrate predators have found work-arounds as well. I’ve been lucky to come across several examples of cicada predation, some of which I’ve been able to photograph.

If you know how big most crab spiders are, you’ll get a feel for how small this small grass cicada is.

This is one of the biggest robber flies I’ve ever seen, but it was still dwarfed by the big bulky Megatibicen tremulus (probably) it caught.

In both photos above, the predator had to find a chink the cicada’s armor in order to dispatch it. Both the spider and robber fly have similar methods for killing and feeding on prey – they inject chemicals that paralyze and “predigest” the insides of creatures and then suck out the liquefied remains. I don’t know how long it took the crab spider to subdue its cicada because it was over by the time I got there, but I got to watch the robber fly do it and it wasn’t quick. There was a lot of noise and struggling before the fly finally found a spot to work with.

A cicada impaled on a barbed wire fence by a loggerhead shrike at Konza Prairie Biological Station in Kansas.

While I’m no expert on cicada identification or behavior, I can at least appreciate cicadas aesthetically. There’s a lot to enjoy. Their calls and buzzing flight entertain my ears in the late summer and their stocky, shiny, bodies, large clear wings and big eyes make them a joy to see and photograph. When you’re out in the prairie next summer (especially the second half of the summer), be on the alert and you’ll likely find some of the species that hang around your area.

The Prairie Ecologist

Essays, photos, and discussion about prairie ecology, restoration, and management

Habitat Heterogeneity in One Photo

A Visual Celebration of Grassland Cicadas