Photo of the Week – The Prairie Ecologist

Grasshoppers are a major ecological force in prairies.  They’re also fascinating creatures when you really look at them closely.

This grasshopper was photographed last week on a milkweed plant that had turned its autumn yellow color. It's nice that this one can keep grinning, in spite of the negative reputation grasshoppers have with many people... Lincoln Creek Prairie - Aurora, Nebraska.

To many gardeners, farmers, and ranchers, grasshoppers are seen as an adversary.  Unfortunately, that categorization ignores a much more complex story.  First of all, only a very small subset of grasshopper species do any significant damage to crops or garden plants.  Most live their own lives quite happily without any help or interaction with humans, thank you very much. 

Some grasshoppers are generalist feeders, but others feed only on particular species or groups of plants.  There are grasshopper species that forage high in the prairie canopy and others who feed along the ground – some by chopping down plants like little long-legged lumberjacks.  In addition, most grasshoppers feed largely on actively growing vegetation, but others eat what’s fallen to the ground (including some of what the lumberjack hoppers knock down).  Grasshoppers use sensitive organs at the tips of their antennae to determine whether a particular plant is something they want to eat or not.

In the above photo, you can see some of the anatomy that makes grasshoppers the fascinating creatures they are.  I could spend an entire blog post describing the mouthparts alone, but to keep it short I’ll just point out the four palps (the little appendages that look like extra arms) at the bottom of its face that help manipulate the leaves or other food before it gets to the mandibles.  I wonder if I can get something like that for my kids…  Based on the state of our kitchen floor after meals, silverware doesn’t seem to suffice for transporting food cleanly between their plates and their mouths…

Another feature that stands out in this photo is the circular spot in the middle of the grasshopper’s “nose”.  That spot is one of three ocelli, or simple eyes, that complement the two large compound eyes.  (The other two ocelli are right above the base of the antennae.)  Many invertebrates have these ocelli, but there is some apparent disagreement among scientists about what they’re used for.  One possibility is that they simply register light and dark  – perhaps to help see the shadow of a little kid trying to catch the grasshopper and pull its legs off?

What I love most about this photo is the leg joint on the left side of the photo.  It looks just like a hinge I’d expect to see in one of my son’s Lego sets.  Very robotic – who knew?

If you want to read more about grasshoppers – including their complex communication strategies – you might be interested in a short article I wrote for NEBRASKAland magazine.  You can read that here.

I wonder if there are any insects that AREN’T fascinating?  I’ve not met one yet.

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About Chris Helzer

Chris Helzer is an ecologist and Eastern Nebraska Program Director for The Nature Conservancy. He supervises the management and restoration of approximately 4,000 acres of land in central and eastern Nebraska - primarily along the central Platte River. Chris is also the author of "The Ecology and Management of Prairies in the Central United States", published by the University of Iowa Press.
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12 Responses to Photo of the Week – The Prairie Ecologist

  1. Texasrancher says:

    Although they are interesting creatures, and the numbers of species I see amaze me, when you are trying to save your crop (thus your livelihood) from a massive grasshopper plague like we experienced this summer, grasshoppers really are an adversary. This summer was the second time in 10 years we experienced the devastation they can cause; defoliated pastures, shrubs, and trees over thousands of acres. Anything green; even spanish dagger and agave leaves. As you so rightly state, grasshoppers truly are a major ecological force on the prairies.

    • Chris Helzer says:

      Absolutely right. There’s no doubt that very significant damage can be caused by high numbers of grasshoppers. And that damage – especially during drought years – can be a huge hardship on agricultural operations. It’s also true, though, that only a very small percentage of grasshopper species can cause that kind of problems. I don’t have any problem with targeted control programs that go after problem grasshopper species when they’re causing significant damage. I DO have a problem with control programs that spray for grasshoppers annually without first checking to see what populations will be like that year (at least in Nebraska, they have a pretty good strategy – as I understand it – for predicting grasshopper outbreaks and for coming up with appropriate responses in rangeland).

      I and the rest of the country sure hope you get some rain soon.

      Chris

  2. James C. Trager says:

    I have long thought that grasshopper mass migrations (“swarms”) and population fluctuations are important disturbance factors of the prairie, especially in the western part where you are, that need to be mentioned along with climatic vicissitudes, fire and grazing. And yet, there doesn’t seem to be much evidence of this, or much for grazing even, for the eastern tallgrass prairie region where I live. So much we still don’t (and may never) know…
    Anyway, I’ve been getting into grasshopper taxonomy lately, perhaps a good way to give my eyes a relatively restful pursuit, after a lifetime of straining at gnats – er, I mean, ants.

    • Chris Helzer says:

      Did you really just use the word “vicissitudes” on my blog site??

      • James C. Trager says:

        So it seems. I hope that’s okay. Otherwise, you have the power to edit to the term of your choice. ;~}

    • James McGee says:

      James, I have been giving consideration to introducing ant species into local prairie restorations. However, I am having trouble
      identifying ants. Do you have any suggestions of how to get started? I’ve consulted my Audubon insect book and looked at Ant Web. However, I think I need a key or at least a more detailed reference. Do you have any suggestions about introduction methods?

      James
      james_andrew_mcgee@yahoo.com

      • James C. Trager says:

        James — I’d very much like to discuss this with you, but am really tied up for the next few days with a big family event. Write me next week at jamesDOTtragerATmobotDOTorg so this doesn’t fall through the cracks…..

  3. Matt Peters says:

    I was truly impressed by the diversity of grasshoppers I encountered while working in the loess canyons area of Nebraska this summer. Many were remarkably beautiful in addition to the important ecological roles you mention. I’m amused by your comments on the ability of their mouthparts to determine what is good to eat. I found them to have a special taste for field equipment in addition to more natural foods. They scalloped the edges of pin flags and flagging, ate half way thru a standard reel type tape measure, and chewed the rubber gaskets on my GPS unit. Is it possible that they are able to derive nutrition from plastics and rubber (not to mention my datasheets and even clothes!) Given their (I have no idea what species unfortunately) seeming fondness for these materials perhaps biomimicry folks should be researching them for clues to recycling or biodegrading plastic wastes. Or maybe, like a dog, they just enjoy a good chew toy?
    (By the way, Howdy Chris, really enjoying this blog!)

  4. Dan Staehr says:

    Love those grasshoppers photos Chris. When I was a teacher/naturalist at Pioneers Park Nature Center in Lincoln, I used to grab a grasshopper and flip it into the web of one of those huge argiope’s (spelling) to show the kids how spiders will wrap their prey in a ball of silk to eat later. Also, of course when I talk about life cycles and compare butterflies to other insects, grasshoppers are easiest to explain difference between complete and incomplete metamorphosis.

  5. Pingback: Why I Care About Prairies and You Should Too | The Prairie Ecologist

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