Monday, September 12, 2011

It's a bug-eat-bug world out there

Shortly after returning from a recent expedition to seek out the fantastic Amorpha Borer Beetle in Scioto County (click the LINK if you missed my report of the successful mission), I was talking to my mom, who asked, "So, when did you get so into bugs? I thought you were into birds. What happened to the birds?" A perfectly legitimate line of questioning for a girl who started out interested in "just birds and flowers, thank you very much." In answer to my mom, and to the rest of you, if you care to know: a number of things have contributed to my burgeoning interest in insects. Having macro capabilities on my camera has probably been the most direct influence. My macro methods are a bit crude, but they do the job for me. Once you start photographing flowers at a macro level, you see things you've never noticed before, and it's only a matter of time before you start appreciating insects from a whole new perspective. Having friends who are into insects helps, too.

I should also mention that studying birds and botany has been a gateway to so many other aspects of the natural world for me. At the upcoming Midwest Birding Symposium, I look forward to hearing my friend Jim McCormac's presentation, "Birders Going Beyond Birds," which will address this very topic!

So, let's take a look at how I view insects as a birder. From a birding perspective, I think about insects as being food for birds: worms for robins, caterpillars for cuckoos, vireos, and warblers, cicadas for Mississippi kites, and those are just a few of many examples I could give. Part of the reason so many birds migrate is because once bugs die off for the year in the northern climes, their food source has dried up, so they better go somewhere else where the eatin's good if they want to survive.

Up until recently, I haven't really thought about bugs from a much broader perspective. So it has been a slow realization to me over the last 6 months or so that, while birds are serious insect predators, perhaps the bigger threat to insects are... other insects. Whether it's falling into the waiting jaws of a praying mantis, getting caught in a spider web, or perhaps the more gruesome fate of having some other insect larva eat you from the inside out (that's what parasitism is all about folks), it's tough to make it as an insect! The following snap-shots were taken during the beetle expedition in Scioto and Adams Counties. Obviously, we saw lots more than just the Amorpha Borer Beetle.

This is a very tiny (think size of a fingernail tiny) robber fly, commonly known as a gnat-ogre. They stalk their prey by hanging out on the tip of a blade of grass or the very edge of a leaf. This gnat-ogre looks to have just gotten started on a meal, and didn't seem to mind having some cameras shoved in its face.

Next up we have a grasshopper-hunting wasp, which is to say a species of wasp that specializes in hunting grasshoppers. The grasshopper blends in pretty well with its surroundings, but the camouflage apparently was no match for the keen eye of the wasp.

Since the grasshopper blends in so well, I thought it might be helpful to isolate the two actors in this scene: wasp is circled in pink/purple, grasshopper is circled in green.

Here you can see that the grasshopper is almost twice as large as the wasp, but she carried it with relative ease, at least to our eyes. We watched her haul this grasshopper several yards toward her burrow in the dirt.

She repeatedly stopped on top of the grass in an effort to locate her burrow, which she eventually found. We watched her excavate the burrow in preparation for the grasshopper (which she presumably would bury inside, where her young would eventually hatch and have a feast waiting for them). After observing that she had trouble finding her burrow, we also noticed she had difficulty relocating her prey after she had excavated the burrow. We finally surmised that our presence may have been the thing that was throwing her tracking off. We had originally hypothesized that she was using some kind of scent queues to help her find burrow and prey, but perhaps she was using visual cues instead, and our movements kept throwing off her bearings (i.e. her landmarks kept changing). At this point we backed off and left her to her job in peace. (Our apologies to you, Mrs. Wasp.)

Here, a praying mantis looks on innocently after it has just caught some species of ambush bug. We watched the ambush bug walk right into the mantis's well-camouflaged trap.

A face that only a mother could love. I've never seen mantis mandibles up close until now.

Chomp! Once again, a very cooperative subject, busy with its meal and obviously not feeling threatened by all the big creatures looming toward it with cameras.

I have some other buggy stuff to share, but we'll take a break and deal with birds for the foreseeable future. Stay tuned for reports from the Midwest Birding Symposium!


Red said...

I applaud you for getting to the nitty gritty and telling about insects. Insects are just one part of the eco system which makes everything work.

Gabrielle said...

Insects ARE cool. I'm just kind of glad I'm not one.

Have an awesome time at the Midwest Birding Symposium!

dAwN said...

Oh yeah~Love me some bugs! Great shots Heather. Have a wonderful time at the MBS!

Trish Callis said...

Neat stuff, Heather!