Tag Archives: insect

Coneflower Surprise

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Last Friday, I was at my in-laws’ farm in eastern Nebraska (Sarpy County).  Toward evening, the hot, sunny, windy day transformed into a cloudy evening with light winds.  I stepped outside to look over the little patch of restored (reconstructed) prairie in their front yard.  The sun was going down behind the clouds, but there was a small gap of clear sky between the clouds and the horizon.  Foreseeing a small window of time with some good photography light, I went back to the house and grabbed my camera and tripod.

As I came back out of the house, the sun was just coming out from beneath the cloud bank.  There were only a few places in the little prairie that were being hit by the low-angled light, and the best color in the prairie seemed to be the gray-headed coneflowers that were just starting to bloom.

Gray-headed coneflower (Ratibida pinnata). Reconstructed prairie in Sarpy County, Nebraska.

I chose a flower and set up the tripod to photograph it.  After only a couple of shots, a stink bug flew in and landed on the flower.  Just as I began focusing on the stink bug to see if he’d pose for me, a crab spider suddenly squirted out from inside the canopy of coneflower petals and grabbed the startled stinkbug.

A fuzzy first attempt to photograph the stink bug immediately after it landed.

Initially, it looked like the spider was having a hard time finding a place to bite the stink bug through its tough carapace, and for a minute or so, the bug was pulling the spider around the flower and it looked like an even chance that it would escape.  However, the spider eventually latched onto the bug near its rear end and hung on tight.  The stink bug continued to crawl around the flower, hauling its spider cargo with it, but over the next few minutes, the pauses between movements became longer and longer.

The stink bug pulled the tenacious spider around the flower, but the spider hung on tight.

In this photos, you can better see where the spider sunk its fangs into the bug (soft underbelly?) Eventually, the stink bug stopped moving altogether, and it was game over.

As the sun went completely below the horizon, the stink bug finally stopped moving altogether.  After a few more minutes, the crab spider let go and rotated the bug into a new position within its grasp – apparently to feed?  I’ve watched crab spiders attack and feed quite a few times before, but don’t remember seeing one changes positions to feed – they usually seem to just feed through the same initial fang holes they make to kill their prey.

A few minutes after the stink bug gave up the ghost, the spider flipped it around in its grasp. This photo was taken several minutes after the sun had gone down.

Right after the above photo was taken, the wind kicked up, and it felt like a storm was coming, so I left the spider to its meal and went inside – feeling grateful for the opportunity I’d just been given.  Who needs TV??

Photography Notes

For those of you who are photographers, you might be interested in a couple things about this photo series.  As I said earlier, the sun was low in the sky.  It was a nice red color, providing great warm light on the flowers and bugs.  However, the light intensity was low, and there was a slight breeze that was moving all the plants back and forth a little.  I set my camera’s ISO on 500 to allow me to take the photos at between 1/25 and 1/50 of a second, which was sufficient to stop the motion.  The trickiest part was timing the shot between wind gusts so that the eyes of the stink bug were in focus (or, a few times, the eyes of the spider).  I shot about 50 photos over 10 minutes or so, and about 15 turned out sharp.

The last photo above was the trickiest because the sun had been down for a few minutes, and there was no direct light at all.  It was too dark to stop the wind-driven motion of the flower, so my only chance at getting the last shot – which was too good to miss – was to use flash.  Unfortunately, I don’t own a flash other than the pop-up flash on my Nikon 300s camera.  So, I popped up the flash and set the camera on Program.  Having tried to use the flash for macrophotography before, I knew that the flash alone was too bright for close-up shots, so I improvised.  I pulled my arm out of one sleeve of my t-shirt and wrapped the shirt sleeve over the flash and then took the shot.  The shirt acted to diffuse the flash’s light but still allowed enough light for the photo to work.  It took a couple tries to get the focus right (the stupid flower kept moving!) but it eventually worked.  I’d never tried this little trick before, but now I might have to throw an old t-shirt into my camera bag for similar future emergencies!  (or maybe just the sleeve…)

Butterfly Aggression

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We started seeing our first regal fritillary butterflies of the season last week, and began our second year of data collection on their habitat use in the Platte River Prairies.  As always, male fritillaries have emerged first and now have to wait a couple more weeks before females arrive on the scene.  In the meantime, they do some nectaring, but mostly seem to just fly around.  They look like a bunch of teenage boys who arrived at the school dance before the girls…

A regal fritillary butterfly seen last week in the Platte River Prairies, Nebraska.

The above regal fritillary was nectaring on a plant that will remain a mystery until my next post (sorry).  I was expecting to see them nectaring on common and showy milkweeds (Asclepias syriaca and A. speciosa) because those plants were just starting to bloom.  In some studies of regal fritillaries, milkweeds are major nectar plants.  Last year we saw regal fritillaries using hoary vervain (Verbena stricta) more than anything else, but I didn’t see a lot of milkweed blooming last year – for some reason.  This year, I figured maybe we’d see something different since milkweeds seem to be having a good year.

As I walked around checking milkweed flowers for butterflies, I saw a number of insect species using them, but none more abundant than the gray copper butterfly.  In fact, I saw one flower that had six coppers on it at the same time.

A gray copper butterfly on showy milkweed. The Nature Conservancy's Platte River Prairies, Nebraska.

I did see a few regal fritillaries nectaring on milkweeds, but surprisingly few, given the high numbers of both fritillaries and milkweeds I was seeing.  Eventually, I decided to just sit for a few minutes in front of one milkweed plant to watch the gray copper butterfly that was nectaring on it.  I figured I’d get to see a parade of other insects come by and nectar there as well.

I saw a fritillary making its way toward the flower and got my camera ready so that I could capture both the fritillary and the copper on the same flower.  However, when the fritillary got within a few feet of the flower, the copper suddenly erupted off the flower and flew straight at the fritillary, chasing it like a small bird chases a hawk.  The fritillary swerved off and sped away.  I saw the same thing happen twice more within the next several minutes.

What looks like a peaceful scene with a pretty butterfly nectaring on a flower belies the bottled up aggression waiting to boil over when another butterfly strays too close...

Throughout the day, I saw the same aggressive behavior by coppers on other milkweeds as well.  It’s hard to say, of course, whether the coppers were really protecting their nectar source, but that’s what it looked like to me.  There has been considerable discussion in the scientific literature about whether or not male butterflies (of some species) defend territories like birds do – keeping other males away.  There seems to be consensus that at least a few species do.

What I was seeing, though, was not mating territory defense.  Assuming that coppers can recognize the difference between their own and other butterfly species, they didn’t appear to be chasing away potential competitors for mates.  Instead, they appeared to be monopolizing a valuable food source.  Even when there were multiple milkweed flowers on a plant, or several plants in a clump, coppers successfully chased fritillaries away as they approached.  Interestingly, while coppers wouldn’t tolerate fritillaries, they didnm’t seem to mind sharing flowers with other coppers…  There weren’t many individuals of other butterfly species around, so I didn’t get a good feel for whether coppers chased away all other butterflies or just fritillaries.

I’ve not seen or heard of this kind of behavior before, but I’m sure other people have.  I’d sure appreciate hearing from you if you know anything about it.

Aggressive butterflies… who’d have thought?