Timelapse Bison Photos

Regular readers of The Prairie Ecologist are familiar with our timelapse photography project at The Nature Conservancy’s Niobrara Valley Preserve.  With the help of Moonshell Media, we set up nine timelapse cameras to capture the recovery of the Preserve from a big wildfire that swept through in 2012.

The cameras are supposed to be taking a photograph every hour during daylight hours to document what happens in front of them.  However, during 2013, we had a few issues with the cameras that led them to take photos much more frequently (and then run out of space on the memory card).  That led to some gaps in our coverage, but the silver lining is that it also gave us some very nice series of photographs over some two to three hour-long periods.

Twice during those frequently-photographed periods, bison were in the frame.  Below are two very short videos made from those photo series.

In the first video, the camera was set to record a blowout area – a site where the sand is destabilized and blown by the wind.  Blowouts are generally disliked by sandhills ranchers because they lack forage and tend to spread unless they are excluded from grazing and allowed to “heal”.  On the other hand, blowouts are ecologically valuable because of the habitat they provide to a wide range of species including plants (including the federally-listed blowout penstemon), tiger beetles, lizards, and many more.   This video shows that blowouts are also attractive to bison.  The video runs from approximately 7:30am to 10am on June 28, 2013.

We put one camera high atop a tall windmill tower to capture a landscape view of burned sandhills prairie.  During this video, the same herd of bison shown above wanders through the frame during a two and a half hour period on the afternoon of October 8, 2013.  As you can see by the color of the vegetation, most plants are in or near dormancy by this time of year, so the bison are picking and choosing what they can find to eat.  The bison at the Preserve get themselves through the winter without supplemental feed from staff, so October food is probably pretty attractive compared to what’s available in February…

These short bursts of timelapse video were not the expected product of this project, but have turned out to be some nice bonus coverage.  Fortunately, the gaps caused by full memory cards are not long enough to seriously disrupt the bigger story of long-term recovery.  I’ll continue to bring you that story as it emerges.

 

The Magic (?) Stick

Ok, this is something I can’t explain – I’m hoping someone else can help.

The slideshow below consists of a series of images taken about an hour apart last June by one of the timelapse cameras at The Nature Conservancy’s Niobrara Valley Preserve.  Hover your mouse over the images and you can click the arrows to move between photos.  Watch the stick in the foreground…

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What in the world?  The stick doesn’t do it most days, but on some days, the timelapse camera captures one end of the stick rising into the air.  Overnight, it returns to its previous position.

Here it is again, a couple weeks later:

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Later in the season, the stick was dislodged so one end was no longer in the ground.  It still moved, but in more of a twisting motion.  I think the stick just to its left is moving slightly as well?

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This is not a living entity.  It’s a stick; dead and disconnected, but still able to move.

My best guess at an explanation is that the stick is moving because of moisture.  Over time, the stick absorbs moisture and then dries out, and the shrinking and swelling of the wood could change its shape.  Because humidity tends to rise overnight and fall during the day, that could explain the pattern.  But, if daily humidity patterns are affecting the stick, why doesn’t it happen more often?  Also, in the October series above, the stick was lifting as it rained, so that seems counter to my hypothesis…?

Anyone else have an explanation?  I love a good mystery…