Bears as Predators ~

[CrysOmega]

The Bears are Awake!

On February 28, Megan and I were hiking on wolf tracks in separate areas, and nearly simultaneously came across grizzly bear tracks.  This is quite early, since the bears usually come out mid- to late-March.  The second I came across the fresh grizz tracks, all of my senses came alive.  And just moments before, I had blundered through an old bison carcass.  Yellowstone, in an instant, has changed.  For us, we can no longer saunter along with our heads down, following wolf tracks, getting lost in our thoughts.  To do so could be fatal.  The bears are very hungry and also very protective of any food they find.  During normal winters, there is plenty of winter-killed elk and bison for the bears to scavenge on, but this winter has been far from normal.  All of our necropsied kills have plenty of marrow fat remaining and we have found no animals that appeared to die due to the winter, so the bears will probably have to do some hunting for themselves or steal kills from the wolves.

Later in the week, we were alerted to a bison carcass by Caroline, an interpretive ranger.  With much yelling and eyeing of the forest edges, we flushed the 30+ ravens off the carcass as we approached.  The necropsy found significant subcutaneous hemorrhaging on the hump of the very healthy (lots of fat in the hump and marrow) cow bison, indicating that she was killed by a bear.  Grizzly bears often attack from the front, as opposed to wolves, which typically attack from the rear.  The bears basically give their prey a good swat in the face or jump them from the side and latch onto their back.

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