Sunday, January 23, 2011
Pronghorn and Fences
Pronghorn have problems crossing fences. Unlike Mule Deer or Whitetail Deer, which have no problem jumping fences, Pronghorn do not like crossing them at all. Not all fences are equal though and although some are nearly impenetrable, others can be designed to facilitate Pronghorn movement. Most often Pronghorn go under fences and fences can be constructed so that the bottom wire is not barbed and sits a bit higher from the ground to allow easier passage underneath the fence. However, when the snow becomes too deep, even well designed fences can be barriers to movement.
This fence does not have a smooth bottom wire and with the depth of the snow decreasing the amount of free space, the barbs are pulling lots of hair from the Pronghorn as they pass underneath.
Last week I watched a number of Pronghorn trying to move back and forth across an old roadway that has a barbed wire fence on either side.
Many of the animals would not cross the fence. Others made up their minds and jumped the fence. There was no option to go under with the amount of snow leaving only the top two wires exposed. All the animals that jumped the fence were moving downhill, following a path through the deep snow that others had made earlier.
Other groups tried to follow the same path uphill. None of them made the leap going that direction.
I watched a number of individuals get this far, ponder the leap, then turn around and head back downhill. The fence apparently was too much to get over heading uphill.