The Nature Conservancy’s Niobrara Valley Preserve (NVP) on the northern edge of Nebraska’s sandhills is a pretty amazing place.  I had the chance to spend a couple days there last week, something I always enjoy.  While there, I managed to get a few photos of bison from one of the two herds on the property.

Three bison bulls on the edge of burned sandhill prairie - The Nature Conservancy's Niobrara Valley Preserve, Nebraska. These three bulls were feeding in the burned area until I wandered along with my camera. They then kept a safe distance (for both of us) as I hiked past on the trail. Click for a larger view.

In addition to being an important site ecologically – and a beautiful place to visit – the NVP was also a key site in the development of the fire/bison grazing model that eventually developed into today’s patch-burn grazing.  Al Steuter and others used the Preserve as an incubator for the initial idea of moving bison grazing intensity around large prairies by shifting the location and season of fires.

I’m often asked about the differences between the way bison and cattle impact prairies.  As we continue to experiment with patch-burn grazing, we’re finding that the forage selection differences (they way they choose which plants to eat) between the two animals are pretty slight when they’re managed with patch-burn grazing or similar systems.  Under light stocking rates, both bison and cattle prefer to graze in recently burned patches, and both prefer grass over wildflowers and other plants.

The major differences between bison and cattle appear to be mostly behavioral.  Cattle like to walk in single file, forming trails, while bison tend to move in loose groups.  Cattle tend to sit/stand/poop in water on hot days, while bison don’t hang around water or shade for long periods.  While these can be important differences, there are ways to mitigate the more negative impacts of cattle – e.g.  fencing out sensitive areas and/or keeping stocking rates low.   

On the other hand, there are some disadvantages to using bison to manage prairies instead of cattle.  These are mostly logistical.  With rare exceptions, it’s not possible to lease herds of bison, so if you run bison, you have to own them.  Among other issues, that usually means an annual roundup for innoculations and sorting of animals to thin from the herd (assuming you don’t have unlimited land).  It also means big strong fences and corral systems.  In short, bison can be expensive and time-consuming.  Also, they work best in prairies of several thousand acres or more.  On those large prairies, they can be an important part of good prairie management.  On smaller prairies, cattle can be a very good substitute, if managed carefully.