Calving & Adapting To Us
Things tend to happen all at once this time of year, or so it seems in the southern plains, leaving us charged with thinking ahead and managing for stepping aside and letting nature take its course. Calving problems can happen with bison. Heifers do heifer things like spook at the new shadow, cows can choose ‘the herd’ over a slow-starter, and young bulls can be a problem if they confuse the scent of calving with estrus. It is also true that 90% of the fetal development occurs in the last trimester of pregnancy. This is not specific to bison and we just need to be careful with over feeding during that period to prevent [causing] calves too big at birth. The catch is; adequate nutrition is required for healthy reproductive function. Personally I like to save my supplemental feed budget for the breeding season and keep the rest of the year limited to mineral, forage and worming. If your management has resulted in thin cows during the last trimester and calving, it’s best to wait till breeding season to feed them out of trouble. Make no mistake – thin cows can be in trouble! Some of the boxes to check going into calving might include:[ 1]an orphan kit / just in case  no feeding if forage is adequate  letting them calve in zones with mostly open grassland to mitigate predation and maternal disconnect  making sure you have mineral out  relationship with a veterinarian familiar to the herd &  as much of your absence as you can supply them. Calving season should be the lowest labor cycle in your program for many reasons. Personally, I think the best reason is that we want the species to remain independent of people as much as possible. As managers, we strive for better and stronger bison every year. Better bison, like better anything, involves genetics, but has even more to do with nutrition.
Bison may be re-adapting to plenty of good nutrition and achieving their former physical glory and wild state of big – because they are captive! Pre-Columbian bison would have moved from feed to feed, leaving behind perfectly tillered and conditioned soil for re-growth and the return of grazers. I can defend this thesis because I have a time machine. That’s right, I have a time machine and it’s called a bison herd… I know how far they can walk in a day’s work, why they move and how predictable their nature tends to be. They are the perfect intensive-rotational-mob-grazer that forward thinking ecologists and land stewards strive to emulate with domestic animals. So; prehistoric bison would have managed their own nutrition toward optimum and ‘fed’ their genetic makeup to unmitigated fruition. Today, more and more folks are learning about managing habitats for healthy bison, and the economics warrant the investment in the land – and the herd. Fences that once denied nutrition literally, now disappear metaphorically because they grant it. Here’s the catch; because all bison are captive, and all bison are managed somehow either by way of denial or grant, there’s a place for philosophy. Personally, I choose the philosophy of keeping it simple and not causing reproductive dependence on people. That sounds noble and conscientious, but it gets tuff when doing the right thing for the species costs money. This is what sets the bison rancher apart from the crowd, and why bison ranching is not for everyone. Bison are nature’s great adapters, which by evidence over the last 100+ years, – are (!) adapting to us.
For more about orphans – go to the archives and read: Southern Plains Pointers, April 2014