Successful Boar Population Control No Longer A Secret

The previous article in our series On controlling Wild Pig Populations has shown that the survival rate of young boar, particularly survival rates of female piglets, shoats and yearlings, drives the growth of boar and wild pig populations. Let's sum up the findings of the Austrian researchers.

Let us assume a 20 percent survival rate for piglets and shoats (i.e. 80 percent loss of young boar) in a year of average food resources. The survival rate of mature sows is 70 percent. The blue line in the diagram represents a survival rate of young female sows of just under 50 percent, which must be maintained to keep the population from growing. If it is not, this boar population will continue to grow. The following diagrams show the situation at survival rates of 10, 20 and 30 percent of piglets in times of average availability of food.

Legend:

Vertical axis(x coordinate) - % of surviving female yearlings (gilts) in percent

Horizontal (y coordinate) - surviving mature sows in percent

Green line – percentage of surviving young boar

blue line - total boar population

Small arrows on lines signify increase or decrease of population.

The Austrian researchers also prepared a diagram that reflects the situation when food is abundant. Nowadays, this is almost the norm and nowadays hardly ever the exception because agricultural production and other human activities offer an abundance of non-traditional food sources available boar can use almost at will.

In years when the availability of food is above average a given boar population will continue to grow unless far less than 40 percent of all young female boar survive. In order to keep the boar population at its original level, no more than 20 percent of young sows should survive. All other survival or mortality rates remain the same as in the previous graphic. The graphic below shows how survival rates of young female boar affect population numbers. It is assumed that the survival rate of mature reproducing sows does not change (i.e. stays at 70 Percent).

(Beech nut data courtesy of Dipl.Ing. Rudolf Litschauer and Dr. Siegfried Jaeger.)

Y axis - surviving female yearlings (gilts) in percent

X axis - surviving mature sows in percent

I know. The diagrams look a little confusing. But it all comes down to this:

Put bluntly, about 80 percent of all young female boar and wild pigs must be shot regularly to prevent the growth of any given boar or wild pig population.

For the benefit of our our sensitive animal friends and PETA members we could also say:

Eighty percent of all young boar and wild pigs must be humanly prevented from joining the reproduction cycle in order to keep a boar population stable at their original numbers.

In other words, if more than 20 percent of young boar or wild pigs escape the murdering butchers in their camouflage outfits and 4x4 trucks, a boar population will inevitably increase its numbers.

The more young boar survive, the faster the boar population will expand.

It is a fact of life for wild boar and wild pigs.

And a lesson for animal lovers who are upset because some dastardly wild pig got into their flower garden and rearranged the flower beds to its liking. It also should teach farmers, ranchers and landowners to take action early and decisively instead of banking on additional income from a profit maximized hunting program. The same applies to hunting guides and outfitters.

The best and most successful boar population control is to start countermeasures early and to remove consistently at least 75 to 80 percent of all young boar. Year after year after year; and season after season.

In light of this knowledge we have to ask:

Why do boar and wild pigs overrun many European countries and numerous states of the United States? Why is Texas not able to get rid of several millions of their wild pigs?

Read why in the last article of this series.

PJJ