In 1983, 32 Heck cattle were introduced at the Oostvaardersplassen. In 1985, 20 konik horses followed as did 57 red deer over the course of 1992 and 1993. The animals have since been counted once every three years, among other things, using aerial surveys. The herds have developed naturally and the largest number of animals so far was a total of almost 4,000 animals in 2008.

Winter die off

Every winter entails a reduction in the number of animals as food supplies in the area are a determinative factor for the number of animals that can survive the winter. The International Committee on the Management of large herbivores in the Oostvaardersplassen (ICMO) determined that winter die offs of up to 30% should be considered normal. Over the 2009 - 2010 winter approximately 25% of the animals at the Oostvaardersplassen died.

Footage

25% is well within the standard that is scientifically acceptable, but we realise that this still concerns quite a large number of animals. And that is not a pretty sight and definitely not one we are accustomed to in the Netherlands. We understand that this affects people.
In early March 2010, the television programme ‘Eén Vandaag’ showed footage of a dying deer tumbling into water after it had been flushed out of its rest area by a visitor. Staatsbosbeheer is of the opinion that this does not provide a representative image. To start with, the visitor entered an area that had been closed off to visitors for a reason. However, the programme occasioned an emergency debate in parliament on 17 March 2010.

Dynamic equilibrium

In an ideal situation, roughly the same number of animals should die as were born. Since 2008, figures seem to suggest this. Nevertheless, there will never be a constant number of animals over a succession of years as the food supply always fluctuates and animals also die due from other causes.

Figures

Recent figures on the numbers of animals at the Oostvaardersplassen can be found under the heading Facts & Figures.