A plan to let nature take its course

ecology

A stretch of 15,000 acres of swamp and grassland in the Netherlands is the site of a remarkable and controversial experiment that has grabbed the attention of international animal and wildlife experts, says Stanley Reed

On an open plain in Lelystad, Netherlands, in front of us are hundreds of horses. Most of them are gray with black manes and tails. Their heads look more like those of their wild cousins, zebras, than those of riding horses. Some even show what may be a vestigial stripe on their flanks. “We could be in the Serengeti,” says Hans Breeveld, my guide, referring to the plain in Tanzania. Well, we almost could. To the north, we encounter another big group of large animals, this time red deer does with their young. They gaze at us and bleat like sheep. Off in the distance are massive cattle with imposing horizontal horns that look like they might have walked out of a cave painting. Every now and then, a brown harrier, a large and rare raptor, floats by, and we glimpse a white-tailed eagle, another species unusual in most of Europe, perched on a dead tree. Rather than Africa, we are in the Netherlands, one of the most densely populated countries in Europe, at a place called the Oostvardersplaasen.

This stretch of swamp and grassland of more than 6,000 hectares, or about 15,000 acres, is just a 45-minute train ride from Amsterdam. And it is the site of a remarkable and controversial experiment that has been the subject of intense national debate and has grabbed the attention of experts in international wildlife management and animal welfare.
This wild area started as low-lying polder, land that was reclaimed from the sea in the late 1960s. Breeveld, who has worked as a ranger in the Oostvardersplaasen for about 30 years, explained that the idea was to put light industry here, but the recession hit and investors did not come.

In the meantime, a small group of scientists and bird watchers noticed that the marshy area was attracting species like egrets that had become rare or had vanished from the Netherlands. Something special was transpiring.

“This gave a window into what large parts of the Netherlands looked like in the past,” said Frans Vera, an ecologist who has been an advocate for the reserve. Vera and his allies pushed for an unusual form of management, which, as much as possible, allows nature to take its course.

A bold and persuasive thinker, Vera argued that the grassy areas should be cropped not by domestic sheep and cattle but by beasts resembling their wild ancestors. As these species were extinct, he settled on konik horses, Polish descendants of the tarpan, and Heck cattle, which had been bred in Germany in an attempt to recreate the aurochs.
Small groups of these animals, as well as red deer, were introduced in the 1980s and 1990s. By 2010, their numbers had soared to a total of about 4,000, with deer by far the most numerous. In the last couple of years, there has been a decline, with about 2,700 animals counted in April before the breeding season.

As in the Serengeti or any other natural ecosystem, a large proportion of the animals die each year. While access to the Oostvardersplaasen is restricted, trains run frequently along the perimeter of the area, giving passengers a view of dead animals or whatever else is transpiring. “A lot of people were visually confronted with dying animals in the winter,” said Frauke Ohl, a professor of animal welfare at Utrecht University. Critics, including animal welfare advocates and hunting groups, argue that to allow animals that are fenced in — albeit in a large enclosure — to starve is cruel and immoral and that the numbers need to be proactively reduced.

Responding to public pressure, the government convened an international panel of experts, including Ohl, which recommended in 2010 that animals should not be put through the suffering of dying by starvation but should be shot if they look as if they will not make it through the winter. Now, as the grass stops growing and food becomes scarce, the rangers monitor the animals closely and shoot those that look like they are not going to survive.

Critics say the animals are still far too numerous for a place the size of the Oostvardersplaasen. Jozef Linthorst, the chairman of the Red Deer Association in the Netherlands, which looks out for the welfare of the animals but supports hunting, says that when he has visited the Oostvardersplaasen, he has seen hundreds of dead animals on the ground while the living ones are “what we call skin over bones.” Vera and others say the critics are judging the welfare of wild animals according to standards developed for farm animals and pets.

Experts say that the Oostvardersplaasen has been a useful laboratory for seeing what does happen when large animals are reintroduced to a European landscape.

On the summer day I visited the Oostvardersplaasen, the debate, which may be rekindled by a film about the reserve called “The New Wilderness,” to be released this month, seemed to miss the beauty of the ecosystem that had grown up there. A stallion pinned back his ears and growled when he thought we were coming too close to his group of mares and foals. He relaxed as soon as we started to move off. “Which one would you have me shoot? ” Breeveld asked.