Hunt a rhino, save an ecosystem?

Once on the verge of extinction, black rhinos in South Africa's national parks have made a spectacular comeback. Under the country's aggressive conservation programs, the mammal's population has grown by more than 50 percent in the past decade. But that success has brought a new challenge: how to control a population in limited conservation space.

Now South Africa is weighing a controversial measure that would allow hunters to kill five old male black rhinos a year, which could raise $200,000 per kill. Allowing hunting, some experts say, has helped resurrect the white rhino population, which now stands at 11,000 worldwide, from a low of 200 at the turn of the 20th century.

Supporters say it can also raise much-needed conservation cash. But critics say rhinos and other animals in abundance here are still endangered elsewhere in Africa.

"The general feeling is that we have a problem and that problem isn't going to go away," says Kevin Rodgers, a professor of ecology at the University of the Witwatersrand here. Mr. Rodgers is heading a scientific review of the impact of elephants - whose population has ballooned to 12,000 from 8,000 in 1994, when culling was stopped - on behalf of the South African parks. "Eventually, we're going to have to make hard decisions," he says. He will submit his findings to park management Monday.

Most conservationists, Rodgers says, agree that some of South Africa's parks are fast reaching carrying capacity for certain animals. Too many elephants in Kruger National Park, the gem of the country's park system, threatens other species, like eagles, since feeding elephants often knock down the large trees in which they nest. An overabundance of large male rhinos leads to often fatal fights between males and can hinder population growth by distorting the balance between males and females.

But exactly how many elephants or male rhinos are too many and what to do about the problem remains controversial. Some animal-rights organizations say that killing should be a last resort.

Considering that animals like black rhino and elephant remain endangered across the continent as a whole, they argue, excess animals should be moved to other parks with small populations, like reserves in Mozambique and Angola where large game was virtually poached out during long civil wars. Others advocate the use of contraceptives to control the elephant populations, although many scientists question the cost of such a program and whether it would be effective.

But others argue that in certain cases, the killing of animals can actually benefit conservation and species preservation. They say that money from the sale of culled ivory can help fund national parks, while limited hunting in private reserves can actually increase the value of species and create incentives for their protection.

Martin Brooks, chairman of the World Conservation Union's African Rhino Specialists Group, says controlled hunting of Southern African white rhino encouraged private land owners to stock their land with the large grazer, helping to pull the species from near extinction. Today there are more than 11,000 of the animals in the world, more than 10,000 of which are in South Africa. About 20 percent of South Africa's white rhinos live on private land, where strictly controlled hunting is allowed on a permit basis.

In contrast, black rhinos, which eat trees rather than grass, have made a slower recovery and there are only an estimated 3,610 in the world. According to the International Rhino Foundation, black rhino populations declined 92 percent between 1970 and 1992, hitting a low of 2,300 in 1992. South Africa wants to allow five to be hunted each year.

White rhinos can bring $30,000 in trophy rights, plus the cost of the safari and daily hunting fees. Black rhinos could bring an estimated $200,000 each, say hunting organizations.

Mr. Brooks, who used to work for the park system in one of South Africa's provinces, says allowing excess male black rhinos to be hunted each year could encourage private land owners to stock the animals. He says that parks like Hluhluwe-Imfolozi, South Africa's oldest, have long struggled with what to do when they had too many male black rhinos.

"If you're going to kill an animal, it makes sense that it should have some conservation benefit," he says. "If it's the private sector that does that ... then that's an incentive for them to invest in black rhino populations for breeding, which is good. If the formal conservation agency allows hunting, or sells the surplus animals to private owners, that money goes back into the parks system."

But Jason Bell of the International Fund for Animal Welfare (IFAW) says the idea that nature conservation should be economically viable is dangerous one. "I think there's a very strong movement worldwide which is trying to promote the use of wildlife and natural resources, sometimes to the detriment of species," he says. "What we're seeing in Southern Africa is the view that natural resources need to have an economic value to have a place in our world."

The fundamental problem, says Rudi van Aarde, director of the Conservation Ecology Research Unit at the University of Pretoria, is that South Africa's parks are artificial spaces, essentially large zoos where natural processes no longer work to keep animal populations in check.

Unlike in East Africa, where animals are allowed to roam freely in and out of official parks, most of South Africa's parks are fenced and many have man-made water holes. This stops normal migration patterns. Van Aarde and supporters, including groups like IFAW, have a grand vision of interconnected, unfenced conservation areas. In these more-natural ecosystems, elephants would die naturally during normal drought cycles, and their impact in any specific area would be limited through natural movement.

"What's the benefit of this? We'll have large conservation areas instead of small conservation areas. We'll have natural limitation of numbers rather than unnatural limitation. We'll have cost-effective conservation instead of costly conservation," van Aarde says.