Leopard conservation in a spot of bother

A study by Dr Lourens Swanepoel, a post-doctoral fellow at the University of Venda, focuses on carnivore conservation and management. Its author spoke to Gerhard Uys about his extensive research on leopards.

Leopard conservation in a spot of bother
Research by Dr Lourens Swanepoel shows that says that there is no easy way to determine leopard populations, and this complicates conservation efforts.
Photo: Nan Smith

What was the focus of your research on leopards?
We wanted to evaluate the viability of the South African leopard population under realistic scenarios of natural and anthropogenic (human- induced) mortality. Current leopard conservation plans (up to 2010, at least) did not take into account all mortality sources in the setting of harvest quotas, which could impact negatively on long-term population viability.

In the course of your research, you developed a model to determine a likely population for leopards in South Africa. How does it work?
We first created a habitat suitability model for leopards across South Africa. We then collated all leopard density data from credible studies in South Africa and related suitable habitat to leopard density estimates for that specific habitat. From this, we extrapolated, or rather predicted, leopard abundance to suitable habitat where we didn’t have density estimates.

You refer to the effects that the killing of male leopards as opposed to females can have on the population. Please elaborate on this.
Females produce the offspring, so it stands to reason that removing them has an impact on the numbers of the next generation. Each male leopard overlaps several females, so removing a male will have less impact, as another male can inseminate the females.

However, excessive removal of males will increase the infanticide rate – killing of conspecific young largely due to sexual selection – which would also affect the population negatively.

At a recent public address, you said that in Limpopo, where game farms abound, your research found that leopards had a lower survival rate. Please explain.
Our research on the population structure of leopards focuses on the entire South African population. In Limpopo, however, we’ve generally seen an increase in the number of damage-causing animal permits issued to landowners, allowing them to destroy leopards. We’ve also seen an increase in trophy hunts.

This seems to have resulted in the lower survival rate of leopards on non-protected land such as game farms. While lower survival rates are expected on harvested populations, we found that female leopards had particularly low survival rates, which is a cause for concern.

What are the difficulties with determining sustainable hunting quotas for leopards?
It is often thought that to determine a sustainable quota, we need accurate population estimates. However, with a carnivore as elusive and difficult to monitor as a leopard, we simply cannot accurately determine population sizes at the scale necessary (province-wide) to advise management. This is the biggest problem with quotas.

However, there are a few novel statistical techniques being developed for cougars in America, bears in Europe and lions and leopards in Africa, that will allow us to accurately quantify sustainable quotas. This is being done in Limpopo, through Dr Guy Balme and Ross Pitman from PANTHERA, and will eventually apply to the rest of the country.

Apart from accurately determining the population size, which other factors should be kept in mind when determining a sustainable quota?
From previous population models, there is evidence that the removal of old, post-reproductive males (above seven years) will have a negligible effect on population persistence and viability. Combining with the large effect that females play in population persistence, harvesting of leopards should ideally be limited to old males.

What data is still lacking from your research?

We have little knowledge regarding infanticide rates of leopards on non-protected (that is, privately-owned) land and density estimates of leopards are also biased towards protected areas. We also have little information on the number of leopards removed legally and illegally from various land uses, on the movement of leopards between populations and provinces, and on trade in leopards for traditional medicine or clothing. Lack of this data places limits on the conclusions we can draw from population models.

Has the growth in the number of high-value game, such as sable antelope, kept on game farms had any impact on leopard conservation efforts?
High-value game and livestock place several challenges on leopard (and other carnivore) conservation. High-value animals can be protected in two ways – by physically fencing predators out (predator-proof fencing) or by the active removal of predators (damage- causing animals).

The removal of a predator will only create a vacuum, drawing a new predator into the vacant land. Predators thus have to be removed continually until most of them are removed – local extinction in some cases.

There are three main challenges to the conservation of leopards on game farms:

  • Leopards feed on their natural prey, which makes it almost impossible to limit the predation, by using guard dogs, for example;
  • High-value game means that the conservation benefit of hunting a leopard is rarely enough to offset the cost of predation. Trophy fees are distributed to professional hunters and one landowner, while leopards range over several properties);
  • More and more game animals are becoming financially important for game farmers. This means that a leopard’s financial impact increases due to changes in game prices.

For example, in the past, there would have been little concern about a leopard feeding on a steenbok, but with even steenbok prices increasing, such predation will not be tolerated.

The focus of conservation is often in conservation areas. Is this where leopard conservation is most needed?
The majority of suitable leopard habitat is on private land (non-protected and non-governmental lands). Because of this, conservation effort should be particularly directed towards these areas. Also, because leopards often move between protected and non-protected areas, conserving them on the latter will benefit the leopard population in general.

What is the next step in your research?
We are now focusing on spatially quantifying leopard mortality, getting more information on their removal rates and movement. This will help to create risk habitat models that will allow us to predict areas of potential high conflict between leopards and landowners.

What can government do to contribute to leopard conservation?
Government must assist in establishing a national framework to allow for continuous leopard population monitoring such as permit applications, allocation and key population. It should also establish and manage databases on leopard mortality such as damage-causing animals killed and trophy- hunted leopards, and implement, regulate and enforce hunting regulations such as age- or sex-based harvesting.

But the greatest contribution that government can make is to establish a dialogue with stakeholders affected by predators (not just leopards) and set up a programme to facilitate financial incentives for people whose living is affected by predation. This will take a considerable mindshift, but we have to realise that trophy hunting alone will not foster enough conservation tolerance to facilitate the long-term conservation of leopards and other carnivores.

Predation impact affects a large number of farmers. These costs have to be offset via innovative programmes and ideas. Government should take the lead in establishing such a process.

For more information, email Dr Lourens Swanepoel at [email protected].