Are implants on lionesses best way to protect rhinos?

Tuesday, September 29th, 2020 00:00 |
Are implants on lionesses best way to protect rhinos?

This unorthodox method to avoid predation on the endangered species has elicited mixed reactions, with experts chipping in on how it should work.

It looks, on the face of it, like a most noble initiative: the government, concerned by the rampant predation of one species that could culminate in its extinction by a super predator, has devised a means to save the endangered species. 

Not everyone is happy, though. Predictably, the initiative has attracted both applause and opprobrium, the latter from animal rights activists for whom the end doesn’t justify the means in this case.

In July this year, the Kenya Wildlife Service (KWS) announced plans to implant contraceptives in a number of lionesses, as a way of preventing conception. In the bigger picture, KWS seeks to reduce the predation of endangered species.

 “It is an experiment on a pilot basis at Lewa Conservancy, in Laikipia County”, said Patrick Omondi, of the KWS.

“This is a fenced black rhino sanctuary, and there were cases of lions predating on black rhinos”.

Omondi is the director of biodiversity research and planning at the organisation.

He told People Daily that in addition to preying on rhinos, lions had been targeting livestock in the conservancy’s neighbourhood.

The rapacious adventurism of this big cat is a recipe for conflict with livestock keepers in the region.

 “Occasionally, lions would break out and prey on livestock, bringing predator-human conflict.

To manage that, the board of trustees approved– on a pilot basis - a contraception that would delay birth giving. We did an implant on four lionesses,” he says. 

The contraception is a reversible operation, adds Omondi. Similar to the case in humans, where it can delay conception for a period of, say, three years, this procedure will be reversed.

If successful, KWS will deploy the method in other fenced rhino areas.

But what justifies the use of this procedure?

Acclimatising challenges

“The rhino is critically endangered, internationally. When we have species-species conflict, then we have to take other interventions,” Omondi explains.

The procedure is the best pick on a list of options, among them translocation.

Moving  the lions, however, would disconcert them as they may find it hard to adapt to the new settings.

“Once they learn how to hunt in an area, and you move them, they have a challenge acclimatising and knowing how to hunt.

They, therefore, look for easy prey, thus increasing human-predator conflict. They end up being killed in new areas.

That’s why we are exploring new innovations that have been used in Southern Africa mostly,” he adds. 

Black rhinos once roamed and thrived in Africa’s landscape, largely unhampered by poaching and other threats that have over the years conspired to drive them to near extinction.

The Lewa Conservancy observes that in the 1960s, there were an estimated 20,000 black rhinos in Kenya.

This number would sharply plummet to less than 300 in a span of two decades, thanks largely to poaching.

There are now over 600 black rhinos in Kenya, although the animal remains critically endangered.

Professor Moses Makonjio Okello, while welcoming the initiative, says the concept must be applied with caution and strict adherence to relevant scientific guidelines, seeing as it might have long-lasting consequences on not just lions themselves but the ecosystem.

A similar project, he says, went awry when applied on elephants in Amboseli National Park. 

“We have tried this in elephants before, and we found out that the female remained in season for a long time, and so she was harassed by males, causing stress to itself, to calves and the entire family structure.

If we try that on lions, do we know how it is going to affect other members because, as you know, lionesses live in a networked family?” asks the professor of Wildlife Management and Tourism at Moi University and also School for Field Studies (USA) who has done extensive research in wildlife ecology, wildlife conservation and ecotourism.

Last resort

Contraceptive implants should be a last resort, the professor avers. Perhaps, the question of lions preying on rhinos in a given habitat should trigger questions about why the lion is turning to this particular species and not its preferred sources of food.

The rhino, Professor Makonjio tells us, doesn’t exactly constitute the tastiest meal for the lion’s palate.

“Do we have enough science and understanding to solve the rhino problem by impacting lions as well?

It is important to understand and study why lions are preying on rhinos. Is there a problem with other prey species?

Is that species in the right abundance? Is it in the right mix? There are food preferences: We know that lions prefer zebra and wildebeest.

Are those prey species available in abundance, and can we do something about them that will release pressure from rhinos?”

A lion venturing into human spaces to prey on livestock or humans is symptomatic of this phenomenon. 

“That is just opportunity, just as lions prey on livestock or kill human beings. It is just opportunistic response. It is not a preferred prey,” he explains. 

Population studies, as the professor professes, show that some prey species can easily multiply, including the wildebeest and Zebra, which has a low infant mortality rate.

A good starting point would, therefore, be to check on the status of the lion’s preferred prey, before applying other interventions.

Translocation should be an option, too, seeing as it has been done on problem animals in the past, and options exist for translocating lions from Lewa to the same eco-region within Laikipia county. 

By and large, Professor Makonjio conceded that the contraceptive implants would be justified by the strength of parallel procedures in other regions, provided that it is not the ultimate solution. Even, then, this concession comes with a proviso.

“We can rely on similar studies done elsewhere, provided they are conducted in exactly the same way, with the same hormones, and same monitoring protocols.

It should be done not as a permanent action or solution, but as an expanded study to understand response of different lions in different locations to that approach,” he concludes.

More on Lifestyle