Meet the People Who Want to Turn Predators Into Herbivores

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CC BY 2.0. What if cats no longer killed? Photo by: Grant Peters/Flickr

A gazelle grazes on the savannah, unaware of the leopard lurking in the grasses, ready to pounce. As the leopard makes its move, the gazelle tries to escape, but it’s too late. The leopard has its teeth sunk into the gazelle’s neck and won’t let go. After some minutes of kicking, the gazelle dies – a feast for the leopard.

It’s hard to not feel sorry for the gazelle, even though predator/prey relations have been part of the natural world for millennia. But what if prey didn’t have to suffer like this?

This is the question posed by philosophers who believe all suffering should be terminated. These philosophers propose that we eradicate predation, so sentient animals never have to feel this pain again.The idea is that to relieve suffering, predators should be genetically altered to no longer be carnivorous.

The Ethics of Human Intervention

“This issue probably hits closest to home, literally, with domestic cats, who are estimated to kill up to 3.7 billion birds and 20.7 billion mammals annually in the United States,” Joel MacClellan, assistant professor of philosophy at Loyola University New Orleans, told TreeHugger. “Be it wild predators or introduced predators such as domesticated cats, the question is whether there is blood on our hands for failing to intervene on prey’s behalf.”

MacClellan's work, and that of other philosophers, has challenged the theories that advocate preventing predation.

In North America and many parts of Europe, the debate on what role humans should play in ending animal suffering has taken shape in protests against slaughter houses, factory farming and animal testing. About 5 percent of Americans consider themselves vegetarian, many motivated by the belief that animals should not be forced to suffer in factory conditions.

Philosophers who believe in predation elimination take that moral stance one step further. They argue that if we don’t want animals to suffer in slaughter houses or tight cages, why wouldn’t we want to end their suffering in the wild too?

“Suffering is bad for anyone, anywhere, anytime,” David Pearce, a British philosopher who published a manifesto on the Hedonistic Imperative, the theory that suffering must be eradicated, told us. “In the post-genomic era, to confine the relief of suffering to a single person, race or species would express an arbitrary and self-serving bias.”

The Consequences

This concept does not always resonate with people. Many argue that we should not interfere with nature, that we should let it run its course.

If predators became herbivorous, they would compete for resources with existing herbivores. This could have negative consequences for plant life and destroy habitats and ecosystems.

Our understanding of the natural world is deeply ingrained in the concept that predators kill prey - think the Lion King and the Circle of Life. We are taught from a young age that natural balance is achieved through this cycle and that we shouldn’t interfere. But predation eliminationists disagree.

“Humans already interfere - massively - with Nature in diverse ways ranging from uncontrolled habitat destruction to "rewilding", big-cat captive breeding programs, the eradication of blindness-causing parasitic worms, and so forth,” added Pearce. “Ethically, what's in question is the principles that should govern our interventions.”

Critics argue that this is based on the assumption that suffering is inherently bad. Should humans be able to decide what’s good and what’s bad?

deer photo

Grand River Conservation/CC BY-NC-ND 3.0

There is also the issue that there is no way of fully grasping the unintended consequences of mass genetic modification on animals and nature. There are concerns that herbivore populations would grow exponentially, though philosophers like Pearce say this could be controlled through fertility regulation. There are also concerns that genetic modification would upset nature’s balance and result in the deaths of many species. Without large-scale tests, the concept of predation elimination remains theoretical.

Plant-Based Predators Could Mean More Disease

However, there are many studies that look at the effects of removing a top predator from an ecosystem. These studies suggest that ecosystems suffer when predators do not help control populations, and the consequences are vast. For example, the loss of wolves and in some cases coyotes and foxes in the North Eastern United States have led to larger populations of mice, carriers of Lyme disease. Many ecologists believe that this has exacerbated Lyme disease prevalence in the region. The same goes for deer populations. Deer provide a breeding ground for ticks, allowing tick populations to grow.

Elimination Versus Reduction

Not all philosophers who have studied the question believe that predation should be completely eliminated, but many do think it should be reduced.

Peter Vallentyne, professor at the University of Missouri, is one of those philosophers. He argues that there are many forms of suffering in the world. To focus all our money and energy on preventing suffering through predation would be to ignore other moral issues like starvation or child abuse.

“I think we have some kind of duty to help other human beings at least when the cost to us is small and the benefit to them is big,” said Vallentyne. “People say those don’t apply to animals and that’s where I don’t understand why not. They are capable of having good lives or bad lives, of suffering or having joy. Why don’t their lives matter just as much as ours do?”

But even the reduction of predation has effects on ecosystems. A study in the 70’s found that the hunting of sea otters caused kelp forests to collapse. Otters had kept sea urchin populations down, but once their population was drastically reduced, urchins feasted on kelp to the point of over-consumption. Kelp has an important ecological function and can support hundreds of thousands of invertebrates. Though otters don’t eat kelp, they played a role in its maintenance.

"The view that we should prevent predation underestimates ecological considerations, as we see from the dire consequences of eliminating keystone predator species, and it is committed to a narrow view of value: only pleasure and pain count," said MacClellan. "If we also value biodiversity or the freedom and independence of wild animals and the rest of nature - or if it is not our place to judge - then we should not prevent predation."

Humanity's Role in Nature

Another big part of the predation elimination plan is the role of humans. Humans are the world's biggest predators--every year we eat 283 million tonnes of meat. The debate about whether to become vegetarian or vegan is already a major discussion in society and a very small percentage of the world's population willingly gives up meat. To spread this globally would be a major challenge.

What do you think?

Should humans phase out predators?

Update: Joel MacClellan is not an advocate of predator elimination - he has studied the ethical debate and challenged it through his work. The original article did not address his stance clearly. His final quote was added later to clarify this. In addition, the headline was changed for further accuracy.