Predator Control on Sheep

 Introduction

“Little Bo Peep has lost her sheep,

And doesn’t know where to find them.

Leave them alone, and they’ll come home

And bring their tails behind them.”

We have all heard this little nursery rhyme growing up. It always seemed cute and innocent in the cartoons and books we heard it from.  But as we grow up, we tend to make fun of our childhood memories, sometimes humorously or deviously.  For this nursery rhyme, I had an image in my head of a wolf that said, “Where are Little Bo Peep’s sheep?  THEY’RE IN MY BELLY!”  A pretty funny thought, eh?  Well, it is funny to think about.  But in the real world, the idea of a wolf or any form of predatory animal eating a shepherd’s sheep (whether the shepherd’s a beautiful young lady or a grumpy old man) is very serious for the shepherd and the predator in question.

It is no secret that in the predator world, the sheep is considered to be the perfect prey animal.  Since domesticated sheep are pretty much defenseless, they can’t fight back or even run very fast, like cattle or horses (although they are faster than a great number of people that I know, they’re not going to win any marathons against coyotes, wolves, or anything else).  Plus, they are usually pretty loud, their vocalizations acting like beacons or dinner bells to the predators.  And the sheep’s flocking behavior, while usually a benefit, helps the predators out as well.  With this and their flight behavior, they would over-stimulate the predator’s hunting behavior to the point that the predator would kill more than it needs (11). I have known people who lost a whole flock of sheep (around 100 or so) to a coyote or a cougar in one night or one hour!  Along with that, there is an interesting trait in the Merino, in that when it gets tired of running (even from danger), the sheep will just simply fall over and give up, leaving the predators an easy meal.

There are even studies that have shown that predators who have had no experience with sheep beforehand, would instantly go after sheep and become frequent sheep hunters.  This is proven by the fact that there were coyotes that started hunting sheep after seeing one for the very first. Dingoes, who had hunted nothing but lizards and kangaroos for centuries were able to quickly incorporate sheep to their diet when British settlers arrived in Australia with their livestock.

History

For as long as mankind has domesticated sheep, about 10,000 years, they have had to protect their precious animals from large predators.  In the Middle East, where it is said that the domestication of sheep first took place (20), the shepherds had to protect their sheep from jackals, lions, wolves, striped hyenas, bears, ravens, and eagles.  The bible talks about how the Lord is my shepherd and that one shepherd would even became a king to his people (that shepherd being David).  Then, when the Roman Empire came into the picture, the usage of sheep spread throughout the empire, from Spain to Germany to England. In all those lands, the sheep were preyed upon by European predators; bears, wolves, lynx, golden eagles, etc.  Then, when Europeans colonized throughout the world, their sheep had to deal with both familiar and unfamiliar faces (jaguars, cougars, pythons, and even a parrot called the Kea) that their shepherds had to protect them from.  During this time, people had to (or felt that they had to) resort to lethal methods.  These methods include shooting predators on sight or trappings (both of which could be increased by government bounties), hunting seasons, and poisonings.

Current Affairs

The usage of lethal methods for predator control has been gone almost un-challenged for generations.  But in the late 20^th century, the idea of lethal predator control within the general public started shifting.  While there were a great number of people who were still bitter towards predators (most of them being farmers and ranchers), the majority of people (mostly from cities) were against the usage of lethal methods against predators and called for their protection.  This caused heated debates and even fights between those for predators and those against predators.  Many animal rights groups would point out that these various methods of lethal predator control (such as trapping) were considered to be inhumane and unethical towards the wild hunters.

One such example of this sort of ordeal is when wolves were reintroduced into Yellowstone National Park in 1995.  While the presence of the wolves has been beneficial for the park’s ecology (prey control, coyote suppression, etc.) (16), this had put farmers and ranchers on edge, knowing that any wolves that come out of the park might go after their livestock (especially the sheep) (19).  And with any wolf outside of the park not being protected, hunters, farmers, and ranchers can hunt and shoot the wolves, making the pro-wolf groups upset.  Even though the wolves were taken off of the Endangered Species list in 2009, the debate between the two groups still goes on.

Ranchers protesting to the reintroduction of wolves in the early 90s.

(Citizendium)

Speaking of the Endangered Species list, there are also calls for conservation for the predators of the sheep, since some of them are being threatened with extinction or are just recovering from extinction.  These species would include wolves (different subspecies are threatened or endangered, such as red wolves or Mexican gray wolves), cheetahs, and the kea (it’s technically classified as Vulnerable, but all the same).
.

Why Predator Control?

With all that covered, why must we control predation on sheep?  Well, as it has been mentioned earlier, unlike horses or cattle, sheep are pretty much defenseless against predators and are not able to defend themselves against any sort predator. And once the predators learn of this, they continue to prey upon the sheep for an easy meal, like going to buy a one dollar cheeseburger instead of the 15 dollar T-bone steak.

Another reason to control predation is simple economics.  Due to the sheep’s defenseless nature and how easy they can be killed by predators, it is very easy for a shepherd to lose a great amount of sheep, which means they would lose a great deal of money.  In a 1999 study, it was shown that the United States of America had lost sheep and lambs to predation that were valued at $16.5 million (5).  In that same year and study, the US economy lost $28.97 million dollars to predation on sheep.  And as sheep experts would know, that means you would lose a great deal of lamb chops, wool, sheepskins, and “mowing services” (as in grazing to reduce the spread of noxious weeds and the occurrence of wild fires), and other products or services that sheep give us.

Along with the economic effects of sheep predation, there are also ecological effects.  In continued predations on sheep, this can teach predators “bad manners”, if you will.  With the sheep being an easy supply of food, this could lead the predators to become more dependent on sheep (almost like an addiction), like how there are bears that are becoming more dependent on trash (14).  And with these predators being more dependent on helpless fluffy meat bags, they would also decrease their attention on the wildlife they would normally hunt.  This could lead to an array of ecological consequences, overpopulations of their natural food source being among them.

But Why Non-Lethal

While it is definitely important to apply predation control on sheep, it is perhaps wise to apply nonlethal methods and not just to make some animal rights groups or Fish and Wildlife officers happy.

One such reason is that there are times when lethal methods would actually make things worse for both the farmer and the environment.  There have been studies that show that hunting wolves can disrupt the social structure of packs (15).  This might disrupt the wolf packs to the point that they would become more dependent on sheep and other livestock meat.  It can also significantly disrupt ecosystems.  Destroying the apex predators, who are at the very top of the food chain and the usual sheep hunter, would cause the ecosystem of any environment to collapse, due to the prey species being overpopulated and those populations no longer exhibiting any “eco-friendly” habits and behaviors (8).

There were also cases when the wrong species would be targeted, unintentionally or otherwise.  For example, when the lynx was about to be reintroduced to the Rocky Mountains of Colorado, many farmers were worried that the lynx would prey on their sheep (as there are some populations of lynx that did predate on whole flocks of sheep around the world) (12).  But when the lynx were reintroduced to the Rockies and studied closely and carefully, it was realized that these lynx would rather predate on Thumper (snowshoe hares) instead of Little Bo Peep’s lambs.  In California, ranchers once poisoned livestock carcasses in order to control coyote populations, only to contribute to poisoning turkey vultures and almost wiping out the Californian condor (17). 

Speaking of species being destroyed, there are species that do predate on sheep that are already in a terrible threat of becoming extinct.  In Africa, the cheetah is suffering and classified as Vulnerable, due to habitat destruction, illegal pet trade, high mortality rates, and severe inbreeding.  But it is made worse when they are hunted by farmers due to the cheetahs preying on their sheep.  The Mexican Gray wolves and red wolves are subspecies of wolves that are just recovering from almost being eradicated by farmers and ranchers to protect their livestock.  While reintroductions have already been made, it is essential to get nonlethal predation control methods that are greatly effective.  And the Kea is classified as Vulnerable as well and with its habit of killing sheep, it doesn’t make it a popular animal with the local farmers and ranchers.

The examples expressed earlier of why we need to go for non-lethal methods on predator control are no doubt troublesome for wild animals and even to us.  Yet these animals have actually gotten off easy compared to one species that was the target of lethal predator control methods so harsh and so wrong that it has actually been wiped out for biased and unreasonable motives.

An Individual from the London Zoo in the late 19th Century

This species of predator that is native to the island of Tasmania (the island where the Tasmanian devil, the inspiration for the cartoon character Taz, comes from) is about the same size and weight of a border collie.  At first glance, it looks a bit like a dog, but you will see some differences.  It has a stiff tail (unlike the flexible tail of the dog) and possesses stripes (like a tiger) from the middle of its back to the base of its tail.  When it yawns, it opens its mouth much wider than any dog could and instead of panting, it makes a raspy breathing sound that would make one that it is sick.  What is more surprising about this creature is that it is not a canine or a cat. It is actually more related to Skippy the kangaroo than it is to Fido or Shere Khan, meaning that it is a marsupial (the offspring is raised in a pouch).  This creature is called the Tasmanian tiger, Tasmanian wolf, or the Thylacine.

While this creature seems wonderful and beautiful to our modern eyes, it was sadly seen as an inferior, uninteresting, and vile beast in the past.  When its island home was colonized by the British settlers, carcasses of their prized Merino sheep were discovered in the country side, ripped apart.  Instantly, the settlers blamed the thylacine for these terrible deeds and even accused it of being a vampiric beast (1).  With this pressure from the farmers, the Tasmanian government put up a bounty of one British pound on the thylacine’s head in 1830.  This continued until the last wild thylacine was shot in 1930.  After that, the last thylacine, a female called Ben, died at the Hobart Zoo (in Tasmania) on the seventh of September, 1936.  There had been attempts to save the species, but the bias of it being a notorious sheep killer was so strong that only one thylacine enjoyed full legal protection as an endangered species for its last 59 days and that was Ben (13).

Footage of the Last Thylacine, a female named Ben from the 1930s

(from Youtube)

Ironically, in recent years, it has been proven that, with the exception of a couple individuals, there is no evidence that the thylacine ever killed any sheep at all (1).  This was proven in that the jaws wouldn’t be affective against the adult sheep’s bones (13).  And it was even shown that it was not a vampiric creature of any sort.  It was later found that the ‘reports’ of thylacines killing off sheep were made by influential landowners who were known for being terrible with animal husbandry, and by farm hands that were ex-cons and didn’t know how to properly take care of sheep and lied in order to keep their jobs.  And for times when sheep were actually killed?  It was found out that it was feral dogs that ripped sheep apart or killed whole flocks.  So, it appears that we have lost a beautiful and interesting animal because of ignorant biases and our habit of shooting first and asking questions later, or never.  We must not let history repeat itself and we must get it right this time.

Some Non-Lethal Methods

Now that we have gotten into the reasons for using non-lethal methods, let’s present some nonlethal methods on controlling predation on sheep, shall we?

One such non-lethal method in predation control is a pretty simple and basic one, which is fences.  The most common fencing that is used for predation control, because of price and effectiveness, is broad fencing and electrified fencing (or, as I like to call it, hot wire).  Broad fences are effective because unlike barbed wire fences, they prevent both predators and sheep from going through the fence.  Electrified fences are effective because, obviously, no predator would like to get shocked and when they do get shocked when predating on sheep, it would make them think twice about going after sheep again (basically, it’s like a shock collar for predators).  Along with that, fencing would generally keep the sheep in the desired locations, safe from predators.

But there are some drawbacks to using fencing as predation control.  One would be that all fences, especially the electrified fence, would need to receive maintenance every now and then so they don’t fall apart.  And while fencing will stop some predators, it doesn’t stop all of them.  Eagles can fly over fences pretty effectively.  Although, on an added note, you could prevent this a bit by applying reflective material on top of the fences to repel the birds of prey (like it has been done for reintroducing black-footed ferrets) (2).  Also, fencing would restrict the grazing of the sheep, which would lead to overgrazing and soil erosion (unless rotational grazing is used).

Perhaps the most famous example of the effectiveness and usage of predator-proof fences is the legendary Dingo Fence of the Australian outback.  This grand fence stretches to a length of 3,488 miles long (5,614 kilometers), making it somewhat of a rival to the Great Wall of China and can be seen from space.  Perhaps the most ironic thing about this fence is that its original purpose was not to protect the sheep from the dingo, but it was intended to protect their pastures from the invading European rabbit.  But since the rabbits could dig under the fences and it effectively restricted the movement of the dingo, the fence was repurposed for the dingo.  This has proven successful since the numbers of dingoes on the sheep side of the fence is counted from few to none (for any dingo found on that side is instantly shot and “scalped” for a bounty reward of a few Australian dollars) and the population of emus, kangaroos, and rabbits are higher on the sheep side than the dingo side (7).

A small part of the Dingo Fence (Wiki)

Another non-lethal (most of the time) method of controlling sheep predation is the usage of guard animals.  While the usage of guard animals to protect sheep is not new, it has been gaining popularity through recent years.  The species of guard animals vary, including sheep dogs, llamas, donkeys, and even a breed of goat called the fainting goat.  With the case of sheep dogs, llamas, and donkeys, they protect the sheep by literally protecting them from predators.  How the fainting goat “protect” sheep is a bit cruel.  This is because when fainting goats get startled or scared, they produce a type of acid that literally locks up their legs, making them fall over and seem like they have fainted.  When they do this, the predators would consume them, while the sheep run to safety.  This was a common practice in the past, but it’s not done now (this would teach the predators bad habits anyway).

Donkeys are effective guard animals, when they have a companion.

(Whole Home News)

As mentioned earlier, these guard animals would protect the sheep, due to them seeing sheep as a member of their herd or pack.  They would always be on guard, vigilant, and would be ready to fight off any animal (or person) that appeared to be a threat to their flock.  With their protective instinct and fighting will, they can prevent sheep predation.  This was proven when Anatolian shepherds were used in Africa to protect sheep from cheetahs (9).  The experiment that started this was a success and it has become more common place, lowering the amount of sheep killed by cheetahs and the chances of them being hunted by farmers.

But even this is not the silver bullet of predation control.  Just as with any animal, there will be times when the guard animal becomes sick or dies, leaving the sheep in the open.  While the species mentioned can be great guard animals, there will be individuals that do not like sheep and will not become guard animals for the flock in question.  In the case of donkeys and llamas, the guard animals will need a companion to be more effective in protecting the herd or to even be in the mood to protect the herd.  Along with that, not one species would be effective against all predators.  For example, llamas won’t work against wolves, and even larger breeds of guard dogs need more companions to protect their folks from larger predators, such as wolves and bears. However, it might be possible to use mules as guard animals, because I have seen mules take on a mountain lion by themselves and actually kill it.

Another form of non-lethal predation control that could be used is interspecific grazing.  What it means is to have sheep graze alongside larger species of livestock that can protect themselves, such as horses and cattle.  While these animals would probably not provide direct protection for the sheep, the presence of much larger animals would deter predators from attacking most of the time.  This works even more efficiently if you have taught the larger livestock how to defend themselves against predators (18).  Along with predation control, this could provide several other great opportunities.  One is an ecological opportunity, in that with the horses or cattle consuming the course grasses and exposing the high-quality plants (that are unpalatable to them), it would provide sheep a high quality grazing (that considers these plants to be palatable), like the grazers in Africa (10).  This could also be a market opportunity, in that you can gain more money from marketing on both the cattle and sheep industry, rather than just doing one or the other.  Also, this could be a sort of symbolic way of showing that the Range Wars (the wild western war between sheep and cattle herders) are finally over.

When are Lethal Methods Exceptional?

But, like in anything, there are times when lethal methods are necessary.  Such as when a particular individual is confirmed to be the actual sheep killer.  This could be proven or disproven by analyzing the predator’s scat or dung, to see if the predator did in fact eat sheep continuously (by looking for wool in the dung or testing the scat for the DNA of any species of animal that predator has eaten).  Another way would be to do an isotopic analysis.  How this works is that when an animal eat something, the isotopic signature of that foodstuffs is stuck on the animal’s tissues.  When herbivores eat plants, they get the isotopic signatures into their tissue and when the predators eat the herbivores, those same isotopic signatures are bonded to the predator’s tissues as well.  By doing this, you can tell if this particular predator has been eating sheep or not.  There is also the usage of radio or GPS tracking collars.  With these, you can tell where the animal has be and what it has been doing.  If it has been staying close to human homes, farms, and ranches at the exact same time and places where the people have reported losing sheep to predation, then it would stand to reason that individual or individuals are actively hunting sheep and they need to be taken care of.

A non-lethal predator control method that I had failed to mention earlier is relocation.  If an individual predator or a group of predators are livestock killers, but are important for conservation purposes (e.g. genetics), they would be relocated to a different area, away from where they have been killing sheep.  Sometimes this works, but there are times when they are able to find their way back to their old territory and continue hunting sheep.  This can happen due to the animals knowing their way around the land pretty well or the presence of other predators who see the relocated animal or animals as a threat and chase them off of their territory (6).

With this in mind, I would propose a possible way of fixing this problem; I call it the “Relocation Switcheroo”.  Basically, you would take a sheep-killing predator and another predator who is known to avoid sheep (or is conditioned to dislike sheep, like how tiger quolls were taught to dislike cane toads (4)) and you would have them switch territories.  By doing this, you would be able to get rid of the problem predator without killing it or disrupting the ecosystem.  But in order for this to work, you keep to find a non-problem individual who has a territory far away from the area where the problem predator is killing sheep, is around the same age and size as the problem predator (to prevent them for being intimated with the other’s territorial scents), and is known for not hunting sheep or is conditioned to dislike sheep.  When you’ve taken these two animals away from their old territories and into their new ones, you have to keep them in a fence paddock that is a couple acres in size so that they can get accustomed to the area, and with the problem individual, have him feast on the small wildlife in the area and some culled deer to require a taste for wild meat again.  After perhaps a week or so, release the individuals out of their acclimatizing areas and keep track on both of them.  If they are doing well and not causing problems, let them be.  If they are causing problems, then put them down (due to it probably being too expensive to redo this whole thing again).

Conclusion

With all this talk about predation control on sheep and its effects, you are perhaps wondering why we should care about all this.  Why should we care whether sheep are being consumed by predators or not?  Why should we care how predators that hunt sheep are being taken care of?  Why should we care how the predators’ ecosystems are effected by predation control or just hunting sheep?  I say that it is because we are students of animal husbandry, which intends for us to take care of the well-being of our animals.

In the case of our sheep, we have selectively bred them to become entirely dependent on humans for their health, well-being, and their safety.  For if our sheep had not been protected by predation, they would not be able to give us what we want and what we need, whether it is meat, milk, skins, wool, or grazing.  As Temple Grandin would tell us, livestock that feel calm and safe (and are safe) will do better, provide more, and be more profitable for us (3).

For the ecosystem and predators, the predators help make sure that the natural world’s ecosystem is healthy. And when the ecosystem is healthy, it is able to provide us with the resources that we need for our survival and comfort.  It would be wise to not repeat the mistakes made in the past, such as with our thylacine ordeal.  The wildlife supports the natural world and livestock supports the human world, so in order for both worlds to coexist peacefully, both need to be supported properly.  So, while predation control is not the sole solution for this to happen, it is a part of the solution.

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