A new role for livestock guard dogs
Livestock guard dogs, traditionally used to protect farm animals from predators, are now being used to protect the predators themselves
A
AAlongside shepherds, dogs bred to guard livestock have for millennia kept flocks of sheep and goats, and herds of cattle, safe from wolves, bears and other predators. That role largely vanished during the nineteenth and twentieth centuries: once these predators had been hunted almost to extinction, there was little for the dogs to do. The picture has shifted lately. Conservation measures have let predator populations recover and spread once more, so that livestock is again at risk and the guard dog, somewhat unexpectedly, is back in demand.
B
BRoughly fifty breeds are at work as guard dogs around the globe. From when it is very young, each dog is reared among the very animals it will later watch over, until the flock or herd effectively becomes its family. Faced with danger, the dog puts itself between the threat and the livestock and barks fiercely; driving an intruder off is always possible, yet often it never comes to that, because simply being present is enough. Tomas Vidal, a shepherd who keeps four such dogs, explains that the first lessons all aim to make the animal grasp that its entire existence will revolve around the livestock. 'A fluffy white pup makes lovely company,' he says, 'but lavish too much affection on it and what you have is a fine guardian for your porch, not for your sheep.'
C
CJust how well the dogs perform is borne out by research. In Spain, the biologist Nuria Bassols surveyed farmers enrolled in a scheme that trains guard dogs to defend herds against wolves, and found that over 90 per cent rated the dogs' work as very good or excellent. A separate New Zealand study, led by Rebecca Hale and a colleague at the University of Otago, reached comparable figures: among herders questioned, more than 65 per cent said losses to predators had ceased altogether once the dogs arrived, while nearly all the rest recorded fewer attacks. Handled and deployed properly, Hale maintains, no rival method comes close; judged by how much stock is kept from predators, the guard dog is simply the most effective control available.
D
DThere is, though, a further and newer purpose these dogs serve: safeguarding the predators themselves. The thinking runs that if fewer animals are lost, farmers grow less hostile towards predators and less inclined to kill them. Consider Kenya, where upwards of 90 per cent of the nation's leopards range beyond the edges of protected reserves, in the districts where people keep livestock. Held to blame for the resulting losses, the cats have been destroyed by farmers in considerable numbers. Once guard dogs were brought in, however, more than nine farmers in ten described a steep drop in their livestock losses and said they had accordingly grown less willing to kill predators. To Karl Reinholt, of the University of Alberta in Canada, the lesson applies far more broadly. 'The interests of livestock keepers and those of conservationists actually coincide,' he says. 'A rancher whose cattle are still alive is not a rancher telephoning for a licence to shoot a wolf.'
E
EWeighing up the published studies as a whole, Eleanor Pike of the University of Galway in Ireland observed that as many as 88 per cent of farmers claimed to have stopped killing predators once they kept dogs, but she cautioned that figures people give about their own conduct ought to be treated sceptically. There is, besides, a chance that guard dogs merely push predators onto neighbouring land lacking such protection, where whatever becomes of them goes unrecorded. Bassols presses the same point: in some districts nearly every farmer joins in, she notes, whereas elsewhere only a handful keep dogs. 'Where the coverage is not total, the pressure from wolves is merely shifted onto a neighbour's herd, and that neighbour may lay down poison and destroy an entire pack.'
F
FA distinct worry is that guard dogs might carry ecological side effects nobody intended. Research hints that sparing one sort of predator can rebound badly on other species, and though the scale of this remains uncertain, Kenya supplies a clear illustration. Leopards are not the only creatures preying on the country's sheep and goats; several other predators do so too. Reporting in 2016, scientists found that even as the appearance of guard dogs eased the pressure on leopards, the tally of hyenas killed by dogs and farmers actually climbed. The dogs leave further ecological marks as well. They have been known to pass parasites to wild populations, among them the endangered African wild dog, and they can end up competing with rival carnivores for prey. Their very presence, what is more, creates a 'landscape of fear' able to alter the way prey animals behave.
G
GSo far, even so, the evidence also shows that such outcomes need not always be harmful. Guard dogs can bring advantages nobody foresaw, shielding defenceless wildlife from other predators. Ground-nesting birds out in open fields, whose eggs and chicks stoats would otherwise plunder, have been found to do better where the dogs are around. In New Zealand, indeed, researchers are now deliberately putting them to work to lift biodiversity and carve out safe havens for species predation would otherwise endanger. Get the approach right, then, and the guard dog may yet have a promising part in helping people and wildlife share the same ground.
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Question 1 - 5
Which paragraph contains the following information?
A
B
C
D
E
F
G
1.
a warning that farmers' descriptions of their own behaviour may not be reliable
2.
an example of a predator species that has been safeguarded thanks to guard dogs
3.
an assertion that, handled well, guard dogs outperform every alternative method
4.
an account of how the dogs can ward off danger to a herd without fighting
5.
an upbeat view of future relations between people and wild animals