IELTS CAM Inspired 20 - Reading Test 4 with Practice Test, Answers And Explanation
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IELTS Mock Test 20 - Reading Test 4 With Practice Test, Answers And Explanation
Passage
❓ Câu hỏi passage 1
Question 1 - 7
Complete the notes below.
Choose ONE WORD ONLY from the passage for each answer.
The life and work of Georgia O'Keeffe
• after her training, she earned a living for several years as a
1.
, working in schools across a number of American states
• her early experimental drawings, made in
2.
, were put on display in New York
• once settled in New York, her reputation rested on canvases showing the
3.
that span the city
• she painted a groundbreaking set of greatly enlarged studies of
4.
• on reaching Arizona, her earliest subjects were the many
5.
lying about the landscape
• for more than four decades she went on depicting the individual elements that made up the striking
6.
of Arizona
• toward the end of her career, her many flights by aeroplane led her to paint, from high above, both clouds and
7.
Question 8 - 13
Do the following statements agree with the information given in the Reading Passage?
TRUE if the statement agrees with the information
FALSE if the statement contradicts the information
NOT GIVEN if there is no information on this
8
Throughout her long career, the various movements that rose and fell in the art world had little effect on the way O'Keeffe painted.
9
O'Keeffe did not decide to pursue painting as a career until after she had completed her college studies.
10
O'Keeffe and Meier met for the first time at the exhibition of her drawings.
11
Over a period lasting about two decades, O'Keeffe repeatedly sat for photographs taken by Meier.
12
The house O'Keeffe lived in during the winter was the one set beneath the tall cliffs.
13
During the closing years of her life, O'Keeffe's pictures were selling for large sums of money.
Passage
❓ Câu hỏi passage 2
Question 14 - 17
Reading Passage 2 has six paragraphs, A-F.
Which paragraph contains the following information?
Write the correct letter, A-F.
14
the way one kind of plant life gives a coast a natural defence against the sea
15
an estimate of how many years may pass before a warming climate’s effects begin to ease
16
a remark that a particular solution is unusually inexpensive
17
the use of a tool for pinpointing the places where action is most urgently needed
Question 18 - 22
Complete the sentences below.
Choose ONE WORD ONLY from the passage for each answer.
18
In Vallreza, roads short of trees were surfaced with a pale
that bounces back sunlight.
19
In the Sundal delta, a not-for-profit organisation has produced homes able to
when the water rises.
20
In Meharra, the encroaching sea has driven growers to cultivate
that cope with briny soil rather than the grains raised there before.
21
As part of overhauling its stormwater system, Port Aldis has fitted high-capacity
to move great volumes of water.
22
The first step toward helping Larang’s mangroves recover was the building of
.
Question 23 - 26
Match each statement with the correct person, A-E.
List of Findings
A
Mateo Rell
B
Helena Vos
C
Farah Idris
D
Lucia Herrera
E
Bram Okonkwo
23
Plans need to actively bring in and benefit the people who live in the affected area.
24
Here, taking the heat out of the environment is nothing less than a matter of staying alive.
25
In the decades ahead, still more effort will be required to keep pace with the advancing sea.
26
The tally of places needing defence against floods has climbed of late.
Passage
❓ Câu hỏi passage 3
Question 27 - 31
Reading Passage 3 has seven paragraphs, A-G.
Which paragraph contains the following information?
Write the correct letter, A-G.
27
a warning that farmers' descriptions of their own behaviour may not be reliable
28
an example of a predator species that has been safeguarded thanks to guard dogs
29
an assertion that, handled well, guard dogs outperform every alternative method
30
an account of how the dogs can ward off danger to a herd without fighting
31
an upbeat view of future relations between people and wild animals
Question 32 - 36
Match each statement with the correct person, A-E.
List of Findings
A
Nuria Bassols
B
Rebecca Hale
C
Eleanor Pike
D
Karl Reinholt
E
Tomas Vidal
32
Guard dogs, used correctly, are unmatched at keeping farm animals safe.
33
People's own reports of how their behaviour has changed should be viewed with caution.
34
Training a livestock guardian calls for a different emphasis from training a dog to guard a home.
35
Protecting herds with dogs can benefit wild creatures as much as the livestock.
36
Unless most farms in an area take part, the approach may do harm elsewhere.
Question 37 - 40
Complete the summary below.
Choose ONE WORD ONLY from the passage for each answer.
Unintended ecological effects of using guard dogs
In Kenya, guard dogs have been brought in to keep livestock safe from leopards. One result has been a rise in the killing of rival predators, above all . The dogs are also thought capable of passing to wildlife, potentially harming additional species, and of leaving less for certain wild animals to hunt. On the positive side, by guarding birds' nests the dogs may shield them from raiders such as .
DOL IELTS Đình Lực
21/10/2026
📖 Bài đọc passage 1
Georgia O'Keeffe
Across some seventy years, the American painter Georgia O'Keeffe (1884-1981) ranked among her country's most prominent artists. What set her apart was a refusal to follow whichever style was in fashion; she held instead to a personal aim - to draw out the underlying, abstract shapes hidden within nature. A sharp eye and a delicate command of the brush let her capture the faint gradations of hue, form and light that gave her canvases their vitality and won a wide following.
O'Keeffe was born in 1884 on a farm near Cedar Falls, Iowa, where her parents, Walter and Cora, were grain merchants; she grew up among four brothers and sisters. She had settled on a future in art by 1902, the year she left high school. Formal training in conventional painting followed, first at the Lakeside Academy of Art in Chicago in 1902 and then at the Manhattan Art League from 1904 to 1906. Once her studies were over, she spent some years as a drawing tutor, giving classes at institutions across Ohio, Kansas and Georgia from 1908 until 1917.
In these years O'Keeffe began to try abstract work, using ink for a run of strikingly original drawings that pushed her painting onto fresh ground. A friend in New York, to whom she posted several of these sheets, passed them in January 1915 to Conrad Meier, a photographer who also dealt in art. Taken with what he saw, Meier put them on show later that year at his gallery on Madison Avenue, where American audiences were regularly shown the newest work of experimental painters and photographers.
Encouraged by Meier and assured of his financial backing, O'Keeffe settled in New York in the summer of 1917 to make her living from painting. Over the following three decades he championed her tirelessly, mounting twenty solo shows alongside many group displays. Marriage came in 1923. All that passed between them, in private life and in work alike, is preserved in the acclaimed black-and-white portraits Meier made of her across roughly twenty years, from 1916 to 1936.
By the mid-1920s her standing was secure: critics counted her among the country's leading and most successful painters, and the public linked her above all with bold architectural canvases in which the great bridges of New York loom. Yet her brush turned most often to subjects drawn from nature, a habit fed by the summers she spent each year at the Meier family's country house. From 1923 she painted leaves at such magnified scale that the viewer seems pulled right inside the image.
Blown up until a single tiny detail spanned a canvas a full metre across, these forms had their contours thrown into relief and took on an almost abstract character. Compositions this bold did much to cement her name as a modernist of real originality.
O'Keeffe's first lengthy stay in the desert of Arizona came in 1928. The trip marked her deeply and reshaped her painting almost at once. For the twenty years that followed she returned most summers, staying up to six months and working largely alone, before returning to New York each winter to show the fresh canvases at Meier's gallery. Only when she moved to Arizona for good, in 1948, did the routine end.
In that setting fresh ideas came to her. What caught her eye first were the countless sun-bleached antlers scattered across the rough Arizona country. Among the earliest of her Southwestern works, and still the most admired, are two that render the worn surface, broken edges and ragged hollows of an elk skull. She returned to this ground later in a sequence she called the Hollow Forms pictures, preoccupied with the play between rounded and hollowed surfaces and between solid mass and open space. Yet what truly gripped her, for more than forty years, was the region's magnificent scenery - its strange rock formations, intense colour, clear light and unfamiliar plant life. Again and again she set down the boulders, cliffs and peaks in close-up, just as she had once treated the leaves and stems of her nature studies.
In time she came to keep two houses in Arizona. One, a summer retreat she named Coyote Springs, sat directly below cliffs rising some 200 metres; the other, where she passed the winters, stood in the little town of Redstone. Both gave her ample material, but it was a single feature of the Redstone house - its broad walled courtyard, entered through a dark door - that stirred her most. Across more than thirty canvases painted between 1945 and 1959, she remade that courtyard as an abstract arrangement of geometric forms.
Between the 1950s and the 1970s O'Keeffe became a great traveller, journeying to Asia, the Middle East and Europe. Air travel gave rise to her final pair of important series: seen from above, coastlines formed the subject of one; the other gathered sweeping views of the sky from just over the clouds. For both she worked on an enlarged scale, at times as big as a mural - perhaps mirroring her widened view of the world. Carrying one cloud design onto a vast canvas six metres long, achieved in 1964 with assistants, was a formidable feat, the more so for a painter approaching eighty.
Her final twenty years or so yielded comparatively little, as failing eyesight and poor health increasingly stood between her and her work. She died in 1981, aged ninety-seven. Even so, the some 850 paintings she left behind have gone on drawing later generations of artists and admirers, who still find inspiration in these unmistakably American pictures.
A. Across the globe, countries are no longer merely bracing for climate change; they are already adjusting to the disruption it brings. The carbon dioxide given off since the industrial era has, in effect, locked in decades of change: even a complete halt to emissions tomorrow would spare us nothing, and researchers estimate the planet would keep warming for roughly fifty more years regardless. Throughout that time glaciers would go on shrinking and the seas would keep rising. Because the weight of these shifts falls far more heavily on some regions than others, it is in the worst-affected places that inventive solutions are taking root.
B
In the heat-battered city of Vallreza, in southern Spain, Mateo Rell runs the municipal heat-resilience unit and oversees a cluster of trial schemes gathered under the name Keeping Vallreza Cool. These range from lining the avenues with freshly planted trees to laying down a specially devised cool-surface treatment, all serving the council's aim of lowering the city's average temperature by 2°C. For somewhere like Vallreza, Rell says, drawing the heat out of the streets comes down plainly to a question of survival. To decide where to begin, the scheme leaned on a satellite-linked geospatial mapping platform that singled out the avenues with the thinnest tree cover across four districts; those roads were then treated with a pale, light-reflecting coating already shown to pull local road-surface temperatures down by 7°C. One of them, in the Almeda district, now stands out when viewed from orbit as a lone cool strip against a heat map that glows red everywhere else.
C
One October, when the yearly floods spread across the Sundal rice plains, five modest homes refused to stay grounded and lifted gently as the water climbed. Houses in this low delta have always stood on stilts, but these few had been engineered to float outright. Behind the redesign was the Floating Homestead Initiative, a not-for-profit that since 2004 has studied and refitted buildings to let them ride out flooding. Hardly anyone was speaking about a shifting climate when the work began, recalls its founder, Dr Helena Vos, yet what her team does is now called for in places that had no use for it before. Making a house buoyant, she notes, runs to only about a quarter of what wholly replacing its foundations would cost, and it dodges the added wind danger that a taller, raised building invites. There is a further gain: a floating home can be adjusted with real sensitivity to local custom, made to echo the dwellings a community already lives in.
D
Nowhere is more at the mercy of a warming world than the low delta country of Meharra, most of whose land rests barely a metre above the waves while some three-quarters of it sits on floodplains. Along Meharra's coast, notes Farah Idris of the relief group Delta Futures Trust, roughly 28 million people already wrestle with salt working into their soil and water. One initiative, rather than battling the salt, is showing coastal villages how to live alongside it. Eight thousand farmers have joined the Trust in taking up salt-tolerant vegetables such as carrot, potato, cabbage and beetroot, all of which handle briny ground far better than the rice and wheat that has long been the norm. The contrast, Idris says, leaps out at anyone who looks: on one side a lifeless, barren field, on the other the flourishing green plot where her team has laboured beside the growers. Those who have picked up these saline-farming methods now report two or three extra harvests a year.
E
On the low island city of Port Aldis, the sea does more than press against the walls along the shore; it wells up through the ground beneath the streets, so the town's one genuine defence is to raise itself higher. Where the land lies lowest and most exposed, the work began first, with roadways built up by as much as half a metre. All of this forms part of a costly but unavoidable reworking of how Port Aldis handles its stormwater. To the raised roads the authorities have added high-capacity new pumps, each able to move as much as 90,000 litres of water a minute. Measures like these are far too readily forgotten once a flood has passed, warns Lucia Herrera, the city's senior resilience coordinator, who is nonetheless sure they cannot be done without and that the task is far from complete. Two, three or four decades from now, she says, they will simply have to return and adapt once more to conditions that never stop changing.
F
For many coastal settlements a sea wall is the obvious answer, yet along the soft, silt-laden northern coast of Larang such walls give way time and again, only deepening the erosion they were built to halt. The mangroves of that coast have been the target of one restoration attempt after another; these are tangled stands of trees and shrubs whose dense, mesh-like roots guard the shore by catching sediment, lifting the seabed and draining the strength from waves and tides. According to Bram Okonkwo of the Coastal Wetlands Alliance, most such replanting drives, popular though they are, come to nothing. His organisation opted instead for another route, erecting semi-permeable barriers of bamboo and brushwood that stand in for mangrove roots and coax the trees into re-establishing themselves unaided. Success has been modest, and greatest where the ground is subsiding least. The weakness of conventional infrastructure, Okonkwo argues, is its habit of chasing one fix at a time; lasting results demand a move toward many-sided methods that fold in natural processes while drawing in and rewarding the communities and local decision-makers on the ground.
Livestock guard dogs, traditionally used to protect farm animals from predators, are now being used to protect the predators themselves
A
A. Alongside 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
Roughly 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
Just 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
There 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
Weighing 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
A 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
So 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.
Across some seventy years, the American painter Georgia O'Keeffe (1884-1981) ranked among her country's most prominent artists. What set her apart was a refusal to follow whichever style was in fashion; she held instead to a personal aim - to draw out the underlying, abstract shapes hidden within nature. A sharp eye and a delicate command of the brush let her capture the faint gradations of hue, form and light that gave her canvases their vitality and won a wide following.
O'Keeffe was born in 1884 on a farm near Cedar Falls, Iowa, where her parents, Walter and Cora, were grain merchants; she grew up among four brothers and sisters. She had settled on a future in art by 1902, the year she left high school. Formal training in conventional painting followed, first at the Lakeside Academy of Art in Chicago in 1902 and then at the Manhattan Art League from 1904 to 1906. Once her studies were over, she spent some years as a drawing tutor, giving classes at institutions across Ohio, Kansas and Georgia from 1908 until 1917.
In these years O'Keeffe began to try abstract work, using ink for a run of strikingly original drawings that pushed her painting onto fresh ground. A friend in New York, to whom she posted several of these sheets, passed them in January 1915 to Conrad Meier, a photographer who also dealt in art. Taken with what he saw, Meier put them on show later that year at his gallery on Madison Avenue, where American audiences were regularly shown the newest work of experimental painters and photographers.
Encouraged by Meier and assured of his financial backing, O'Keeffe settled in New York in the summer of 1917 to make her living from painting. Over the following three decades he championed her tirelessly, mounting twenty solo shows alongside many group displays. Marriage came in 1923. All that passed between them, in private life and in work alike, is preserved in the acclaimed black-and-white portraits Meier made of her across roughly twenty years, from 1916 to 1936.
By the mid-1920s her standing was secure: critics counted her among the country's leading and most successful painters, and the public linked her above all with bold architectural canvases in which the great bridges of New York loom. Yet her brush turned most often to subjects drawn from nature, a habit fed by the summers she spent each year at the Meier family's country house. From 1923 she painted leaves at such magnified scale that the viewer seems pulled right inside the image.
Blown up until a single tiny detail spanned a canvas a full metre across, these forms had their contours thrown into relief and took on an almost abstract character. Compositions this bold did much to cement her name as a modernist of real originality.
O'Keeffe's first lengthy stay in the desert of Arizona came in 1928. The trip marked her deeply and reshaped her painting almost at once. For the twenty years that followed she returned most summers, staying up to six months and working largely alone, before returning to New York each winter to show the fresh canvases at Meier's gallery. Only when she moved to Arizona for good, in 1948, did the routine end.
In that setting fresh ideas came to her. What caught her eye first were the countless sun-bleached antlers scattered across the rough Arizona country. Among the earliest of her Southwestern works, and still the most admired, are two that render the worn surface, broken edges and ragged hollows of an elk skull. She returned to this ground later in a sequence she called the Hollow Forms pictures, preoccupied with the play between rounded and hollowed surfaces and between solid mass and open space. Yet what truly gripped her, for more than forty years, was the region's magnificent scenery - its strange rock formations, intense colour, clear light and unfamiliar plant life. Again and again she set down the boulders, cliffs and peaks in close-up, just as she had once treated the leaves and stems of her nature studies.
In time she came to keep two houses in Arizona. One, a summer retreat she named Coyote Springs, sat directly below cliffs rising some 200 metres; the other, where she passed the winters, stood in the little town of Redstone. Both gave her ample material, but it was a single feature of the Redstone house - its broad walled courtyard, entered through a dark door - that stirred her most. Across more than thirty canvases painted between 1945 and 1959, she remade that courtyard as an abstract arrangement of geometric forms.
Between the 1950s and the 1970s O'Keeffe became a great traveller, journeying to Asia, the Middle East and Europe. Air travel gave rise to her final pair of important series: seen from above, coastlines formed the subject of one; the other gathered sweeping views of the sky from just over the clouds. For both she worked on an enlarged scale, at times as big as a mural - perhaps mirroring her widened view of the world. Carrying one cloud design onto a vast canvas six metres long, achieved in 1964 with assistants, was a formidable feat, the more so for a painter approaching eighty.
Her final twenty years or so yielded comparatively little, as failing eyesight and poor health increasingly stood between her and her work. She died in 1981, aged ninety-seven. Even so, the some 850 paintings she left behind have gone on drawing later generations of artists and admirers, who still find inspiration in these unmistakably American pictures.
B. In the heat-battered city of Vallreza, in southern Spain, Mateo Rell runs the municipal heat-resilience unit and oversees a cluster of trial schemes gathered under the name Keeping Vallreza Cool. These range from lining the avenues with freshly planted trees to laying down a specially devised cool-surface treatment, all serving the council's aim of lowering the city's average temperature by 2°C. For somewhere like Vallreza, Rell says, drawing the heat out of the streets comes down plainly to a question of survival. To decide where to begin, the scheme leaned on a satellite-linked geospatial mapping platform that singled out the avenues with the thinnest tree cover across four districts; those roads were then treated with a pale, light-reflecting coating already shown to pull local road-surface temperatures down by 7°C. One of them, in the Almeda district, now stands out when viewed from orbit as a lone cool strip against a heat map that glows red everywhere else.
C. One October, when the yearly floods spread across the Sundal rice plains, five modest homes refused to stay grounded and lifted gently as the water climbed. Houses in this low delta have always stood on stilts, but these few had been engineered to float outright. Behind the redesign was the Floating Homestead Initiative, a not-for-profit that since 2004 has studied and refitted buildings to let them ride out flooding. Hardly anyone was speaking about a shifting climate when the work began, recalls its founder, Dr Helena Vos, yet what her team does is now called for in places that had no use for it before. Making a house buoyant, she notes, runs to only about a quarter of what wholly replacing its foundations would cost, and it dodges the added wind danger that a taller, raised building invites. There is a further gain: a floating home can be adjusted with real sensitivity to local custom, made to echo the dwellings a community already lives in.
D. Nowhere is more at the mercy of a warming world than the low delta country of Meharra, most of whose land rests barely a metre above the waves while some three-quarters of it sits on floodplains. Along Meharra's coast, notes Farah Idris of the relief group Delta Futures Trust, roughly 28 million people already wrestle with salt working into their soil and water. One initiative, rather than battling the salt, is showing coastal villages how to live alongside it. Eight thousand farmers have joined the Trust in taking up salt-tolerant vegetables such as carrot, potato, cabbage and beetroot, all of which handle briny ground far better than the rice and wheat that has long been the norm. The contrast, Idris says, leaps out at anyone who looks: on one side a lifeless, barren field, on the other the flourishing green plot where her team has laboured beside the growers. Those who have picked up these saline-farming methods now report two or three extra harvests a year.
E. On the low island city of Port Aldis, the sea does more than press against the walls along the shore; it wells up through the ground beneath the streets, so the town's one genuine defence is to raise itself higher. Where the land lies lowest and most exposed, the work began first, with roadways built up by as much as half a metre. All of this forms part of a costly but unavoidable reworking of how Port Aldis handles its stormwater. To the raised roads the authorities have added high-capacity new pumps, each able to move as much as 90,000 litres of water a minute. Measures like these are far too readily forgotten once a flood has passed, warns Lucia Herrera, the city's senior resilience coordinator, who is nonetheless sure they cannot be done without and that the task is far from complete. Two, three or four decades from now, she says, they will simply have to return and adapt once more to conditions that never stop changing.
F. For many coastal settlements a sea wall is the obvious answer, yet along the soft, silt-laden northern coast of Larang such walls give way time and again, only deepening the erosion they were built to halt. The mangroves of that coast have been the target of one restoration attempt after another; these are tangled stands of trees and shrubs whose dense, mesh-like roots guard the shore by catching sediment, lifting the seabed and draining the strength from waves and tides. According to Bram Okonkwo of the Coastal Wetlands Alliance, most such replanting drives, popular though they are, come to nothing. His organisation opted instead for another route, erecting semi-permeable barriers of bamboo and brushwood that stand in for mangrove roots and coax the trees into re-establishing themselves unaided. Success has been modest, and greatest where the ground is subsiding least. The weakness of conventional infrastructure, Okonkwo argues, is its habit of chasing one fix at a time; lasting results demand a move toward many-sided methods that fold in natural processes while drawing in and rewarding the communities and local decision-makers on the ground.
B. Roughly 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. Just 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. There 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. Weighing 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. A 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. So 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.
