21 May 2022 | New Scientist | 49sheepdogs – the most commonly used
guardian dogs in the country – were present.
These wild herbivores compete with livestock
for pasture, so their absence provides an added
benefit to farmers.
Guardian dogs can even deliver unexpected
conservation benefits by protecting vulnerable
or threatened wildlife from predators. Their
presence has been found to increase the
number of nests of ground-nesting birds in
pastures where foxes, raccoons and skunks
would normally raid them. Indeed, Australian
researchers are now using dogs to enhance
biodiversity and create refuges for species
threatened by predation from foxes and cats.
On Middle Island, a small island connected
by a tidal sand bridge to Warrnambool in
south-western Australia, a team of Maremma
sheepdogs has been trained to guard a colony
of little penguins from fox attacks. Meanwhile,
researchers from Zoo Victoria and the
University of Tasmania are conducting trials
to see if Maremmas can protect a reintroduced
population of endangered marsupials called
eastern barred bandicoots. “If you reinstate a
top-level predator like a livestock guardian dog
on the landscape, they can have a role to play
in protecting our native wildlife,” says van
Bommel, who is involved in the trials.
For livestock guardian dogs to be truly
beneficial for wildlife conservation, humans
must play their part. For example, there is
evidence that guardian dogs that aren’t well
treated or properly fed are more likely to chase
or kill wildlife. “You can’t just throw those dogs
out there and expect them to do their thing,”
says Young. Van Bommel agrees. “Guarding
livestock is an instinct, but you still have to
nurture that instinct and guide it in the
right direction,” she says.
If we can get this right, van Bommel sees a
bright future for guardian dogs in promoting
harmonious coexistence between humans
and wildlife. She points out that consumers
are becoming ever more conscious of the
environmental impacts of the food they eat.
“This will put more pressure on farmers to
manage their land and grow livestock in a
more sustainable way,” she says. “If that trend
continues, livestock guardian dogs will have
a very big role to play.” ❚food. And by creating a “landscape of fear”,
their mere presence can influence the
behaviour, distribution and interactions of
prey animals. These wider ecological effects
are complex and scientists are just beginning
to understand them. “We are using dogs as
biological control agents without thinking
about the potential consequences on the
environment,” says Smith.
The evidence so far, however, indicates that
these consequences aren’t always negative. In
the sheep-grazing lands of Chilean Patagonia,
for instance, guardian dogs not only reduce
livestock predation by foxes, but also scare
away invasive European hares, which compete
with sheep for forage. The mere scent of the
dogs is sufficient to trigger fear in the hares.
“Hares are avoiding places where the dog
smell is present,” says Carolina Ugarte at the
University of Chile in Santiago. Likewise, in
Australia, van Bommel and Johnson found
that herbivores such as wallabies, deer and
kangaroos avoided areas where MaremmaISA
BE
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Isabelle Groc is a writer
and photographer based in
Vancouver, Canada, and author
of Conservation Canines: How
dogs work for the environmentsupposedly protecting livestock, leading
the researchers to conclude that there are
“unintended ecological effects” of using
guardian dogs.
The extent of this problem isn’t known,
but the consequences are clear in Namibia.
Cheetahs aren’t the only species that cause
sheep and goat losses there: leopards, caracals
and black-backed jackals also attack livestock.
In 2015, researchers reported that although
farmers ceased killing cheetahs and leopards
after they obtained a guardian dog, the
number of jackals killed by dogs and
people combined actually increased. “It’s
a philosophical question of whether you
prioritise cheetah conservation over the killing
of these other carnivores which have their
own ecological knock-on effects,” says Smith.
Guardian dogs have other ecological
impacts too. They have been implicated
in the spread of diseases to wild animals,
including endangered Ethiopian wolves. They
may also compete with other carnivores forThe Cheetah
Conservation Society
has placed 700 Kangal
dogs with herders
across Namibia