For centuries, farmers in the fragile ecosystems
of the high Andes have looked to the behaviour of plants and animals to figure
out what crops
to grow and when.
If reeds dried up in the late summer, rainless weather lay ahead, they
believed. If the Andean fox made a howling appearance, abundant rains were
thought sure to come.
But increasingly erratic weather that scientists attribute to global
warming is rendering their age-old methods less reliable, endangering
harvests in a region where life is hard in the best of times.
Experts may scoff at such folk science, but the men and women who till the
high mountain soil continue to swear by the traditional indicators, and
Bolivia's government has even incorporated them into climate reports provided
to farmers when it lacked modern data from meteorological stations.
"They work for me," assures Francisco Condori, 45, after checking
the previous night's precipitation on a homemade rain gauge on Lake Titicaca's
southern shore, the hills around him shining purple with flowering potato
Condori is a well-heeded font of ancestral knowledge for fellow farmers in
these treeless climes frequently punished by frosts, hailstorms and drought.
In the reeds on Titicaca's shore, he points out the height of the nests
built by birds known as quilli quilli, a diminutive species similar to
hummingbirds. Farmers have long used the locations of those nests as measures
of how much the lake will rise and the amount of rainfall to come.
"This year they initially built their nests about 40 centimeters (1.3
feet) above the water level. Then they dismantled them," Condori says.
Twice, in fact, did the birds dismantle nests before finally reweaving them at
nearly twice their original height.
"We knew it was going to rain a lot," he says.
And so it did, so much so that rivers in the Amazon basin have flooded their
banks, submerging thousands of homes. That rain augured well, by contrast, for
this Aymara community's potato crop.
Landlocked and poor, Bolivia relies on a weak meteorological reporting
system – with just 50 weather stations nationwide. Farming is also decidedly
low tech in the mountainous part of the country. Ox-driven plows overwhelmingly
outnumber tractors, a far cry from the eastern lowlands, where highly mechanised
rice and soy farming yields the bulk of Bolivian agricultural exports.
Condori says the "bio-indicators" he follows most closely have
helped reduce agricultural losses by 40% in Cutusuma and surrounding communities.
Scientists, however, stress there are no empirical data to support the beliefs.
The indicators are catalogued in what are known as Pachagrama, registries
whose name derives from "Pachamama", the native Andean word for
"Mother Earth". Communities compile and share the registry
information, which is especially crucial from September to November when the
dry season ends and farmers need to know how soon to plant, when the rains will
begin and how long they will last.
It's in that season they look for guidance to the southern lapwing, a
long-legged plover that likes grasslands. If the female drops her eggs on the
crest of a furrow, a lot of rain is expected and farmers will plant potatoes
rather than quinoa, which requires less water. But if she deposits them inside
the furrow, it supposedly will be a dry year.
The size of the spots on the eggs is another indicator of whether to plant
potatoes or quinoa.
"If the spots are big, it's potatoes. If they are small, it's
quinoa," Condori says. Lately, however, the birds have been erratic in
where they lay their eggs.
No scientific studies yet
Other indicators Condori follows such as wind direction and cloud movement
traditionally have told farmers whether frosts are imminent. A strong easterly
breeze on March 13 indicates as much, he says.
Reading those signs has become more difficult as climate
change alters everything from animal behaviour to the weather. There are no
scientific studies as yet on how climate change may modify animal behaviour
used as indicators.
"Yet it is also certain that these meteorological phenomena are
occurring in an atmosphere that has warmed by 0.8 degrees (Celsius)," since
pre-industrial times, said Dirk Hoffmann, a German who heads the nonprofit
Bolivian Mountain Institute.
Indeed, the observations of local indigenous coincide with scientific data
that show the rainy season is both less predictable and begins later, Hoffman
said. "Previously, the rainy period lasted four months. Now it's shorter
but the amount of rain has not decreased," he said.
In Bolivia's drier southern high plains, farmers who follow one popular
traditional indicator say they were misled this year when the Andean fox did
not appear and howl full-throated from the hilltops in August or September.
That's a typical indicator of abundant rain, said Jose Luis Quiruchi, a Quechua
community leader in the Potosi region, Bolivia's poorest.
Reeds also dried up at that time of year, another traditional indicator of
drier weather ahead.
Strategy against climate change
"We expected little rain, but instead the opposite happened,"
Quiruchi said. Anticipating drier conditions, farmers planted potatoes in
low-lying areas. Now, they fear the tubers will become water-logged and rot.
Agronomist Nelson Tapia of the Universidad Mayor de San Simon in Cochabamba
says climate change offers some benefits for high-altitude farmers.
They can grow certain fruits and vegetables at higher altitudes, with
apricots and corn as well as citrus fruits now growing as high up as 3,000
meters (9,800 feet) in the Cochabamba valley.
However, the negative effects are greater, he said, with highland farmers
losing crop variety and planting in shorter cycles.
The director of the government's risk management agency, Lucio Tito, insists
the traditional indicators still have their value despite the changing climate.
"They should not be dismissed," he said. "They should be
combined with scientific knowledge to form a strategy against climate change.
That's what we're doing."
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