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Life

East Africa’s drought threatens iconic wildebeest migration

By Adam Popescu

24 May 2017

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By no means their only threat

Courtesy of Gina Bender

The wildebeest look tired. Skittish at the slightest sound, their hooves perpetually pound the dusty plain until they kick up a cloud that obscures the hundreds of animals forming the herd.

Under the dust, the short grass is yellow and grey, if it’s there at all. How do these animals find sustenance amid this sparseness, I wonder? Where is the water?

“Drought,” answers Ngiimba, my Maasai guide. “More than a year now. Killed over 50 per cent of livestock.”

I’m in Tanzania’s Serengeti National Park, a sprawling wilderness the size of Belgium. And though there is wildlife seemingly everywhere – lions, cheetahs, elephants, zebras, wildebeest – Ngiimba’s words hint at trouble.

More than 90,000 tourists flock here every year to see the Serengeti’s great annual migration, in which as many as 2 million wildebeest, zebras and gazelles travel thousands of kilometres between Tanzania and Kenya. The grazers cross rivers and arid scrub along the way, and leave a trail of droppings in their wake that keeps soils rich in nutrients, giving life to the land.

But there’s a story that travel sites and Instagram posts don’t share. Although biodiversity here ranks among the world’s highest, Africa is particularly vulnerable to the effects of climate change – and rising temperatures can cut crop yields by as much as 20 per cent. Factor in an already depleted ecosystem and an infrastructure unable to handle a fast-growing population, and East Africa faces a bleak future.

Not a drop

It’s supposed to be the rainy season, but not a drop has fallen in my 10 days here. The parched earth reminds me of my native California, but whereas we have dams and irrigation to deal with water shortages, there are no such facilities here.

The relationship to water stretches far beyond the savannah, and affects humans as much as wild animals. The water shortages are causing humans to compete with wildlife for resources and push into their territory.

It is not uncommon for locals to lead their flocks onto protected lands to graze. Increasingly, people find that their crops and livestock are dying, leading to a food shortage that could become a humanitarian crisis.

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“The biggest problem is that people and wildlife don’t recover,” warns Friederike Otto at the University of Oxford, who has studied East Africa’s drought since 2014. “The soil cannot recover, so deep soil moisture cannot rebuild.”

That means a bad cycle is poised to get worse. The only major river in the area – the Mara – could dry up, further stunting grassland growth, imperilling resources for ungulates, and increasing predation.

Water hazards

When rainfall does hit the parched earth, the potential for flash floods increases, and these can make it near-impossible for herds to cross rivers.

Sparse rain also means wildlife must scatter over a wider area in search of water, which increases animals’ odds of straying into developed areas, where fencing can block their way  – a big issue in Kenya. And predators are emboldened by the confusion caused by the lack of water (I saw three kills in one afternoon following wildebeest).

If the bodies of water in the area disappear entirely, 30 per cent of the wildebeest migrating through could die within two weeks.

There has even been talk of a paved highway in the Serengeti, says David Blanton, co-founder of non-profit organisation Serengeti Watch. The government shelved plans, partly because of a public outcry and a court ruling, but Blanton says Tanzania continues to look at development projects.

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Maasai country

Courtesy of Gina Bender

North of the border, in Kenya, there’s talk of damming the Mara, which Blanton says would “decimate the migration”. To that end, his organisation helps train locals with conservation and journalism training programmes, encouraging them to become invested in protecting their environment. “This place has to be saved by the people who own it and live next to it,” he says.

It’s sobering stuff. East Africa’s population has increased by 74 per cent between 1988 and 2008,  and could further double by 2050. Poaching and the bushmeat trade will skyrocket and this land may soon be unrecognisable.

“We have to bridge the gap between scientists and politicians,” says Eivin Røskaft, a conservation biologist who heads the European Union-funded AfricanBioServices project. “One of the biggest arguments is potential tourism. As long as tourists come to give money, we can use that argument for politicians. Otherwise, it’s really hard to find good arguments why they should save nature.”

A third of Tanzania’s land is protected, but Røskaft says factors such as the population growth and rising demand for natural resources threaten not only wildebeest migration, but all wildlife in the area. “If there’s no will from the West, these trends will continue,” he says.

Read more: Africa’s road-building frenzy will transform continent

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