from Sunday Herald, 10 August 2014
A proposed new traffic highway through the Serengeti in eastern Africa would be “catastrophic” for 1.5 million migrating wildebeests and zebras, a leading Glasgow scientist has warned.
The Tanzanian government is pushing ahead with plans for a new 50-kilometre road across the Serengeti National Park. But Dr Grant Hopcraft, from the University of Glasgow’s centre for population and ecosystem health, says that this will disrupt a mass migration regarded as one of the most spectacular sights of the natural world.
Every year about 1.3 million wildebeest, also known as gnus, and 250,000 zebras move hundreds of kilometres across vast grasslands and woodlands in search of food and water. En route, some are killed by lions on the plains or eaten by crocodiles as they cross the Mara River in the north.
But now they are facing a new threat from humans. The planned road, which could carry as many as 3,000 vehicles across the Serengeti every day, would cut straight across their path.
Hopcraft is in no doubt about the damage this would do. “A road would have catastrophic effects on how these animals migrate,” he said.
“It would separate their dry season refuge from their wet season calving grounds. All 1.3 million wildebeest and 250,000 zebra would have to cross that road in order to access the Mara River which is the only source of water during the dry season.”
The road is designed to create a trade route from Dar es Salaam and other Indian Ocean ports to Lake Victoria, Uganda, Kenya, Burundi and Rwanda. It has been a heated source of controversy between conservationists and the Tanzanian authorities for decades.
In June the East Africa Court of Justice ruled that constructing a tarmac road from Loliondo-Kleins Gate to Mugumu would be “unlawful” and “could cause irreversible damage to the property’s outstanding universal value.” But it left open the possibility of building a gravel road.
Last month, East African Business Week reported that local authorities in Arusha in Tanzania were pressing for the road to go ahead. “We shouldn’t be discouraged by anyone, we need to continue with our plans,” said Monduli district commissioner Jowika Kasunga.
Conservationists pointed out that the plans would take tarmac road right to the edge of the Serengeti National Park. This would hugely increase the pressure to extend into the park and made a road more likely in years to come, they argued.
“The big fear is that although the court judgement rules against a tarmac road, an improved gravel road – which could be almost as environmentally damaging – is not precluded,” said Dr Chris Magin, who co-ordinates work in Tanzania for the Royal Society for the Protection of Birds.
“If allowed to go ahead, this would be a road to ruin for one of the world’s greatest wildlife spectacles, disrupting the Serengeti’s famous mass migration and slicing up a pristine ecosystem.”
Along with colleagues from Germany, Argentina, Australia, Canada, The Netherlands and Tanzania, Hopcraft has just published a study into the influences on migration patterns of wildebeests and zebras. Over the past ten years 40 animals have been fitted with collars that use satellite and mobile phone technology to track their movements.
The results show that by far the biggest factor in the choice of migration routes is the need to avoid the threat of humans and human developments. “The impact of humans trumps everything else,” said Hopcraft.
“This provides critical insights as to why other migrations are collapsing,” he suggested. Numbers of saiga antelopes migrating across the Mongolian Steppes, pronghorn antelopes across the US state of Montana, and caribou and bison across North America have all been declining.
“There are only a handful of places left in the world where animals can still migrate, and in these locations many of the populations are declining at an alarming rate,” he added. “The Serengeti is one of the last strongholds and even this ecosystem is threatened by humans, despite its World Heritage status.”
Wildebeests and zebras are also under threat from poaching, with some evidence suggesting that
80,000 wildebeests are illegally hunted illegally every year for the bushmeat trade. “When these animals encounter areas of high poaching, both species attempt to exit the area as soon as possible by moving a long way and in straight lines, regardless of the food,” said Hopcraft.
“It appears as though they can detect risky areas and respond accordingly, which means if we want to protect migrations we need to focus on managing humans and not the animals.”
He added: “These intact ecosystems where natural process such as migrations have occurred for thousands of years serve as a critical benchmark against which we can measure our own impact.”
About 150,000 adult wildebeests are killed every year by predators, poaching, accidents and starvation. Their young are unusual in that they are born to run, with most starting to run within an hour of birth.
The Tanzanian government did not respond to requests to comment.
The Serengeti
The Serengeti in eastern Africa is home to some of the most spectacular wildlife on the planet. As well as the mass migrations of wildebeests and zebras, it has 75 large mammal species and 550 different types of birds.
These include nearly all the animals that people associate with the vast plains of Africa – lions, leopards, cheetas, elephants, rhinos, hippos and giraffes. There are also gazelles, buffalos, warthogs, hyenas, jackals, baboons, ostriches, storks, eagles, vultures, crocodiles and over 100 different types of dung beetle.
The whole area is a massive eco-system covering 25,000 square kilometres of northern Tanzania and southwestern Kenya. Comprising of grasslands, Acacia woodlands and scattered mountains, it includes the Serengeti National Park, two United Nations World Heritage sites and a series of other game reserves and conservation areas.
Traditionally home to nomadic Maasai cattle farmers, Serengeti means “the place where the land moves on for ever”. Its national park is visited by 90,000 tourists a year.
“The Serengeti ecosystem is one of the oldest on earth,” said Lota Melamari, the director general of Tanzania National Parks. “The essential features of climate, vegetation and fauna have barely changed in the past million years.”
He added: “Early man himself made an appearance in Olduvai Gorge about two million years ago. Some patterns of life, death, adaptation and migration are as old as the hills themselves.”
Grant Hopcraft, a Serengeti expert from the University of Glasgow, pointed out that the amount of rainfall and the fertility of the soil varied hugely across the area. This helped to explain why some animals felt impelled to travel long distances in search of food and water.
There is only one river that flows all year round through the Serengeti, and that is the Mara. It runs from the Mau highland forests of Kenya through the northern Serengeti and into Lake Victoria at Musoma.
The altitude of the Serengeti plains varies between 1,600 and 1,800 metres above sea level. The temperature across the whole area can range from 15 to 20 degrees centigrade.
Mass migrations across the world
animal / area / distance / numbers migrating
Blue wildebeest / Serengeti, Tanzania / 600km / 1.3m
Burchell’s zebra / Serengeti, Tanzania / 200km / 200,000
Gazelles / Serengeti, Tanzania / 200km / 350,000
Eland / Serengeti, Tanzania / 400km / 12,000
White-eared kob / Boma-Jonglei, Sudan / 400km / 1m
Hartebeest / Botswana / 400km / 40,000
Bison / Yellowstone, USA / 160km / 2,000
Elk / Wyoming, USA / 200km / 11,000
Caribou / Northwest Territories, Canada / 3,000km / 200,000
Siberian roe deer / Russia / 1,000km / 30,000
Mongolian gazelle / Dornogovi, Mongolia / 1,000km / 900,000
Saiga / Kazakhstan / 2,400km / 70,000
source: Endangered Species Research
Comments