Friday, 7 June 2013

MIGRATION ROUTES IN AFRICA... WHAT HAVE WE DONE?

Since the dawn of time animals have migrated. Be it to escape an unforgiving landscape, to search for new food and water resources, or for the purpose of breeding, it has been an essential part of their survival. But, as we do so often, humans have interfered and many of the natural migration routes have been cut off with fences, roads and building construction. One of the latest disasters humans have bestowed on our natural world is the plans to build a major highway through the Serengeti National Park and straight through one of the last migratory strongholds left in Africa, so called 'The Great Migration'.

'The Great Migration' is made up of millions of Blue Wildebeest, Zebra and Thompson's Gazelles who travel across the Serengeti over the border into the Masai Mara every year. Their journey begins on the Serengeti plains where from around December to June the Wildebeest breed and graze. They set off in late May or early June and over the course of several months make their way across the Masai Mara boarder where they graze on highly nutrient rich grasses. Then after spending time feeding and fattening up they turn around and go back. 

You can see the progression of their journey here: www.rhinoafrica.com/east-africa/great-migration.

It is not clear why the wildebeest make this journey and when it began, however it is perilous and over 250,000 wildebeest are killed, the majority of which from drowning whilst crossing the river.   

Little is known about the origins of migratory animals but it is clear that it is a phenomenon that has taken place for millions of years. Before human habitation in Africa, 2.6 million years ago, animals would have been free to roam with no borders. Around 100,000 years ago humans began to adapt and became hunters; one of the few predators which could follow migratory animals and rely on them as a food source. However this would have had little impact on the animals who would continue to move as they needed to. Then, 2,000 years ago, traders began to bring cattle into East Africa and many hunters became pastoralists. Initially this would have
impacted the migratory animals very little, even though the pastoralists likely followed the same routes. However it wasn’t long before cattle diseases began to spread to wild animals and the numbers of these animals dropped dramatically. It wasn’t until around 150 years ago that humans began to truly impact on their migratory neighbours as people began to fence off protected game reserves and private property. Alongside this farming was discovered to be a more profitable way of life and many pastoralists turned to farming, leaving much of the previous migratory land into agricultural farms. Shockingly between 1975 and 1995 the amount of agricultural land across Africa increased by an average of ten times.   

Across the globe humans have made an enormous impact on natural habitats, and in Africa this has had a devastating effect. Africa currently has the highest population growth with figures doubling every 24 years. This means a huge increase in forests clearing for firewood, living space, crops and domestic livestock. In the Masai Mara between 1970– 1995 agricultural land use increased from 4875ha to around 50,000ha. This had a direct impact on local wildebeest populations which dropped by a shocking 81%. In a similar circumstance it is believed that, under the unregulated agricultural land expansion adjacent to Tarangire National Park between 1988-2001, wildebeest populations dropped by 88%, hartebeest by 90% and gemsbok by 95%. Just to give a better picture in South Africa 12% of the land space is devoted to agricultural uses compared to the 3% which makes up natural reserves. 


Fencing of game reserves has had the greatest impact on migratory animals. The picture above shows a map of reserves in South Africa, the green sections are those which are fenced off. There are many good reasons for reserves to put fences up, and too often it has been only because of these fences that some species have been saved from complete extinction. However there are many areas where fences between reserves could safely be removed but the human obsession with money has meant that this is unlikely to happen any time soon.
The impact of these fences in some cases has been appalling. For instance between Botswana and Namibia in the 1960s after a series of droughts the numbers of wildebeest in fenced areas decline from 380,000 individuals to around 20,00. During the same period zebra disappeared from the Northern Kalahari as fencing blocked their access to water. This was repeated in the 1980s in the Southern Kalahari when more than 80,000 wildebeest and 10,000 hartebeest perished because fences cut off their access to water during severe droughts. Springbok, which are naturally migratory animals, no longer migrate at all because of fencing. 

In the Serengeti/Masai Mara the great migration route changes from year to year. Although the fence lines are currently suited to how the wildebeest and zebra move it is unclear whether this will still be suitable in ten, twenty or fifty years from now. In areas where reserves are surrounded by farms and settlements there may be nothing that conservationists can do to fix this situation; the land is already damaged and will take many years to recover (if it were ever handed back to nature). This could mean that in years to come animals will no longer migrate, and in some areas this could cause extinction of the local species.   

What is being done to help?

One way of allowing animals to exist as naturally as possible without preventing human progression is to create Wildlife Corridors which connect wildlife populations that have been separated by human activities such as roads, towns and buildings. This picture shows the first elephant corridor to be made in East Africa in 2011 which has reinstated an old migration route and allowed separated populations of elephants to re-join with one another. By creating wildlife corridors across Africa reserves that were once separated from one another because of major roads may be able to re-join and allow animals to move over a larger area.

Transfrontier National Parks are a relatively new idea which understands that animals do not understand country borders and is set to remove human barriers between National Parks so that animals can roam further. The Great Limpopo Transfrontier Park, for example, is set to be 35,000km2 (to put in perspective Wales is 20,780km2). The plan is to remove fences between Limpopo National Park, Kruger National Park, Gonarezhou National Park, Manjini Pan Sanctuary and Malipati Safari; it will link across Mozambique, South Africa and Zimbabwe. There are currently new plans to increase the park to 99,800km2. I think where this is feasible reserves should be linked allowing animals to migrate as they need to.   

But is all this progression really worth while when government's just turn around and make decisions such as building major highways through such fundamentally important areas such as the Serengeti? I understand that progression must happen, and we as Westerners have no right to demand others don't damage their wildlife, since we have so much damaged our own. But there are other options, the ability to build around the park...  yet again the human race won't take the harder route, all at the cost of our wild world. And in 100 years time, when all we have is concrete and glass, people will turn around and say "What have we done?".

This post was based on a presentation I did during my Field Guide Course. 

I know this is a long post, and if you have read it thank you so much! I hope you have found it interesting and will continue to check out my blogs. I promise not all will be so long! 


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