-The Serengeti-Mara squeeze, one of the world’s most iconic ecosystems, is under pressure
-Increased human activity is 'squeezing the wildlife in its core', damaging habitation and disrupting migration routes
The over two million wildebeest migrating between Kenya and Tanzania are nursing a grudge against human beings.
In fact, they no longer throng Kenya’s Maasai Mara in large numbers in search of food and water.
The wildebeest join half a million gazelle and 200,000 zebra in the perilous trek from the Serengeti Park in Tanzania to the Maasai Mara reserve every year. All in all, they number about two million.
But now, the destination in Narok county is no longer attractive, following massive encroachment.
The 40,000 sq km Serengeti-Mara plain that straddles the border of Kenya and Tanzania is famous for its abundant and diverse wildlife.
It is also home to one of the wonders of the world: the Serengeti-Mara wildebeest migration.
The area is made up of pastoral community lands and 12 major protected areas, including the world-famous Maasai Mara national reserve and the Serengeti National Park.
The pastoral community lands make up what is now called the “core protected area”.
But despite its vast protected areas, the Serengeti-Mara is being threatened.
In a disturbing study, scientists have found that the once-attractive jewel is no more.
The research, published in the Science Journal March 29, shows how activities by people — like farming, erecting fences and settlements — are proliferating around the borders of the core protected areas.
This is putting huge pressure on the area’s environment, natural resources and wildlife.
This is the first time a large team of scientists from seven countries, pooled together various lines of evidence — like ground vegetation monitoring, aerial surveys of animals and GPS tracked animals — to show the impact of human activity on the Serengeti-Mara.
The study, led by the University of Groningen and with collaborators at 11 institutions around the world, has data covering 40 years.
The research indicated the activities of people have caused extreme changes to the habitat.
It has significantly reduced the amount of grass and, because of farms, settlements and fences, the landscape has become fragmented. This means animals can’t move freely to find resources or mate.
Key ecological functions have also changed.
There are less manmade or wildfires, which means trees and shrubs are able to take root, soils are damaged, and so the land produces fewer plants, and the area becomes more sensitive to climate change.
Dr Michiel Veldhuis from the University of Groningen was the lead author of the study.
Veldhuis said there is an urgent need to rethink how boundaries of protected areas are managed to be able to conserve biodiversity.
Dr Joseph Ogutu from the University of Hohenheim said the intense compression of a large protected area, such as the Serengeti-Mara, should ring alarm bells because most other protected areas are far smaller in size.
Expanding human population size, livestock and human activities pose serious and unprecedented threats to wildlife populationsResearcher Dr Joseph Ogutu, University of Hohenheim
"In countries where far more wildlife is still found outside than inside protected areas, such as Kenya, where more than 65 per cent of wildlife occur outside protected areas, expanding human population size, livestock and human activities pose serious and unprecedented threats to wildlife populations," Ogutu said.
Tanzanian's director for Wildlife Research Institute, Dr Simon Mduma, said the results come at the right time, as the Tanzanian government is now taking important steps to address protected areas' boundary issues on a national level.
"This paper provides important scientific evidence of the far-ranging consequences of the increased human pressures around the Serengeti-Mara ecosystem, information that is now urgently needed by policymakers and politicians," Mduma said.
Some 62 aerial surveys were used, from 1977 to 2016, to examine changes to wildlife, livestock and settlements around the area.
To determine the growth of human population, data was collected by researchers from the Kenyan and Tanzanian governments.
The researchers found out that there were 26 per cent more people within a 60km radius of the core protected area boundary.
There was an increase from 4.6 million to 5.8 million people in 13 years, with the population growth rate even higher within a 15km radius.
MORE FENCING AND HABITATION
As the human population increased, there was more livestock, settlements and fences.
Researchers found out that the number of fenced plots has increased by more than 20 per cent since 2010 outside of the core protected area, in the Mara Region of Kenya.
This has resulted in blockage of wildlife dispersal areas and corridors.
The researchers also found that there was a high density of bomas (settlements), and the number was rising in parts of the Mara by up to three new bomas per square kilometre per year.
They also found out that the number of sheep and goats had substantially increased — by 276.2 per cent.
The number of cattle within the Narok region had slightly decreased by 9.4 per cent.
However, the livestock did not just stay on the boundaries of the protected areas. They were going into the protected areas, dealing a major blow to the wildlife.
Researchers found out that the livestock paths were prevalent and visible up to 5km, often even further, inside.
From 1977 to 2016, the number of resident wildlife species declined by between 40 per cent and 87 per cent. In addition, 63.5 per cent fewer migratory wildebeest used the reserve.
MORE LIVESTOCK, LESS WILDLIFE
This flags that illegal grazing is happening, which reduces the quantity and quality of food available for wildlife.
For instance, the researchers found out that, from 1977 to 2016, illegal incursions into the Maasai Mara national reserve by cattle increased by 1,053 per cent and by sheep and goats by 1,174 per cent.
They also found out that the number of resident wildlife species had declined by between 40 per cent and 87 per cent. In addition, 63.5 per cent fewer migratory wildebeest used the reserve.
Agricultural activities around the area also bothered the researchers. Over 34 years, the amount of agriculture happening around the border went up by 17 per cent.
It now covers 54 per cent of the land around the protected area and has destroyed large natural habitats close by.
Coupled with high livestock densities, this has intensified the pressure to graze livestock inside protected areas.
The biggest impact has been on migratory animals – like wildebeest.
Using data gathered from GPS radio-collared wildebeest, researchers found out that they were coming together in dense groups at specific locations inside core protected areas, as opposed to ranging widely inside and outside.
This reduces the amount of grass each animal has to eat and, because of over-grazing, weakens the capacity of soil to store nutrients and carbon.
This means the land is less productive and it increases the area’s sensitivity to weather changes.
Also, there was less natural or wildfires, which are key to maintaining grasslands.
When livestock grazing removes grass, young trees and shrubs take root. This turns grasslands into shrublands or woodlands.
Wild grazers, like hartebeest, are then likely to be replaced by animals that eat leaves and twigs, like giraffes.
Researchers said the most troubling changes have taken place in Narok county, located in southwestern Kenya.
This area of about 17,933 square kilometres includes the protected Masai Mara Reserve, wildlife conservancies and community land. Wildlife numbers in this area have dramatically declined.
This is a big worry because the Maasai Mara is where migratory wildlife goes to eat and drink water in the dry season.
In its protected areas, over about 40 years, the number of cattle (40 per cent), sheep and goats (189.6 per cent) all increased, and virtually all the large wildlife species such as giraffe and eland.
The number of migratory wildebeest declined by about 80 per cent and zebra by 75 per cent.
The researchers said the intense and extensive changes mean that the Serengeti-Mara area’s wildlife has an unsure future.
The findings, researchers said, called for an immediate and robust response to save the future of the region’s wildlife populations, their habitats and the tourism revenue they bring from imminent jeopardy.
They called for better protection of migration and dispersal corridors along the edges of the Serengeti-Mara.
Livestock numbers, fences, charcoal trade, cultivation and settlements should be regulated.
And illegal livestock grazing and poaching must be controlled in protected areas. Also, conservation benefits should be fairly distributed to communities living around the Serengeti-Mara.