In the lush greens of Karen-Hardy just next to Nairobi national park, a young male Rothschild’s giraffe called Jock is feeding on greenish-coloured pellets from a container placed on a raised platform.

As excited tourists and schoolchildren take photos of Jock, George Njagi, an education officer at the African Fund for Endangered Wildlife’s (AFEW) Giraffe Centre, guides me up the platform steps. From the top I spot more giraffes browsing on acacia trees in this island of serenity just south of the noisy and chaotic Kenyan capital.

Jock is one of eight Rothschild’s resident on this 120-acre breeding sanctuary. “We provide the endangered Rothschild’s with a conducive breeding environment before relocating mature offspring to the wild in a bid to boost their numbers,” Njagi tells me.

There are thought to be only around 1500 Rothschild’s left in the wild – making them one the world’s most endangered populations. They are scattered across the acacia woodlands of Kenya’s central rift valley and in Uganda’s Murchison falls, where another conservation group, the Giraffe Conservation Foundation, is studying the animals.

Earlier this week that Murchison Falls national park could be damaged by planned oil drilling, putting the giraffe at risk. British, French and Chinese oil exploration has already damaged the park, the charity said.

Giraffe conservation

French oil company Total said in a statement that it is working in collaboration with the Giraffe Conservation Foundation on a one-year project to understand the ecology and distribution of the giraffes in the national park. “This is the first time such an intensive study is being undertaken on these giraffes,” it said.

Little is known about these giraffes. Until recently, it was thought to be one of nine subspecies of a single giraffe species. But a genetic analysis found that there are actually four species, and suggests that Rothschild’s giraffe falls within the Northern giraffe species (Giraffa camelopardalis). It remains one of the most endangered types of giraffe.

When Zoe Muller embarked on her research on giraffes in East Africa’s savannah bushlands one of her objectives was to gain deeper understanding of social behaviour of the iconic animals that once numbered in their hundreds of thousands.

One day, as she tracked the animals deep inside Kenya’s Soysambu conservancy, she stumbled upon a dead Rothschild’s giraffe calf surrounded by a group of obviously distressed adult females, circling around and apparently inspecting the body.

Over the coming five days she witnessed never-before documented giraffe behaviour.

“The mother stayed with the dead calf’s body for five days, and in that time I never saw her eat or drink. So she was watching over her calf, even though it had died – and at great cost to herself,” says Muller, part of the Rothschild’s giraffe project at the Giraffe Research & Conservation Trust.

Structured society

Months of study led Muller to conclude that giraffes live in structured, complex and organised family units very much like elephants.

This knowledge will be critical in devising strategies to save the tallest mammal species, she says. Ěý“To effectively conserve a species in the wild we need to know about its behaviour and social organisation,” says Muller. For example, “studies have shown in other species – e.g. in elephants – that moving family units is more successful for translocations than moving random individuals.”

Overall, giraffe numbers have tumbled over the past 15 years and various studies in 2014 indicate that they had plummeted by up to 40 per cent. The biggest threats to the species are loss of habitat, poaching and a growing human population.

The Rothschild’s giraffe took the severest beating. This is because they prefer living in habitats that are also suitable for agriculture, says Sam Weru, a wildlife and conservation consultant with Dalvis Consulting.

“In Kenya, for example, 70 per cent of wildlife lives outside protected areas, so when ranches are subdivided the Rothschild’s lose their habitat, unlike their relatives such as the Maasai giraffe, which has a relatively wider range,” says Weru.

He fears giraffes are not seen as a “sexy” species and thus the lack of widespread awareness or campaigns to save them.

Loss of biodiversity in Lake Tanganyika, Africa’s oldest and deepest lake, has been driven by 500 years of sustained climate warming, a study of core sediments has found.

This has led to a decline in the abundance of the lake’s fish that pre-dates commercial fisheries.

We have known that the warming climate is transforming lakes worldwide, but a lack of consistent climate and fishery data from the tropics has meant that little was known about how lakes in the region were affected.

So at the University of Arizona in Tucson and colleagues analysed sediment cores from Lake Tanganyika in East Africa to study proxies of temperature, algal production and abundance of fish fossils over the past 1500 years.

Lake Tanganyika’s surface waters are fertilised by an upwelling of nutrient-rich water during the windy season. The team found that rising temperatures have been preventing water layers from mixing.

This has reduced oxygenation in the lower water layers and cut populations of the algae, molluscs and crustaceans that the fish depend on by as much as 38 per cent.

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Lake layers

This stratification kills productivity and narrows the oxygen-rich coastal habitat where most endemic species are found.

“As the climate warms it makes the surface of the lake warm,” says Cohen. “And Tanganyika being a deep tropical lake doesn’t mix every year as lakes in cooler climates do, instead the surface warmer waters mostly just sit on top of the cooler water below.”

Climate warming and intensifying stratification have almost certainly reduced potential fishery production, says the team.

They found a correlation between rising temperatures and declining biodiversity, which suggests that declines in the abundance of fish pre-date the establishment of commercial fisheries in the mid-20^th century.

This means that while overfishing contributes to loss of biodiversity in Lake Tanganyika, which is renowned for the number of species that live in it, the temperature rise seems to be the main driver.

The ecological consequences of climate change for other lakes in Africa willĚýdepend on their shape and depth.

Other Great Lakes in theĚýregion, such as Lake Kivu and Lake Malawi, are likely to see a similar loss of diversity, says Cohen.

On the other hand, Lake Victoria has a shallow basin and hardly experiences stratification, so should be spared the same fate as Lake Tanganyika, says at the Kenya Marine and Fisheries Research Institute.

But it is hard to predict if and how lake life will survive in a warmer future, he says. Much will depend on genetics and how well different species adapt.

Osore calls for local people to be involved in mitigation measures, as those living alongside the lake may have a better understanding of the changes.

Journal reference: PNAS, DOI:

Read more: Many of world’s lakes are vanishing and some may be gone forever; Global browning: Why the world’s fresh water is getting murkier

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