'Very big boys' Elephants and humans learn to co-exist as habitat changes

At nearly 3.5 metres (11.5ft) tall and weighing as much as a bus, you could be forgiven for assuming that Goshi - one of an estimated 30 "super-tusker" elephants left in Africa - would be easy to find.

- Patrick Greenfield

The radio tracker picking up his signal beeps encouragingly, indicating the giant bull is within 200 metres. But the dry season has turned the mass of arid acacia scrubland grey, and everything seems to resemble an elephant.

Even when they are invisible, the huge herbivores shape the landscape here. There are 17,000 elephants across the Tsavo region, Kenya's largest protected area, which is divided in two. Each year, elephants wander huge distances between feeding grounds, following the seasonal rains as they have done for thousands of years.

But the thicket where Goshi and his accompanying group of male elephants are hiding is a frontier of rapidly changing habitat. Two lines of pylons pass through the land next to the Mombasa-Nairobi highway, where lorries roar past night and day. About 100 metres away, the Chinese-built SGR railway bisects the Tsavo area.

Some of the elephants will brave the railway's underpasses - but others are scared off by the traffic and noise. During seasonal migrations, hundreds gather at bottlenecks and blocked routes. Conservationists fear a proposed four-lane extension to the highway could cut off their migration routes for ever. Electric fences, new roads, railway lines and growing human settlements are crosshatching the elephant passages, fragmenting access to food and water, and putting them in competition with people for resources.

While there are no definitive figures for the scale of the problem, researchers say it is a pattern happening across elephant rangelands in Africa. Northern Kenya is one of the few places with data, which shows that human-elephant conflict has overtaken poaching as the main threat to the mammals in recent years.

For people and elephants, those clashes are proving deadly.