At nearly 50,000 km², the Tsavo ecosystem is the largest continuous savannah range in Kenya. That has made it an excellent home to nearly a third of the country’s African savannah elephant population. On their range, amongst these constantly migrating behemoths of the savannah, lion, cape buffalo, zebra (both Grevy’s and common), giraffe, crocodile, hippopotamus and so many more species besides have been allowed to naturally proliferate.
Tsavo’s topographical diversity, its sheer size and the fact that it is the area of convergence for many of eastern Kenya’s most important waterways, elevates this land in importance. Despite that Tsavo needs no addition to its credentials as an exhibition of why protected lands are so important, there is one further reason that we believe warrants greater publicity.
Hirola: the world’s most endangered antelope
The IUCN classifies the hirola as Critically Endangered. Considering its status as the most endangered antelope in the world, it is of little surprise that the hirola is not well-known. Hirola are middle-sized antelope, around 1.2 metres tall and can be as heavy as 118 kg.
They go by a number of nicknames. The Hirola was once considered ‘The Hunter’s Antelope’. The name was given to it by a big game hunter in the late 19th century, and presumably reflects how even then the Hirola was a rare sighting. It is also, on account of the white chevron and eye-lining markings on its face, affectionately considered ‘The Four-eyed Antelope’.
Considered a good omen for cattle-keeping by pastoralist communities in Somalia, the hirola derives its species name from the Somali word ‘arawla’ which is a description of its tawny coat colour.
It is thought that the pre-historic range of the hirola once extended as far south as the cape. Today, however, the global population of hirola are limited to a small stretch of the Somali-Kenya border, and one other, translocated population.
That total population, today and with no hirola in captivity, stands at around 500 individuals.
Over the last four decades, the hirola has witnessed a 95% decline to its population size. Driven largely by rinderpest outbreaks in the 1980s, the former population of 15,000 individuals, is now critically endangered.
Conservation efforts are hindered by the fact of Somalia’s historic civil strife. Protection and fact-finding operations in Kenya’s northern neighbour’s territory are very difficult to organise. Some conservation organisations believe, in fact, that the hirola are extinct in Somalia.
As a result, the 497 individuals credited as living in Kenya during the country’s 2021 national wildlife census are of huge importance to the survival of the species.
The degrading range of the hirola, and how Tsavo stepped in
Hirola are selective in their feeding habits. They tend only to eat of short, new grass. Their natural range is something between thorn bushland and open bush grassland with less than 30% tree cover.
In north-eastern Kenya, where conservation efforts are proactive and ongoing, the rangelands of these creatures is changing. Tree cover has increased, blocking the emergence of new grass, and there is increased competition with pastoralists. Furthermore, the frequency and violence of recent droughts poses as much of a threat to hirola as it does to all of east Africa’s wildlife.
Hirola populations, still threatened by rinderpest, by predation, habitat loss and drought, have not recovered from their 1980s population loss. Today, they are, quite obviously, on the brink of extinction.
In 1963, before even the rinderpest outbreak, hirola were considered in need of protection. The Kenya Wildlife Services saw fit to translocate a small population, 30 strong, of hirola antelope from their normal range, in north-eastern Kenya, to the Tsavo East National Park.
It is thought that of those 30 translocated creatures, between 11 and 19 animals survived their initial rehoming. Those numbers suggest that the initial adjustment was difficult.
Today, however, the hirola population extant in the Tsavo ecosystem stands at a reported 74 individuals. From those 11 to 19 individuals, and augmented by a second translocated group of 10 individuals in 1996, a growing population has emerged.
Considering the IUCN status of the hirola, each of the Tsavo Conservation Area’s conservation groups keep an eye out for our naturalised population members. From the skies, we keep note of their distribution and locations. Thanks to the implementation of our IUCN’s Save Our Species project, co-funded by the European Union, we are optimistic regarding our mission to make the bespectacled antelope of northern Kenya feel at home here in Tsavo.
This publication was produced with the financial support of the European Union through IUCN Save Our Species. Its contents are the sole responsibility of Tsavo Trust and do not necessarily reflect the views of IUCN or the European Union.