You’re likely to spot a zebra on safari in Kenya, but chances are it’ll be the more common plains zebra (formerly Burchell’s zebra). Its much rarer cousin, the Grevy’s zebra, is mainly found in the arid and semi-arid landscapes of northern Kenya. It’s not too difficult to tell the two species apart: the Grevy’s is larger than the plains zebra, with narrower stripes, distinctive round ears, a black dorsal stripe and a white belly.
The key difference between the two is the fact that the Grevy’s zebra is one of the most endangered mammals on the planet. Their global wild population has plummeted from approximately 15,000 in the 1970s, to under 2,500 today. The vast majority of this global population (over 90%) can be found in Kenya, while the rest are limited to ranges in southern and north-eastern Ethiopia.
Habitat fragmentation, competition with livestock for overgrazed land, predation pressure and climate change, have all contributed to this drastic decline. The Grevy’s zebra is now listed as Endangered A1a, 2c by the IUCN/SSC Equid Specialist Group, and is also listed on Appendix I of the Convention on International Trade of Endangered Species of Flora and Fauna (CITES), which offers them the highest protection against illegal trading.
To help protect the Grevy’s in northern Kenya, and to get a better understanding of the issues they face, a range of conservation organisations constantly monitor their population and demographics. These include the Grevy’s Zebra Trust, the Mpala Research Centre, the Lewa Wildlife Conservancy, Marwell Wildlife and Northern Rangeland Trust’s community conservancies.
In 2016, these organisations came together and conceived the Great Grevy’s Rally (GGR) – a unique way to get a more accurate picture of Kenya’s Grevy’s zebra population. The rally brought together scientists, landowners, conservancies and members of the public, who drove round designated areas across northern Kenya, taking photos of each individual Grevy’s zebra that they came across. More than 500 people took over 40,000 photographs, which were analysed using sophisticated stripe recognition software. Through the census, the GGR partners found the Grevy’s zebra population to be 2,350 in northern Kenya.
Thanks to the success of the first rally, a second one is being held in a couple of weeks, on the 27th and 28th January 2018. The concept hasn’t changed, although this second census will also include the reticulated giraffe, which has also suffered a drastic population decline. Over the last 30 years, it is estimated that their numbers in Kenya have decreased by 80%.
To learn more about the second Great Grevy’s Rally, I had a chat with the Event Organiser, Kasmira Cockerill. Kasmira explained how easy it is for members of the public to get involved in the rally as citizen scientists.
All you have to do is visit www.greatgrevysrally.com, select the accommodation page, and choose from a variety of options across northern Kenya. These range from isolated self-catering campsites in community conservancies, to some of Kenya’s best lodges and tented camps – like Saruni Samburu and Laikipia Wilderness Camp, who are offering special rates for the rally.
Each team that registers (at just Ksh 2,000 per vehicle) will then travel to Nanyuki Sports Club on Friday 26th January to meet the GGR organisers, pick up the necessary materials – like a GPS camera – and receive a brief training on data collection. From here the teams then drive to their destination of choice, and spend two full days exploring their designated areas and taking photos of each Grevy’s zebra and reticulated giraffe that they come across.
The organisers have taken care to ensure that the teams are safe in their respective areas. Each team will be accompanied by a ranger to help with the data collection, navigation and communication with conservancy management.
On Monday 29th January, the teams will then travel back to Nanyuki to hand over their data and equipment to the GGR organisers, who will transfer the photos to the scientists for analysis.
The photos will be processed by Image Based Ecological Information System (IBEIS) software, which is able to identify a Grevy’s zebra individual, as well as its age and sex, from its unique stripe pattern. So in addition to providing insights on the numbers and distribution of Grevy’s in the areas covered by the census, the rally will also reveal their age and sex structures, allowing the GGR partners to assess whether the overall population is stable, growing or decreasing.
The census will help to inform policy decisions and conservation strategies aimed at ensuring the sustainable development of the targeted areas – benefitting a wide range of grazing species, as well as the region’s communities.
But it will also provide a unique opportunity for members of the public to become citizen scientists for a weekend – contributing to the protection of an extremely rare animal, and experiencing stunning parts of the country seldom explored.