Great Grevy's Rally

Join us for the next Great Grevy’s Rally in 2020!



The first ever national census of Grevy’s zebra through citizen science, called the ‘Great Grevy’s Rally’ (GGR) took place on 30 and 31 January 2016. It brought together over 350 people including conservancy managers, conservation organisations, government officials, research scientists and members of the public from many parts of Kenya, who together sampled over 25,000 km2 across five counties! The teams drove through designated sampling blocks while photographing the right side of each individual Grevy's zebra observed with a GPS enabled digital camera. Over 40,000 images were taken!

Grevy Zebra

These photos were then processed by the IBEIS team (Image Based Ecological Information System) in the USA, and individual zebra were identified and mapped using their GPS locations. In this way the size of Grevy’s zebra populations, as well as their age structure, was estimated by region.

Results from the GGR 2016 showed that Kenya’s total Grevy’s zebra population consists of 2,350 +/- 93 individuals, with the age structure indicating that the population is stable and sustaining, with a combined foal/juvenile proportion of 30%.


The second GGR took place in January 2018 with more than double the number of participants. The results showed that despite the devastating 2017 drought, Kenya’s population of Grevy’s zebra remained stable.

The estimate was higher - at 2,812 - than the previous estimate in 2016. This increase in numbers is because GGR teams were able to more intensively cover some key areas which were not accessible in 2016, including Laisamis where our Grevy’s Zebra Warriors operate and El Barta where our Grevy’s Zebra Ambassadors operate. In these remote areas, although we know the Grevy’s zebra population is relatively healthy from our own monitoring, it has been difficult to get a reliable, scientific estimate, due to the large size of the area. Now, thanks to a collaborative effort of local and international partners, we can say with confidence that the investment in these programs has been absolutely worth it!

For the areas that were covered in both 2016 and 2018, there was no significant change in numbers, meaning that despite the drought and conflict of 2017, Grevy’s zebra remained stable. However, as expected, the proportion of foals and juveniles in the population dropped from 30% in 2016 to 22% in 2018, reflecting that conditions were not favourable for population growth. Overall, despite having our highest mortality in 2017, Grevy’s zebra held their own, which is very positive!

Including Ethiopia’s population, this takes the global estimate of Grevy’s zebra to just over 3,000. The information gained from the GGR is being used by GZT and our partners to inform and prioritise our conservation management actions. We are aiming to repeat the GGR biennually. Come and join us for GGR 2020!

by eyedesign, nairobi, kenya
Green Web Hosting! This site hosted by DreamHost.