Grevy’s zebra census
Grevy’s Zebra is the world’s rarest zebra and the most beautiful of them all. One can easily distinguish it by its black and white stripes. It once inhabited western Somalia, southern Ethiopia, and northern Kenya. But not anymore, at least for Somalia and Ethiopia. Today it almost exclusively inhabits only the northern part of Kenya. Sometimes you find them grazing side by side with the cattle. You can also see them with a herd of antelopes because they feel secure and protected in a group.
In the 1970s, there were around 15,000 of them in Kenya alone. But since then no one knew how many existed. Historically, they did the counting from the air. But it is hard to get the correct estimate of the population from aerial surveys. This is because zebras like to shade under trees to avoid the heat of the day. Hence, detecting and accurately counting them was always a challenge. It required a mass effort on the ground.
30th and 31st of January 2016 saw the carrying out of such a herculean initiative. For the first time Kenya undertook a citizen science-based census of Grevy’s zebras, a beautiful and endangered species of zebras found nowhere else in the world. The Great Grevy’s Rally was its name. The Laikipia Wildlife Forum and the Grevy’s Zebra Trust spearheaded it. Among many others, the main collaborators involved were Lewa, The Kenya Wildlife Service, Northern Rangelands Trust and community conservancies, Marwell Wildlife, county governments of Laikipia, Princeton University, and the Isiolo, Marsabit, and Meru counties.
Unusual census participants
For this momentous event, rangers, conservationists, government representatives, corporates and communities including citizen scientists came together to collect photographic data of Grevy’s zebras. A citizen scientist was anyone who conducts scientific research. 118 teams consisting of around 500 people in total participated in photographing these beautiful animals across the vast landscapes of Laikipia, Isiolo, Marsabit and Samburu counties. Driving through the dusty roads ranging 25,000 km2 on two successive days, they took around 40,000 images of geo-tagged Grevy’s zebras. For standardization, they chose the right-hand side of the zebras.
Princeton University contribution
The age-structured survey used advanced technology to gather critical demographic data. The Princeton University team checked the individual profiles for sexing and aging. The team at Princeton University then used its exclusive newly developed software to identify and match each based on ‘hotspots’ created from their unique stripe patterns. In this way, they were able to overcome the population census challenge yielding a more accurate estimate.
Accurate census results
On the 3rd of September 2016 at the Great Grevy’s Ball in Nanyuki the authorities released the results. It was a fun evening attended by Kitili Mbathi, Head of the Kenya Wildlife Service, county government representatives and the US Ambassador Robert Godec. With a margin of error of 93, the results suggest that there are approximately 2,350 of this rare species of zebras in Kenya. That is 90% of the world’s population of Grevy’s zebras.
In addition to the size, they also assessed the health of the populace by finding out their sex structure and age. By and large, the Grevy’s population is stable except in Meru due to a large number of predators especially the lion population in Lewa Wildlife Conservancy. The greatest proportion resides in Laikipia, an ecosystem in northern Kenya. Encouragingly, the populations in Samburu were shown to be growing too with Isiolo and Marsabit not far behind. It was the most precise estimate the Grevy’s has ever seen.
Grevy conservation efforts
The census followed a meeting of the participants including The Princeton University team, local ranchers, citizens, scientists, and conservationists. A discussion ensued about the human intervention needed to conserve the Grevy’s zebra. They also took the resident’s viewpoints into consideration. All of them are now using the data collected from the survey to shape conservation strategies and to prioritize future conservation actions.
The challenge now is to let the populations grow by ensuring the efficient management of optimal conditions that will allow for Grevy’s zebra population growth. For example, the most crucial here is the loss of habitat. Putting measures in place that would restore the grasslands in a way that would allow both the wild animals and the livestock to cohabit can mitigate that loss.
Droughts are rampant in the parks and conservancies of northern Kenya because rainfalls are unpredictable. During droughts, water is scarce. So, there is constant competition for the available water between the animals and livestock. Often droughts have been the reason for the hostility between the cattle herders and Rangers.
The stakeholders that attended the workshop strongly recommended wisely and sensitively managing access to water resources benefitting communities as well as wildlife. Financial resources were also pledged to reinvigorate degraded land. Additionally, devolution, the development of organizations and community conservancies, will help to facilitate rangeland recovery. Careful infrastructure planning is required to allow communities and wildlife to continue to live safely and sustainably. They also addressed the huge lion predation rates.
Grevy’s zebras crossing forward
The Grevy’s Zebra census conducted was one of its kind. It was a culmination of unique partnerships, all of them having a vested interest in protecting the magnificent and beautiful animal – Grevy’s zebra. And they graciously gave their time voluntarily. Participants demonstrated goodwill to diligently carry out the conservation action points discussed at the workshop.
The idea is to run three consecutive censuses with the intention of getting more people of the public at large and constituencies out there. Hopefully, they would be able to maintain the momentum and the motivation of this collaborative effort.