Grevy's Zebra Anthrax
Grevy's zebra anthrax response from Marwell Wildlife
Threatened by competition with domestic livestock, habitat degradation and, in some areas, unsustainable hunting, Grevy’s zebra (Equus zebra) has suffered a rapid collapse in range and numbers.
From an estimated 15,000 in the late 1970s, there are now only between 1,700 and 2,100 animals left with many living in small, fragmented populations. The largest contiguous population occurs in the northern rangelands of Kenya.
In December 2005, an outbreak of anthrax was confirmed in this area, causing deaths in domestic livestock and wildlife alike, but disproportionately affecting equids. By the end of February 2006, it was estimated that over 100 Grevy’s zebras had died of anthrax. Left unchecked, this rate of mortality was predicted to result in catastrophic losses amongst this important population.
The plight of this important Grevy’s zebra population triggered an emergency response by local and international stakeholders. Following recommendations from wildlife and anthrax epidemiologists, an emergency vaccination of Grevy’s zebras was planned and donor funding sought.The safety and efficacy of the anthrax vaccine for Grevy’s zebras was tested under controlled conditions at the Lewa Wildlife Conservancy. With positive results, an operation to vaccinate the affected population was then undertaken.
The vaccine was successfully delivered by injection dart from the ground or by helicopter to 620 out of a population of approximately 1,000 Grevy’s zebras. All individuals treated were identified by age and sex class, and their unique stripe pattern for future monitoring. Grevy’s zebra mortality due to anthrax reduced post-vaccination, while the disease continued to affect plain’s zebra and livestock.
Monitoring efforts are ongoing and contingency plans in place to address any further outbreaks.
Developed by: Marwell Wildlife