Mysterious furthest game migration in Africa - News - Gondwana Collection

News

Gondwana's Newsroom

Mysterious furthest game migration in Africa

Avatar of inke inke - 06. November 2018 - Environment

Burchell's zebra on the Chobe floodplains on the Namibian side of the river. The range of hills in the background is in Botswana.

Dirk Heinrich

It is more than 500 kilometres for the round-trip from the Chobe floodplains in Namibia to Nxai Pan in the Nxai Pan National Park in Botswana. Thanks to satellite tracking devices this migration route of Burchell's zebra, popularly called plains zebra, has been known for several years now. Previously, researchers and conservationists always wondered where the zebra population of up to 3000 animals migrated to in the rainy season, when only a few Burchell's zebra remain on the shallow banks of the Chobe.

Shortly before the start of the rainy season in 2012 a total of eight Burchell's zebra mares were darted on the Namibian side of the Chobe in mid-September and on the river's bank in Botswana in mid-October and fitted with satellite transmitters. Researchers Piet Beytell and Pierre du Preez from Namibia's Ministry of Environment and Tourism worked on the project with researchers and wildlife experts from Botswana and the WWF (Robin Naidoo, Mike Chase, Kelly Landen, Greg Stuart-Hill and Russell Taylor). A few weeks later the animals with the satellite transmitters surprised the research group when their unexpected migration route was revealed: within seven to 19 days the mares together with their family group and other herds moved more than 250 kilometres south to Nxai Pan National Park in early December. One of the mares wearing a transmitter took 37 days with her group to reach the final destination, because that herd made a detour of a few weeks to the Seloko Plain.

When many zebra are in a small space together, quarrels between mares or rival stallions are the order of the day.

Apparently the first rains at Nxai Pan, 250 km south of the Chobe, were the starting signal for the migration to the south. More than 1,500 zebra were counted from the air during a game count at Nxai Pan on 21 February 2013. Just a few days before, conservationists and experts had estimated the zebra population at over 3000 animals. According to the GPS tracking devices the animals with transmitters stayed at Nxai Pan for between 53 and 96 days before moving north again. One of them died at the start of the migration to the north.

The northbound trek of the remaining zebra with transmitters and their family unit took its time and the distance covered was much larger than during the southbound migration. Since there seemed to be sufficient food and water on the way north, the return trip took 85 days on average and the distance travelled was between 735 and 1170 km on a zigzag course. Unfortunately, one transmitter failed after that, leaving only six zebra mares with a tracking device for the next migration. 

The zebra spend several weeks on the Chobe flood plains and repeatedly cross over from Namibia to Botswana and back through the river. Currently there are more than 3000 Burchell's zebra at the Chobe, as well as numerous other large mammal species. The two-year research revealed the longest migration route of large mammals known in Africa so far. The zebra of the Chobe migrate further than the zebra and wildebeest in East Africa. It remains a mystery why the striped odd-toed ungulates make the long round-trip of at least 500 km from the Chobe to Nxai Pan every year, when there is equally good grazing 60 km away on the Seloko Plain or 100 km away in the Savuti Marsh. 

Further research is needed, not only to learn more about this unique migration of Burchell's zebra, but also to find out whether other species travel that far together with the zebra. Mid-September just over 800 Zebras were counted on the floodplains east of Chobe River Camp on the Namibian side during a game census.

Burchell's zebra on one of the Chobe floodplains on the Namibian side.
New comment

0 comments

Stay up-to-date with our monthly 'Gondwana Tracks' Newsletter Sign up Today