Home Magazine Issues Dec 2009-Jan 2010 Zebras – Main article Dec 2009-Jan 2010

Zebras

By Scott McMillan

Uganda is home to one of the most beautifully striped of beasts, the zebra. Lions love to hunt them and people love to see them. Whatever the case, no classic African safari experience is complete without having seen the black and white striped zebra galloping through the grasslands. Originally, Uganda had thousands of zebra roaming central and northern Uganda. But during the second half of the last century, more than 90% of them were killed by man. Uganda used to have the largest population of hoof stock species in all of Africa. Also, it is hypothesized that the Nile River made a natural barrier to most large mammal populations in the north and central parts of Uganda. This meant zebras living in central and southern Uganda originally came from Tanzania, while zebras in the north originally came from Kenya; with the possibility that they have never migrated across the Nile. Currently, there are only about 3,100 zebra left in Uganda- 3,000 of them living in Central Uganda in and around Lake Mburo; and just under a hundred living in the extreme north eastern corner of Uganda- in Kidepo Valley National Park. Zebras are on of the few larger mammals that use a pied, or black and white, pattern. Actually, zebras are mainly white with black stripes. Why zebras evolved repeating black and white stripes is often debated. It is thought that the pattern, when put together by several zebras forming a herd, distracts predators from picking out individual targets to focus their attack onto. There is no question that this pattern does, to some degree, perform that service. Often, when viewing a herd of zebras it becomes very difficult to count individuals. Another possibility for the pattern is that it is believed to somehow act as a cooling mechanism for the zebras. Zebras are in the family Equidae, or horse family. They further belong to the odd toed ungulates- having one main hoof on each leg that they use for support. They are a highly gregarious species that enjoy coming together in large groups for social interaction. However, they all belong to a smaller group, or harem. The harem consists of a stable population of females and their young, together with a stallion. In each harem there is a hierarchy of females- lead by an alpha female. This alpha female and the stallion share in responsibilities. The alpha female will dictate when and where the harem will move while the stallion mainly protects the harem from predators and other would be stallions. As the young reach sexual maturity, about one and a half years of age, the young females will go to another group to live out the remainder of there life; while the males will be kicked out into the bachelor group. Since not all the stallions in a zebra population can each have there own harem, the ones that do not have a harem of there own, form an amorphous group known as a bachelor herd. Here the single bachelors live together until they are able to get a harem of their own. Otherwise, they live out there entire life in the bachelor herd. The way a bachelor gets a harem is either by “stealing females from other harems or by simply taking over an entire harem. Either way, it usually involves fierce fighting between the bachelor and the stallion of a harem. It’s important for zebras to live in some type of group since it greatly increases their chance of overall survival. When zebras move from place to place, they walk in a line. In a harem, usually the alpha female will lead the group, followed by her offspring, then the stallion and then the lesser ranking females and their offspring. Zebras have a wide home range. They are found as far south as the tip of South Africa, as far east as the coast of Kenya, as far west as Namibia, and as far North as Southern Sudan. Zebras are a hardy animal and can live in a variety of habitat. However, they tend to prefer open grassland that allows for abundant grazing and the openness to watch out for predators. Zebras are known as “bulk grazers“- meaning they have the capacity to eat large amounts of low quality forage, through grazing (eating vegetation from the ground such as grasses and forbs). However, zebras are not above eating very succulent vegetation such as fresh grass, flowers, and even fruits and vegetables. The zebras in Kidepo are locally known as “mane-less zebras because the males drop their mane as they age. This population has ceased migrating and now spends the entire year in Kidepo valley. Years of living as an isolated population have caused them to look and behave differently to the zebras in Lake Mburo and it’s quite possible that this is a distinct subspecies of zebra. If so, it would be Uganda’s first sub specie of the Plains, or Burchell’s zebra. The future of zebras in Uganda is shaky in some parts. In Lake Mburo, zebras are in the thousands and are relatively stable. They even spend as much time on cattle ranches as in the park itself. However, the zebras in Kidepo suffer a different fate. They have gone from over 500 in the 1980’s to now less than 100 today. This has mainly been due to a history of poaching and climate change. In the 70’s and 80’s, poaching took its toll on many of the wildlife, certainly the zebras of Kidepo. In essence, a “fractured ecosystem was created from this poaching. Many of the animal species in Kidepo were wiped out entirely, such as the Northern white rhino, Roan antelope, and Grant’s gazelle; or fell to such low numbers as to almost be nonexistent, such as the greater kudu, eland, and giraffe. Then, by the mid 90’s, a significant change in climate occurred with the advent of “El Nino. El Nino caused more rain to fall than in the past; and as a result, caused Kidepo to switch from a dry semi arid grassland into a wetter savannah with taller grass. This taller grass has caused several species in Kidepo to struggle with hunting and being hunted. For prey, such as the zebras, it’s more difficult to see potential predators. These two factors have lead the predators of Kidepo to focus mainly on zebras and warthogs; thereby not giving zebras a chance to recuperate their numbers. Zebras still number around 1,000,000 worldwide and not on the CITES endangered list, yet. But the beginning of the end always starts somewhere; and often times slowly so that man isn’t interested or doesn’t notice. If nothing is done for the zebras of Kidepo, they could be a thing of the past in the next 12 years. Maintaining the biodiversity of an area is of key importance in today’s world. So, come to Kidepo or Lake Mburo and support the parks of Uganda. It’s an experience that you won’t forget. Eds Note: Scott has been doing research on zebras in Kidepo for the last three years. He is currently setting up the Kidepo Wildlife Foundation with the hope of maintaining the biodiversity of Kidepo and the surrounding region.

For more information, please contact:

Scott McMillan

Mobile: +256 777 671557

Email: elephant9669@hotmail.com

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