National Geographic : 1990 Dec
Botswana has set aside 17 percent of its land as nationalparks or game reserves, one of the highest percentages of any nation. However, measures taken to protect the cattle industry have sometimes proved disastrousfor wildlife. Beginning in the 1950s the government builtfences to control disease in com mercial herds, which today must comply with import standardsset by the European Community for disease-free beef. Some of thesefences restrict wildlife migration to andfrom tradi tionalwater sources. As a result many animals have died-more than 50,000 wildebeests in 1983 alone.