Last year, news from Botswana were saddening. 330 elephants had died in the Okavango Delta where several rivers form a very complex system of twisting channels and wetlands. This year, biologists determined that toxic algae in the river water, not gun-crazed tourists or poachers, had killed the animals. Good news from Botswana came with the announcement that the long-awaited Kazungula Bridge opened on May 10.