NewScientist (13 June 2015, paywall) reports on elephant migrations:
AFRICAN elephants are crossing borders to escape poaching. They seem to be heading to Botswana, Gabon, Namibia and Uganda. Political stability, relatively sparse populations and low levels of government corruption mean these countries are bucking the trend for declining elephant numbers.
Meanwhile, those countries with high levels of corruption are seeing their elephant populations drop. For example, Greater Elephant Census reports on Mozambique:
This preliminary data suggests alarming news; elephant populations appear to have plummeted in many traditional habitats including Niassa Reserve, Limpopo National Park, Quirimbas National Park, Tchuma Tchato and The Tete area. It appears from this preliminary data that in five years there has been a 48% decline in Mozambique due to severe poaching, with formerly elephant-rich ecosystems such as the Niassa Reserve experiencing losses of 63% in three years.
They comment positively on Uganda, negatively on Tanzania here and here. The Wildlife Conservation Society, which also supplies information on elephant populations, is here.